Implausible Time Records [Archive]

Tim Newport-Peace[_6_]

May 5th 19, 05:43 PM

At 16:26 05 May 2019, Dan Marotta wrote:
>Yes, it was from the vario which just started acting up.Â* The ClearNav
>II display's USB stick did not have the flight.Â* I may have neglected to

>download that.
>
>Lately I've been getting a boatload of GPS drop outs.Â* Maybe that's
>because I'm close to the source of the interference testing or maybe
>it's because I've cut my antennae cables to length in my cockpit.Â* I now

>seem to recall reading that one should not shorten the cables. I know
>about reflections due to wavelength/transmission line length, but I was
>unaware that that would affect reception.Â* Do I need to acquire new
>antennae?Â* The antenna that came with my PF portable was 10 meters
>long!Â* Who needs a big bundle of cable under the panel?
>
>On 5/5/2019 9:49 AM, JS wrote:
>> On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote:
>>> For my last three flights I've been getting a message from OLC warning
>>> of implausible time records in the igc file.Â* Does anyone know what
>this
>>> means and what I might do to correct the problem? I've asked the
>>> question on the ClearNav forum but haven't gotten a reply yet.
>>>
>>> Here's a link to the file if that helps:
>>>
https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
>>> --
>>> Dan, 5J
>> Noticed it was from the vario. I'll use a vario file today and see...
>> Jim
>
>--
>Dan, 5J
>
Looking at the file, there is an out-of-sequence issue:

Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC
---------------------------------------------------------------------
Out of Sequence Error -
B1903383458935N10559992WA0184701874001999104104113 000
B1903393458935N10600013WA0184901876001999112112116 000
B1903373458935N10600035WA0185101877001999115115119 000
B1903383458936N10600057WA0185301878001999119119122 000

Could this be the issue?

Dan Marotta

May 5th 19, 06:06 PM

I don't see what you're seeing.Â* But how could records be out of
sequence?Â* Maybe because my position apparently reversed while
thermalling during a GPS outage and getting one or two hits and then
another drop out, etc.?

On 5/5/2019 10:43 AM, Tim Newport-Peace wrote:
> At 16:26 05 May 2019, Dan Marotta wrote:
>> Yes, it was from the vario which just started acting up.Ã‚Â* The ClearNav
>> II display's USB stick did not have the flight.Ã‚Â* I may have neglected to
>> download that.
>>
>> Lately I've been getting a boatload of GPS drop outs.Ã‚Â* Maybe that's
>> because I'm close to the source of the interference testing or maybe
>> it's because I've cut my antennae cables to length in my cockpit.Ã‚Â* I now
>> seem to recall reading that one should not shorten the cables. I know
>> about reflections due to wavelength/transmission line length, but I was
>> unaware that that would affect reception.Ã‚Â* Do I need to acquire new
>> antennae?Ã‚Â* The antenna that came with my PF portable was 10 meters
>> long!Ã‚Â* Who needs a big bundle of cable under the panel?
>>
>> On 5/5/2019 9:49 AM, JS wrote:
>>> On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote:
>>>> For my last three flights I've been getting a message from OLC warning
>>>> of implausible time records in the igc file.Ã‚Â* Does anyone know what
>> this
>>>> means and what I might do to correct the problem? I've asked the
>>>> question on the ClearNav forum but haven't gotten a reply yet.
>>>>
>>>> Here's a link to the file if that helps:
>>>>
> https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
>>>> --
>>>> Dan, 5J
>>> Noticed it was from the vario. I'll use a vario file today and see...
>>> Jim
>> --
>> Dan, 5J
>>
> Looking at the file, there is an out-of-sequence issue:
>
> Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC
> ---------------------------------------------------------------------
> Out of Sequence Error -
> B1903383458935N10559992WA0184701874001999104104113 000
> B1903393458935N10600013WA0184901876001999112112116 000
> B1903373458935N10600035WA0185101877001999115115119 000
> B1903383458936N10600057WA0185301878001999119119122 000
>
> Could this be the issue?
>
>
>

--
Dan, 5J

Tim Newport-Peace[_6_]

May 5th 19, 08:05 PM

Dan,

Open your file with a text editor and search for "B190338"
This will put you in the right area.
In each record, after the letter B, the next six bytes are the time.

After B190339 the time jumps back to B190337, which is odd, and leads to
there being two records with a time of 190338, and also 190339.

Odd, but I have seen this before. Maybe you can avoid it in future by
setting a longer fix interval, even 2 seconds might help, but no promises.

I am not seeing any GPS outage around that time. This would be shown by the
Letter "A" in the 25th byte changing to a "V".

Although it does not help a lot, the sequence error seems to happen as you
left the ground, so I guess you were not reversing turns?

I'm not saying this is what OLC are complaining about, just that it is odd
and it might be.

Tim.
--

At 17:06 05 May 2019, Dan Marotta wrote:
>I don't see what you're seeing.Â* But how could records be out of
>sequence?Â* Maybe because my position apparently reversed while
>thermalling during a GPS outage and getting one or two hits and then
>another drop out, etc.?
>
>On 5/5/2019 10:43 AM, Tim Newport-Peace wrote:
>> At 16:26 05 May 2019, Dan Marotta wrote:
>>> Yes, it was from the vario which just started acting up.Ã‚Â* The
>ClearNav
>>> II display's USB stick did not have the flight.Ã‚Â* I may have
neglected
>to
>>> download that.
>>>
>>> Lately I've been getting a boatload of GPS drop outs.Ã‚Â* Maybe that's
>>> because I'm close to the source of the interference testing or maybe
>>> it's because I've cut my antennae cables to length in my cockpit.Ã‚Â*
I
>now
>>> seem to recall reading that one should not shorten the cables. I know
>>> about reflections due to wavelength/transmission line length, but I
was
>>> unaware that that would affect reception.Ã‚Â* Do I need to acquire new
>>> antennae?Ã‚Â* The antenna that came with my PF portable was 10 meters
>>> long!Ã‚Â* Who needs a big bundle of cable under the panel?
>>>
>>> On 5/5/2019 9:49 AM, JS wrote:
>>>> On Sunday, May 5, 2019 at 8:38:57 AM UTC-7, Dan Marotta wrote:
>>>>> For my last three flights I've been getting a message from OLC
warning
>>>>> of implausible time records in the igc file.Ã‚Â* Does anyone know
what
>>> this
>>>>> means and what I might do to correct the problem? I've asked the
>>>>> question on the ClearNav forum but haven't gotten a reply yet.
>>>>>
>>>>> Here's a link to the file if that helps:
>>>>>
>>
https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
>>>>> --
>>>>> Dan, 5J
>>>> Noticed it was from the vario. I'll use a vario file today and see...
>>>> Jim
>>> --
>>> Dan, 5J
>>>
>> Looking at the file, there is an out-of-sequence issue:
>>
>> Checking File C:\Users\Public\Documents\GPS\2019-05-04-CNI-V8Q-01.IGC
>> ---------------------------------------------------------------------
>> Out of Sequence Error -
>> B1903383458935N10559992WA0184701874001999104104113 000
>> B1903393458935N10600013WA0184901876001999112112116 000
>> B1903373458935N10600035WA0185101877001999115115119 000
>> B1903383458936N10600057WA0185301878001999119119122 000
>>
>> Could this be the issue?
>>
>>
>>
>
>--
>Dan, 5J
>

Dan Marotta

May 5th 19, 11:43 PM

Thanks Tim

I'll increase my time interval to 2 seconds and see if that helps.

Strange that the igc file does not show GPS drop outs since my ClearNav
screen went white with the caption (something like) No GPS.Â* Zero
satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
PowerFlarm portable screen also went blank with a "Zero satellites" message.

On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
> Dan,
>
> Open your file with a text editor and search for "B190338"
> This will put you in the right area.
> In each record, after the letter B, the next six bytes are the time.
>
> After B190339 the time jumps back to B190337, which is odd, and leads to
> there being two records with a time of 190338, and also 190339.
>
> Odd, but I have seen this before. Maybe you can avoid it in future by
> setting a longer fix interval, even 2 seconds might help, but no promises.
>
> I am not seeing any GPS outage around that time. This would be shown by the
> Letter "A" in the 25th byte changing to a "V".
>
> Although it does not help a lot, the sequence error seems to happen as you
> left the ground, so I guess you were not reversing turns?
>
> I'm not saying this is what OLC are complaining about, just that it is odd
> and it might be.
>
> Tim.

--
Dan, 5J

JS[_5_]

May 6th 19, 02:42 AM

On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
> Thanks Tim
>
> I'll increase my time interval to 2 seconds and see if that helps.
>
> Strange that the igc file does not show GPS drop outs since my ClearNav
> screen went white with the caption (something like) No GPS.Â* Zero
> satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
> PowerFlarm portable screen also went blank with a "Zero satellites" message.
>
> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
> > Dan,
> >
> > Open your file with a text editor and search for "B190338"
> > This will put you in the right area.
> > In each record, after the letter B, the next six bytes are the time.
> >
> > After B190339 the time jumps back to B190337, which is odd, and leads to
> > there being two records with a time of 190338, and also 190339.
> >
> > Odd, but I have seen this before. Maybe you can avoid it in future by
> > setting a longer fix interval, even 2 seconds might help, but no promises.
> >
> > I am not seeing any GPS outage around that time. This would be shown by the
> > Letter "A" in the 25th byte changing to a "V".
> >
> > Although it does not help a lot, the sequence error seems to happen as you
> > left the ground, so I guess you were not reversing turns?
> >
> > I'm not saying this is what OLC are complaining about, just that it is odd
> > and it might be.
> >
> > Tim.
>
> --
> Dan, 5J

That smells of GPS jamming.
Check this page.
https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
I did not have a problem with the vario file today. My antenna has a shortened cable to a MECA divider, then a short SMA-SMA link cable.
Jim

Dan Marotta

May 6th 19, 04:08 PM

Yes, the GPS jamming usually centers around Alamogordo and ranges out to
about 400 nm.Â* Moriarty is well within that area.Â* I've asked other
local pilots and they don't report so many drop outs.

Maybe there are just too many GPS antennae in my ship.Â* I'll take a look
at a divider for everything except the ADS-B WAAS GPS.Â* Its antenna is
mounted aft of the engine in the Stemme.Â* The rest are on or under the
glare shield.

On 5/5/2019 7:42 PM, JS wrote:
> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>> Thanks Tim
>>
>> I'll increase my time interval to 2 seconds and see if that helps.
>>
>> Strange that the igc file does not show GPS drop outs since my ClearNav
>> screen went white with the caption (something like) No GPS.Â* Zero
>> satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
>> PowerFlarm portable screen also went blank with a "Zero satellites" message.
>>
>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>> Dan,
>>>
>>> Open your file with a text editor and search for "B190338"
>>> This will put you in the right area.
>>> In each record, after the letter B, the next six bytes are the time.
>>>
>>> After B190339 the time jumps back to B190337, which is odd, and leads to
>>> there being two records with a time of 190338, and also 190339.
>>>
>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>> setting a longer fix interval, even 2 seconds might help, but no promises.
>>>
>>> I am not seeing any GPS outage around that time. This would be shown by the
>>> Letter "A" in the 25th byte changing to a "V".
>>>
>>> Although it does not help a lot, the sequence error seems to happen as you
>>> left the ground, so I guess you were not reversing turns?
>>>
>>> I'm not saying this is what OLC are complaining about, just that it is odd
>>> and it might be.
>>>
>>> Tim.
>> --
>> Dan, 5J
> That smells of GPS jamming.
> Check this page.
> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
> I did not have a problem with the vario file today. My antenna has a shortened cable to a MECA divider, then a short SMA-SMA link cable.
> Jim

--
Dan, 5J

kinsell

May 6th 19, 04:44 PM

Jamming is directed skyward, they're not taking out car gps's in a 400
nm radius. If you're getting bad time stamps just at liftoff, it's not
likely caused by jamming.

I'm suspicious of your cut-down gps cables, those are tiny wires to be
working on.

On 5/6/19 9:08 AM, Dan Marotta wrote:
> Yes, the GPS jamming usually centers around Alamogordo and ranges out to
> about 400 nm.Â* Moriarty is well within that area.Â* I've asked other
> local pilots and they don't report so many drop outs.
>
> Maybe there are just too many GPS antennae in my ship.Â* I'll take a look
> at a divider for everything except the ADS-B WAAS GPS.Â* Its antenna is
> mounted aft of the engine in the Stemme.Â* The rest are on or under the
> glare shield.
>
> On 5/5/2019 7:42 PM, JS wrote:
>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>> Thanks Tim
>>>
>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>
>>> Strange that the igc file does not show GPS drop outs since my ClearNav
>>> screen went white with the caption (something like) No GPS.Â* Zero
>>> satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>>> message.
>>>
>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>> Dan,
>>>>
>>>> Open your file with a text editor and search for "B190338"
>>>> This will put you in the right area.
>>>> In each record, after the letter B, the next six bytes are the time.
>>>>
>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>> leads to
>>>> there being two records with a time of 190338, and also 190339.
>>>>
>>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>> promises.
>>>>
>>>> I am not seeing any GPS outage around that time. This would be shown
>>>> by the
>>>> Letter "A" in the 25th byte changing to a "V".
>>>>
>>>> Although it does not help a lot, the sequence error seems to happen
>>>> as you
>>>> left the ground, so I guess you were not reversing turns?
>>>>
>>>> I'm not saying this is what OLC are complaining about, just that it
>>>> is odd
>>>> and it might be.
>>>>
>>>> Tim.
>>> --
>>> Dan, 5J
>> That smells of GPS jamming.
>> Check this page.
>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>> I did not have a problem with the vario file today. My antenna has a
>> shortened cable to a MECA divider, then a short SMA-SMA link cable.
>> Jim
>

Tim Newport-Peace[_6_]

May 6th 19, 05:04 PM

Not necessarily related, but I noticed that your Firmware is dated
10-Feb-2017. I feel sure that there have been updates since then.

At 15:08 06 May 2019, Dan Marotta wrote:
>Yes, the GPS jamming usually centers around Alamogordo and ranges out to
>about 400 nm.Â* Moriarty is well within that area.Â* I've asked other
>local pilots and they don't report so many drop outs.
>
>Maybe there are just too many GPS antennae in my ship.Â* I'll take a look

>at a divider for everything except the ADS-B WAAS GPS.Â* Its antenna is
>mounted aft of the engine in the Stemme.Â* The rest are on or under the
>glare shield.
>
>On 5/5/2019 7:42 PM, JS wrote:
>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>> Thanks Tim
>>>
>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>
>>> Strange that the igc file does not show GPS drop outs since my
ClearNav
>>> screen went white with the caption (something like) No GPS.Â* Zero
>>> satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>message.
>>>
>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>> Dan,
>>>>
>>>> Open your file with a text editor and search for "B190338"
>>>> This will put you in the right area.
>>>> In each record, after the letter B, the next six bytes are the time.
>>>>
>>>> After B190339 the time jumps back to B190337, which is odd, and
leads
>to
>>>> there being two records with a time of 190338, and also 190339.
>>>>
>>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>>> setting a longer fix interval, even 2 seconds might help, but no
>promises.
>>>>
>>>> I am not seeing any GPS outage around that time. This would be shown
by
>the
>>>> Letter "A" in the 25th byte changing to a "V".
>>>>
>>>> Although it does not help a lot, the sequence error seems to happen
as
>you
>>>> left the ground, so I guess you were not reversing turns?
>>>>
>>>> I'm not saying this is what OLC are complaining about, just that it
is
>odd
>>>> and it might be.
>>>>
>>>> Tim.
>>> --
>>> Dan, 5J
>> That smells of GPS jamming.
>> Check this page.
>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>> I did not have a problem with the vario file today. My antenna has a
>shortened cable to a MECA divider, then a short SMA-SMA link cable.
>> Jim
>
>--
>Dan, 5J
>

Tim Newport-Peace[_6_]

May 6th 19, 05:07 PM

GPS signals are line-of-sight only, and as the problem ocurred at take-off,
the source would have to be very close, like visible.

At 15:44 06 May 2019, kinsell wrote:
>Jamming is directed skyward, they're not taking out car gps's in a 400
>nm radius. If you're getting bad time stamps just at liftoff, it's not
>likely caused by jamming.
>
>I'm suspicious of your cut-down gps cables, those are tiny wires to be
>working on.
>
>
>
>On 5/6/19 9:08 AM, Dan Marotta wrote:
>> Yes, the GPS jamming usually centers around Alamogordo and ranges out to

>> about 400 nm.Â* Moriarty is well within that area.Â* I've asked other
>> local pilots and they don't report so many drop outs.
>>
>> Maybe there are just too many GPS antennae in my ship.Â* I'll take a
look
>
>> at a divider for everything except the ADS-B WAAS GPS.Â* Its antenna is

>> mounted aft of the engine in the Stemme.Â* The rest are on or under the

>> glare shield.
>>
>> On 5/5/2019 7:42 PM, JS wrote:
>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>> Thanks Tim
>>>>
>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>
>>>> Strange that the igc file does not show GPS drop outs since my
ClearNav
>>>> screen went white with the caption (something like) No GPS.Â* Zero
>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS".Â* The
>>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>>>> message.
>>>>
>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>> Dan,
>>>>>
>>>>> Open your file with a text editor and search for "B190338"
>>>>> This will put you in the right area.
>>>>> In each record, after the letter B, the next six bytes are the time.
>>>>>
>>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>>> leads to
>>>>> there being two records with a time of 190338, and also 190339.
>>>>>
>>>>> Odd, but I have seen this before. Maybe you can avoid it in future
by
>>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>>> promises.
>>>>>
>>>>> I am not seeing any GPS outage around that time. This would be shown

>>>>> by the
>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>
>>>>> Although it does not help a lot, the sequence error seems to happen
>>>>> as you
>>>>> left the ground, so I guess you were not reversing turns?
>>>>>
>>>>> I'm not saying this is what OLC are complaining about, just that it
>>>>> is odd
>>>>> and it might be.
>>>>>
>>>>> Tim.
>>>> --
>>>> Dan, 5J
>>> That smells of GPS jamming.
>>> Check this page.
>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>> I did not have a problem with the vario file today. My antenna has a
>>> shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>> Jim
>>
>
>

Dan Marotta

May 6th 19, 05:32 PM

I've also had drop outs with my Trig TN-70 and its antenna, though not
as often as with my soaring GPSs.

Yes, the wires are tiny, but it was pretty simple to desolder them from
the puck, clip the cable to length, strip, tin, and solder.Â* I did that
for 3 antennae and they generally work fine, but lately have acting up.

I'm looking at THESE
<https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
as replacements.Â* Any comments?Â* I wonder if that IPEX connector is a
push fit on the built in SMA connectors on the devices.Â* I'm also
considering replacing the modified antennae with factory new units and
using the longer cables to mount them on opposite canopy rails in the
Stemme.Â* Those should be about a meter apart.

On 5/6/2019 9:44 AM, kinsell wrote:
> Jamming is directed skyward, they're not taking out car gps's in a 400
> nm radius.Â* If you're getting bad time stamps just at liftoff,Â* it's
> not likely caused by jamming.
>
> I'm suspicious of your cut-down gps cables, those are tiny wires to be
> working on.
>
>
>
> On 5/6/19 9:08 AM, Dan Marotta wrote:
>> Yes, the GPS jamming usually centers around Alamogordo and ranges out
>> to about 400 nm.Â* Moriarty is well within that area.Â* I've asked
>> other local pilots and they don't report so many drop outs.
>>
>> Maybe there are just too many GPS antennae in my ship.Â* I'll take a
>> look at a divider for everything except the ADS-B WAAS GPS.Â* Its
>> antenna is mounted aft of the engine in the Stemme. The rest are on
>> or under the glare shield.
>>
>> On 5/5/2019 7:42 PM, JS wrote:
>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>> Thanks Tim
>>>>
>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>
>>>> Strange that the igc file does not show GPS drop outs since my
>>>> ClearNav
>>>> screen went white with the caption (something like) No GPS. Zero
>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>>>> message.
>>>>
>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>> Dan,
>>>>>
>>>>> Open your file with a text editor and search for "B190338"
>>>>> This will put you in the right area.
>>>>> In each record, after the letter B, the next six bytes are the time.
>>>>>
>>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>>> leads to
>>>>> there being two records with a time of 190338, and also 190339.
>>>>>
>>>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>>> promises.
>>>>>
>>>>> I am not seeing any GPS outage around that time. This would be
>>>>> shown by the
>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>
>>>>> Although it does not help a lot, the sequence error seems to
>>>>> happen as you
>>>>> left the ground, so I guess you were not reversing turns?
>>>>>
>>>>> I'm not saying this is what OLC are complaining about, just that
>>>>> it is odd
>>>>> and it might be.
>>>>>
>>>>> Tim.
>>>> --
>>>> Dan, 5J
>>> That smells of GPS jamming.
>>> Check this page.
>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>> I did not have a problem with the vario file today. My antenna has a
>>> shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>> Jim
>>
>

--
Dan, 5J

Dan Marotta

May 6th 19, 05:34 PM

You're correct, Tim.Â* I just checked and the latest firmware for the
vario is dated 5/10/18.Â* I'll download that today.Â* Still, I'm getting
the same error message from OLC for the ClearNav II computer with the
latest firmware installed.

On 5/6/2019 10:04 AM, Tim Newport-Peace wrote:
> Not necessarily related, but I noticed that your Firmware is dated
> 10-Feb-2017. I feel sure that there have been updates since then.
>
> At 15:08 06 May 2019, Dan Marotta wrote:
>> Yes, the GPS jamming usually centers around Alamogordo and ranges out to
>> about 400 nm.Ã‚Â* Moriarty is well within that area.Ã‚Â* I've asked other
>> local pilots and they don't report so many drop outs.
>>
>> Maybe there are just too many GPS antennae in my ship.Ã‚Â* I'll take a look
>> at a divider for everything except the ADS-B WAAS GPS.Ã‚Â* Its antenna is
>> mounted aft of the engine in the Stemme.Ã‚Â* The rest are on or under the
>> glare shield.
>>
>> On 5/5/2019 7:42 PM, JS wrote:
>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>> Thanks Tim
>>>>
>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>
>>>> Strange that the igc file does not show GPS drop outs since my
> ClearNav
>>>> screen went white with the caption (something like) No GPS.Ã‚Â* Zero
>>>> satellites.Ã‚Â* And the ClearNav vario said, "Warning no GPS".Ã‚Â* The
>>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>> message.
>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>> Dan,
>>>>>
>>>>> Open your file with a text editor and search for "B190338"
>>>>> This will put you in the right area.
>>>>> In each record, after the letter B, the next six bytes are the time.
>>>>>
>>>>> After B190339 the time jumps back to B190337, which is odd, and
> leads
>> to
>>>>> there being two records with a time of 190338, and also 190339.
>>>>>
>>>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>>>> setting a longer fix interval, even 2 seconds might help, but no
>> promises.
>>>>> I am not seeing any GPS outage around that time. This would be shown
> by
>> the
>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>
>>>>> Although it does not help a lot, the sequence error seems to happen
> as
>> you
>>>>> left the ground, so I guess you were not reversing turns?
>>>>>
>>>>> I'm not saying this is what OLC are complaining about, just that it
> is
>> odd
>>>>> and it might be.
>>>>>
>>>>> Tim.
>>>> --
>>>> Dan, 5J
>>> That smells of GPS jamming.
>>> Check this page.
>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>> I did not have a problem with the vario file today. My antenna has a
>> shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>> Jim
>> --
>> Dan, 5J
>>

--
Dan, 5J

kinsell

May 6th 19, 06:39 PM

On 5/6/19 10:32 AM, Dan Marotta wrote:
> I've also had drop outs with my Trig TN-70 and its antenna, though not
> as often as with my soaring GPSs.

Do they correlate with the engine running? If so, might be ignition noise.

>
> Yes, the wires are tiny, but it was pretty simple to desolder them from
> the puck, clip the cable to length, strip, tin, and solder.Â* I did that
> for 3 antennae and they generally work fine, but lately have acting up.

It's easy to overheat the dielectric in the coax, causing loss of signal
strength.

>
> I'm looking at THESE
> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is a
> push fit on the built in SMA connectors on the devices.Â* I'm also
> considering replacing the modified antennae with factory new units and
> using the longer cables to mount them on opposite canopy rails in the
> Stemme.Â* Those should be about a meter apart.
>
> On 5/6/2019 9:44 AM, kinsell wrote:
>> Jamming is directed skyward, they're not taking out car gps's in a 400
>> nm radius.Â* If you're getting bad time stamps just at liftoff,Â* it's
>> not likely caused by jamming.
>>
>> I'm suspicious of your cut-down gps cables, those are tiny wires to be
>> working on.
>>
>>
>>
>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>> Yes, the GPS jamming usually centers around Alamogordo and ranges out
>>> to about 400 nm.Â* Moriarty is well within that area.Â* I've asked
>>> other local pilots and they don't report so many drop outs.
>>>
>>> Maybe there are just too many GPS antennae in my ship.Â* I'll take a
>>> look at a divider for everything except the ADS-B WAAS GPS.Â* Its
>>> antenna is mounted aft of the engine in the Stemme. The rest are on
>>> or under the glare shield.
>>>
>>> On 5/5/2019 7:42 PM, JS wrote:
>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>> Thanks Tim
>>>>>
>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>
>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>> ClearNav
>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>> PowerFlarm portable screen also went blank with a "Zero satellites"
>>>>> message.
>>>>>
>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>> Dan,
>>>>>>
>>>>>> Open your file with a text editor and search for "B190338"
>>>>>> This will put you in the right area.
>>>>>> In each record, after the letter B, the next six bytes are the time.
>>>>>>
>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>>>> leads to
>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>
>>>>>> Odd, but I have seen this before. Maybe you can avoid it in future by
>>>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>>>> promises.
>>>>>>
>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>> shown by the
>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>
>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>> happen as you
>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>
>>>>>> I'm not saying this is what OLC are complaining about, just that
>>>>>> it is odd
>>>>>> and it might be.
>>>>>>
>>>>>> Tim.
>>>>> --
>>>>> Dan, 5J
>>>> That smells of GPS jamming.
>>>> Check this page.
>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>> I did not have a problem with the vario file today. My antenna has a
>>>> shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>>> Jim
>>>
>>
>
> --
> Dan, 5J

Dan Marotta

May 6th 19, 11:20 PM

These dropouts never occur during engine run which normally only runs 10
minutes or less from engine start to shutdown after takeoff.

Heating up the dielectric is something I didn't consider.Â* Maybe I
should replace the antennae...

On 5/6/2019 11:39 AM, kinsell wrote:
> On 5/6/19 10:32 AM, Dan Marotta wrote:
>> I've also had drop outs with my Trig TN-70 and its antenna, though
>> not as often as with my soaring GPSs.
>
> Do they correlate with the engine running?Â* If so, might be ignition
> noise.
>
>
>>
>> Yes, the wires are tiny, but it was pretty simple to desolder them
>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>> did that for 3 antennae and they generally work fine, but lately have
>> acting up.
>
> It's easy to overheat the dielectric in the coax, causing loss of
> signal strength.
>
>
>>
>> I'm looking at THESE
>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is a
>> push fit on the built in SMA connectors on the devices. I'm also
>> considering replacing the modified antennae with factory new units
>> and using the longer cables to mount them on opposite canopy rails in
>> the Stemme.Â* Those should be about a meter apart.
>>
>> On 5/6/2019 9:44 AM, kinsell wrote:
>>> Jamming is directed skyward, they're not taking out car gps's in a
>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,Â*
>>> it's not likely caused by jamming.
>>>
>>> I'm suspicious of your cut-down gps cables, those are tiny wires to
>>> be working on.
>>>
>>>
>>>
>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
>>>> asked other local pilots and they don't report so many drop outs.
>>>>
>>>> Maybe there are just too many GPS antennae in my ship.Â* I'll take a
>>>> look at a divider for everything except the ADS-B WAAS GPS.Â* Its
>>>> antenna is mounted aft of the engine in the Stemme. The rest are on
>>>> or under the glare shield.
>>>>
>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>> Thanks Tim
>>>>>>
>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>
>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>> ClearNav
>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>> satellites" message.
>>>>>>
>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>> Dan,
>>>>>>>
>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>> This will put you in the right area.
>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>> time.
>>>>>>>
>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>>>>> leads to
>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>
>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>> future by
>>>>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>>>>> promises.
>>>>>>>
>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>> shown by the
>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>
>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>> happen as you
>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>
>>>>>>> I'm not saying this is what OLC are complaining about, just that
>>>>>>> it is odd
>>>>>>> and it might be.
>>>>>>>
>>>>>>> Tim.
>>>>>> --
>>>>>> Dan, 5J
>>>>> That smells of GPS jamming.
>>>>> Check this page.
>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>> I did not have a problem with the vario file today. My antenna has
>>>>> a shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>>>> Jim
>>>>
>>>
>>
>> --
>> Dan, 5J
>

--
Dan, 5J

Tim Newport-Peace[_6_]

May 7th 19, 09:21 AM

Returning to the original problem, the warning from OLC is not particularly
helpful. The only problem detected was the out-of-sequence times. If these
were caused by corruption of the GPS signal, it should not affect the time
record. A failure of GPS signal will be shown in the IGC file as a zero GPS
altitude. This is not the case, therefore we can take it that it is not a
GPS problem.

As the time error occurred during take-off, when the glider was only a few
feet AGL, it was long before the start of the â€˜Soaring Performanceâ€™, so
OLC is being a bit pedantic. I very much doubt if a Badge Claim would have
noticed this. SeeYou just skips over it.

I see this as a problem owned by ClearNav, although I have seen similar
time sequence errors in other recorders over the years. It will be
interesting to see if it reappears with the latest firmware.

Tim.
--
At 22:20 06 May 2019, Dan Marotta wrote:
>These dropouts never occur during engine run which normally only runs 10
>minutes or less from engine start to shutdown after takeoff.
>
>Heating up the dielectric is something I didn't consider.Â* Maybe I
>should replace the antennae...
>
>On 5/6/2019 11:39 AM, kinsell wrote:
>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>> not as often as with my soaring GPSs.
>>
>> Do they correlate with the engine running?Â* If so, might be ignition
>> noise.
>>
>>
>>>
>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>> did that for 3 antennae and they generally work fine, but lately have
>>> acting up.
>>
>> It's easy to overheat the dielectric in the coax, causing loss of
>> signal strength.
>>
>>

>>>
>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,Â*

>>>> it's not likely caused by jamming.
>>>>
>>>> I'm suspicious of your cut-down gps cables, those are tiny wires to
>>>> be working on.
>>>>
>>>>

kinsell

May 7th 19, 03:21 PM

Looking at your flight logs on OLC, you have the last two that didn't
validate, but others earlier this year that did.

However, most of the altitude graphs are plotted with many hours of dead
time, with the flight being compressed into the very right hand part of
the graph. A very bizarre presentation.

Perhaps your ClearNav has a hardware fault that is gradually getting worse?

On 5/6/19 4:20 PM, Dan Marotta wrote:
> These dropouts never occur during engine run which normally only runs 10
> minutes or less from engine start to shutdown after takeoff.
>
> Heating up the dielectric is something I didn't consider.Â* Maybe I
> should replace the antennae...
>
> On 5/6/2019 11:39 AM, kinsell wrote:
>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>> not as often as with my soaring GPSs.
>>
>> Do they correlate with the engine running?Â* If so, might be ignition
>> noise.
>>
>>
>>>
>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>> did that for 3 antennae and they generally work fine, but lately have
>>> acting up.
>>
>> It's easy to overheat the dielectric in the coax, causing loss of
>> signal strength.
>>
>>
>>>
>>> I'm looking at THESE
>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is a
>>> push fit on the built in SMA connectors on the devices. I'm also
>>> considering replacing the modified antennae with factory new units
>>> and using the longer cables to mount them on opposite canopy rails in
>>> the Stemme.Â* Those should be about a meter apart.
>>>
>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,
>>>> it's not likely caused by jamming.
>>>>
>>>> I'm suspicious of your cut-down gps cables, those are tiny wires to
>>>> be working on.
>>>>
>>>>
>>>>
>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
>>>>> asked other local pilots and they don't report so many drop outs.
>>>>>
>>>>> Maybe there are just too many GPS antennae in my ship.Â* I'll take a
>>>>> look at a divider for everything except the ADS-B WAAS GPS.Â* Its
>>>>> antenna is mounted aft of the engine in the Stemme. The rest are on
>>>>> or under the glare shield.
>>>>>
>>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>>> Thanks Tim
>>>>>>>
>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>>
>>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>>> ClearNav
>>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>>> satellites" message.
>>>>>>>
>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>>> Dan,
>>>>>>>>
>>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>>> This will put you in the right area.
>>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>>> time.
>>>>>>>>
>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd, and
>>>>>>>> leads to
>>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>>
>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>>> future by
>>>>>>>> setting a longer fix interval, even 2 seconds might help, but no
>>>>>>>> promises.
>>>>>>>>
>>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>>> shown by the
>>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>>
>>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>>> happen as you
>>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>>
>>>>>>>> I'm not saying this is what OLC are complaining about, just that
>>>>>>>> it is odd
>>>>>>>> and it might be.
>>>>>>>>
>>>>>>>> Tim.
>>>>>>> --
>>>>>>> Dan, 5J
>>>>>> That smells of GPS jamming.
>>>>>> Check this page.
>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>>> I did not have a problem with the vario file today. My antenna has
>>>>>> a shortened cable to a MECA divider, then a short SMA-SMA link cable.
>>>>>> Jim
>>>>>
>>>>
>>>
>>> --
>>> Dan, 5J
>>
>

Dan Marotta

May 7th 19, 04:07 PM

Another thought:Â* Richard Kellerman advised me to snug the connectors
with a wrench.Â* Mine are probably only hand tight. Another small task...

On 5/6/2019 4:20 PM, Dan Marotta wrote:
> These dropouts never occur during engine run which normally only runs
> 10 minutes or less from engine start to shutdown after takeoff.
>
> Heating up the dielectric is something I didn't consider.Â* Maybe I
> should replace the antennae...
>
> On 5/6/2019 11:39 AM, kinsell wrote:
>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>> not as often as with my soaring GPSs.
>>
>> Do they correlate with the engine running?Â* If so, might be ignition
>> noise.
>>
>>
>>>
>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>> did that for 3 antennae and they generally work fine, but lately
>>> have acting up.
>>
>> It's easy to overheat the dielectric in the coax, causing loss of
>> signal strength.
>>
>>
>>>
>>> I'm looking at THESE
>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is
>>> a push fit on the built in SMA connectors on the devices. I'm also
>>> considering replacing the modified antennae with factory new units
>>> and using the longer cables to mount them on opposite canopy rails
>>> in the Stemme.Â* Those should be about a meter apart.
>>>
>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,Â*
>>>> it's not likely caused by jamming.
>>>>
>>>> I'm suspicious of your cut-down gps cables, those are tiny wires to
>>>> be working on.
>>>>
>>>>
>>>>
>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>>> out to about 400 nm. Moriarty is well within that area.Â* I've
>>>>> asked other local pilots and they don't report so many drop outs.
>>>>>
>>>>> Maybe there are just too many GPS antennae in my ship. I'll take a
>>>>> look at a divider for everything except the ADS-B WAAS GPS.Â* Its
>>>>> antenna is mounted aft of the engine in the Stemme. The rest are
>>>>> on or under the glare shield.
>>>>>
>>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>>> Thanks Tim
>>>>>>>
>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>>
>>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>>> ClearNav
>>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>>> satellites" message.
>>>>>>>
>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>>> Dan,
>>>>>>>>
>>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>>> This will put you in the right area.
>>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>>> time.
>>>>>>>>
>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd,
>>>>>>>> and leads to
>>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>>
>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>>> future by
>>>>>>>> setting a longer fix interval, even 2 seconds might help, but
>>>>>>>> no promises.
>>>>>>>>
>>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>>> shown by the
>>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>>
>>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>>> happen as you
>>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>>
>>>>>>>> I'm not saying this is what OLC are complaining about, just
>>>>>>>> that it is odd
>>>>>>>> and it might be.
>>>>>>>>
>>>>>>>> Tim.
>>>>>>> --
>>>>>>> Dan, 5J
>>>>>> That smells of GPS jamming.
>>>>>> Check this page.
>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>>> I did not have a problem with the vario file today. My antenna
>>>>>> has a shortened cable to a MECA divider, then a short SMA-SMA
>>>>>> link cable.
>>>>>> Jim
>>>>>
>>>>
>>>
>>> --
>>> Dan, 5J
>>
>

--
Dan, 5J

Dan Marotta

May 7th 19, 04:13 PM

No help from ClearNav (yet).Â* I've updated the CNvXC firmware but not
flown with it yet.Â* It's overcast here...Â* As stated elsewhere, I'll
snug the connectors with a wrench (spanner), and I've relocated the
antenna pucks further apart, though a local pilot tells me he has four
antennae lined up next to each other and has no problems with reception.

Elsewhere I said that I don't have drop outs with the engine running.Â*
That was not entirely true.Â* I've had drop outs during repositioning
flights over the Rocky Mountains at 18,000' MSL.Â* It's very annoying but
I can see where I'm going and I'm not scoring those flights.

If I lose any more flights, I'll have to buy new antennae...

On 5/7/2019 2:21 AM, Tim Newport-Peace wrote:
> Returning to the original problem, the warning from OLC is not particularly
> helpful. The only problem detected was the out-of-sequence times. If these
> were caused by corruption of the GPS signal, it should not affect the time
> record. A failure of GPS signal will be shown in the IGC file as a zero GPS
> altitude. This is not the case, therefore we can take it that it is not a
> GPS problem.
>
> As the time error occurred during take-off, when the glider was only a few
> feet AGL, it was long before the start of the Ã¢â‚¬ËœSoaring PerformanceÃ¢â‚¬â„¢, so
> OLC is being a bit pedantic. I very much doubt if a Badge Claim would have
> noticed this. SeeYou just skips over it.
>
> I see this as a problem owned by ClearNav, although I have seen similar
> time sequence errors in other recorders over the years. It will be
> interesting to see if it reappears with the latest firmware.
>
> Tim.

--
Dan, 5J

Dan Marotta

May 7th 19, 04:21 PM

An interesting thought, but I see the same whether I'm using the
ClearNav or the ClearNav vario.Â* I doubt both could be experiencing the
same fault at the same time.Â* It's really odd about the apparent time
compression on the OLC display.Â* My flights score and appear just fine
on skylines.aero.

On 5/7/2019 8:21 AM, kinsell wrote:
> Looking at your flight logs on OLC, you have the last two that didn't
> validate, but others earlier this year that did.
>
> However, most of the altitude graphs are plotted with many hours of
> dead time, with the flight being compressed into the very right hand
> part of the graph. A very bizarre presentation.
>
> Perhaps your ClearNav has a hardware fault that is gradually getting
> worse?
>
>
>
> On 5/6/19 4:20 PM, Dan Marotta wrote:
>> These dropouts never occur during engine run which normally only runs
>> 10 minutes or less from engine start to shutdown after takeoff.
>>
>> Heating up the dielectric is something I didn't consider.Â* Maybe I
>> should replace the antennae...
>>
>> On 5/6/2019 11:39 AM, kinsell wrote:
>>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>>> not as often as with my soaring GPSs.
>>>
>>> Do they correlate with the engine running?Â* If so, might be ignition
>>> noise.
>>>
>>>
>>>>
>>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>>> did that for 3 antennae and they generally work fine, but lately
>>>> have acting up.
>>>
>>> It's easy to overheat the dielectric in the coax, causing loss of
>>> signal strength.
>>>
>>>
>>>>
>>>> I'm looking at THESE
>>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is
>>>> a push fit on the built in SMA connectors on the devices. I'm also
>>>> considering replacing the modified antennae with factory new units
>>>> and using the longer cables to mount them on opposite canopy rails
>>>> in the Stemme.Â* Those should be about a meter apart.
>>>>
>>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,
>>>>> it's not likely caused by jamming.
>>>>>
>>>>> I'm suspicious of your cut-down gps cables, those are tiny wires
>>>>> to be working on.
>>>>>
>>>>>
>>>>>
>>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
>>>>>> asked other local pilots and they don't report so many drop outs.
>>>>>>
>>>>>> Maybe there are just too many GPS antennae in my ship. I'll take
>>>>>> a look at a divider for everything except the ADS-B WAAS GPS.Â*
>>>>>> Its antenna is mounted aft of the engine in the Stemme. The rest
>>>>>> are on or under the glare shield.
>>>>>>
>>>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>>>> Thanks Tim
>>>>>>>>
>>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>>>
>>>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>>>> ClearNav
>>>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>>>> satellites" message.
>>>>>>>>
>>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>>>> Dan,
>>>>>>>>>
>>>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>>>> This will put you in the right area.
>>>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>>>> time.
>>>>>>>>>
>>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd,
>>>>>>>>> and leads to
>>>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>>>
>>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>>>> future by
>>>>>>>>> setting a longer fix interval, even 2 seconds might help, but
>>>>>>>>> no promises.
>>>>>>>>>
>>>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>>>> shown by the
>>>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>>>
>>>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>>>> happen as you
>>>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>>>
>>>>>>>>> I'm not saying this is what OLC are complaining about, just
>>>>>>>>> that it is odd
>>>>>>>>> and it might be.
>>>>>>>>>
>>>>>>>>> Tim.
>>>>>>>> --
>>>>>>>> Dan, 5J
>>>>>>> That smells of GPS jamming.
>>>>>>> Check this page.
>>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>>>> I did not have a problem with the vario file today. My antenna
>>>>>>> has a shortened cable to a MECA divider, then a short SMA-SMA
>>>>>>> link cable.
>>>>>>> Jim
>>>>>>
>>>>>
>>>>
>>>> --
>>>> Dan, 5J
>>>
>>
>

--
Dan, 5J

Dave Nadler

May 7th 19, 05:10 PM

On Tuesday, May 7, 2019 at 4:30:05 AM UTC-4, Tim Newport-Peace wrote:
> ... I have seen similar time sequence errors in other recorders over the years...

IIRC I've seen this from a number of GPS engines;
certainly I've got some Garmin engine logs like this.
The problem is naive software that doesn't filter
'obviously' wrong stuff from the GPS engine, including
time going backwards and stupendous position jumps.
Some nice example traces here momentarily detour
from Montana into the North Atlantic for example...

None of my collected examples were (to my best
understanding) related to jamming.

Its important not to trust too much the inputs ;-)

See ya, Dave

Tom Kelley #711

May 7th 19, 05:23 PM

On Tuesday, May 7, 2019 at 9:21:33 AM UTC-6, Dan Marotta wrote:
> An interesting thought, but I see the same whether I'm using the
> ClearNav or the ClearNav vario.Â* I doubt both could be experiencing the
> same fault at the same time.Â* It's really odd about the apparent time
> compression on the OLC display.Â* My flights score and appear just fine
> on skylines.aero.
>
> On 5/7/2019 8:21 AM, kinsell wrote:
> > Looking at your flight logs on OLC, you have the last two that didn't
> > validate, but others earlier this year that did.
> >
> > However, most of the altitude graphs are plotted with many hours of
> > dead time, with the flight being compressed into the very right hand
> > part of the graph. A very bizarre presentation.
> >
> > Perhaps your ClearNav has a hardware fault that is gradually getting
> > worse?
> >
> >
> >
> > On 5/6/19 4:20 PM, Dan Marotta wrote:
> >> These dropouts never occur during engine run which normally only runs
> >> 10 minutes or less from engine start to shutdown after takeoff.
> >>
> >> Heating up the dielectric is something I didn't consider.Â* Maybe I
> >> should replace the antennae...
> >>
> >> On 5/6/2019 11:39 AM, kinsell wrote:
> >>> On 5/6/19 10:32 AM, Dan Marotta wrote:
> >>>> I've also had drop outs with my Trig TN-70 and its antenna, though
> >>>> not as often as with my soaring GPSs.
> >>>
> >>> Do they correlate with the engine running?Â* If so, might be ignition
> >>> noise.
> >>>
> >>>
> >>>>
> >>>> Yes, the wires are tiny, but it was pretty simple to desolder them
> >>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
> >>>> did that for 3 antennae and they generally work fine, but lately
> >>>> have acting up.
> >>>
> >>> It's easy to overheat the dielectric in the coax, causing loss of
> >>> signal strength.
> >>>
> >>>
> >>>>
> >>>> I'm looking at THESE
> >>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
> >>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is
> >>>> a push fit on the built in SMA connectors on the devices. I'm also
> >>>> considering replacing the modified antennae with factory new units
> >>>> and using the longer cables to mount them on opposite canopy rails
> >>>> in the Stemme.Â* Those should be about a meter apart.
> >>>>
> >>>> On 5/6/2019 9:44 AM, kinsell wrote:
> >>>>> Jamming is directed skyward, they're not taking out car gps's in a
> >>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,
> >>>>> it's not likely caused by jamming.
> >>>>>
> >>>>> I'm suspicious of your cut-down gps cables, those are tiny wires
> >>>>> to be working on.
> >>>>>
> >>>>>
> >>>>>
> >>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
> >>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
> >>>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
> >>>>>> asked other local pilots and they don't report so many drop outs.
> >>>>>>
> >>>>>> Maybe there are just too many GPS antennae in my ship. I'll take
> >>>>>> a look at a divider for everything except the ADS-B WAAS GPS.Â*
> >>>>>> Its antenna is mounted aft of the engine in the Stemme. The rest
> >>>>>> are on or under the glare shield.
> >>>>>>
> >>>>>> On 5/5/2019 7:42 PM, JS wrote:
> >>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
> >>>>>>>> Thanks Tim
> >>>>>>>>
> >>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
> >>>>>>>>
> >>>>>>>> Strange that the igc file does not show GPS drop outs since my
> >>>>>>>> ClearNav
> >>>>>>>> screen went white with the caption (something like) No GPS. Zero
> >>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
> >>>>>>>> PowerFlarm portable screen also went blank with a "Zero
> >>>>>>>> satellites" message.
> >>>>>>>>
> >>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
> >>>>>>>>> Dan,
> >>>>>>>>>
> >>>>>>>>> Open your file with a text editor and search for "B190338"
> >>>>>>>>> This will put you in the right area.
> >>>>>>>>> In each record, after the letter B, the next six bytes are the
> >>>>>>>>> time.
> >>>>>>>>>
> >>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd,
> >>>>>>>>> and leads to
> >>>>>>>>> there being two records with a time of 190338, and also 190339.
> >>>>>>>>>
> >>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
> >>>>>>>>> future by
> >>>>>>>>> setting a longer fix interval, even 2 seconds might help, but
> >>>>>>>>> no promises.
> >>>>>>>>>
> >>>>>>>>> I am not seeing any GPS outage around that time. This would be
> >>>>>>>>> shown by the
> >>>>>>>>> Letter "A" in the 25th byte changing to a "V".
> >>>>>>>>>
> >>>>>>>>> Although it does not help a lot, the sequence error seems to
> >>>>>>>>> happen as you
> >>>>>>>>> left the ground, so I guess you were not reversing turns?
> >>>>>>>>>
> >>>>>>>>> I'm not saying this is what OLC are complaining about, just
> >>>>>>>>> that it is odd
> >>>>>>>>> and it might be.
> >>>>>>>>>
> >>>>>>>>> Tim.
> >>>>>>>> --
> >>>>>>>> Dan, 5J
> >>>>>>> That smells of GPS jamming.
> >>>>>>> Check this page.
> >>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
> >>>>>>> I did not have a problem with the vario file today. My antenna
> >>>>>>> has a shortened cable to a MECA divider, then a short SMA-SMA
> >>>>>>> link cable.
> >>>>>>> Jim
> >>>>>>
> >>>>>
> >>>>
> >>>> --
> >>>> Dan, 5J
> >>>
> >>
> >
>
> --
> Dan, 5J

Dan, my ClearNav XC logger, when downloaded to the OLC, appears to display the same as yours(time compression to the right). I used my Flarm IGC logger and it appears normal for the OLC. Yet on Skyline aero, Cross-country aero and See you, the ClearNav logger displays and views as normal.

The last several flights I have had experience GPS dropouts, which on Sunday seemed odd, and lasted only several minutes at a time(I fly out of KALM and the loss of signal was in numerous areas on Sunday). All the updates have been done, now several times over, yet the ClearNav logger and OLC just don't get along, yet the flight is scored and shows valid. Don't get an OLC speed when using the ClearNav.

When you figure this out, let us know!

Best. Tom #711

Dan Marotta

May 7th 19, 07:13 PM

Will do, Tom. Thanks.

I don't use the Flarm portable because it uses an SD card which is a
hassle and mine doesn't have an ENL license.Â* I'm not interested in
buying a license for such an old piece of equipment.Â* Besides, my
soaring income and bevy of chicks has not declined since having these
problems...

On 5/7/2019 10:23 AM, Tom Kelley #711 wrote:
> On Tuesday, May 7, 2019 at 9:21:33 AM UTC-6, Dan Marotta wrote:
>> An interesting thought, but I see the same whether I'm using the
>> ClearNav or the ClearNav vario.Â* I doubt both could be experiencing the
>> same fault at the same time.Â* It's really odd about the apparent time
>> compression on the OLC display.Â* My flights score and appear just fine
>> on skylines.aero.
>>
>> On 5/7/2019 8:21 AM, kinsell wrote:
>>> Looking at your flight logs on OLC, you have the last two that didn't
>>> validate, but others earlier this year that did.
>>>
>>> However, most of the altitude graphs are plotted with many hours of
>>> dead time, with the flight being compressed into the very right hand
>>> part of the graph. A very bizarre presentation.
>>>
>>> Perhaps your ClearNav has a hardware fault that is gradually getting
>>> worse?
>>>
>>>
>>>
>>> On 5/6/19 4:20 PM, Dan Marotta wrote:
>>>> These dropouts never occur during engine run which normally only runs
>>>> 10 minutes or less from engine start to shutdown after takeoff.
>>>>
>>>> Heating up the dielectric is something I didn't consider.Â* Maybe I
>>>> should replace the antennae...
>>>>
>>>> On 5/6/2019 11:39 AM, kinsell wrote:
>>>>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>>>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>>>>> not as often as with my soaring GPSs.
>>>>> Do they correlate with the engine running?Â* If so, might be ignition
>>>>> noise.
>>>>>
>>>>>
>>>>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>>>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>>>>> did that for 3 antennae and they generally work fine, but lately
>>>>>> have acting up.
>>>>> It's easy to overheat the dielectric in the coax, causing loss of
>>>>> signal strength.
>>>>>
>>>>>
>>>>>> I'm looking at THESE
>>>>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>>>>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is
>>>>>> a push fit on the built in SMA connectors on the devices. I'm also
>>>>>> considering replacing the modified antennae with factory new units
>>>>>> and using the longer cables to mount them on opposite canopy rails
>>>>>> in the Stemme.Â* Those should be about a meter apart.
>>>>>>
>>>>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,
>>>>>>> it's not likely caused by jamming.
>>>>>>>
>>>>>>> I'm suspicious of your cut-down gps cables, those are tiny wires
>>>>>>> to be working on.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>>>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
>>>>>>>> asked other local pilots and they don't report so many drop outs.
>>>>>>>>
>>>>>>>> Maybe there are just too many GPS antennae in my ship. I'll take
>>>>>>>> a look at a divider for everything except the ADS-B WAAS GPS.
>>>>>>>> Its antenna is mounted aft of the engine in the Stemme. The rest
>>>>>>>> are on or under the glare shield.
>>>>>>>>
>>>>>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>>>>>> Thanks Tim
>>>>>>>>>>
>>>>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>>>>>
>>>>>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>>>>>> ClearNav
>>>>>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>>>>>> satellites" message.
>>>>>>>>>>
>>>>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>>>>>> Dan,
>>>>>>>>>>>
>>>>>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>>>>>> This will put you in the right area.
>>>>>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>>>>>> time.
>>>>>>>>>>>
>>>>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd,
>>>>>>>>>>> and leads to
>>>>>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>>>>>
>>>>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>>>>>> future by
>>>>>>>>>>> setting a longer fix interval, even 2 seconds might help, but
>>>>>>>>>>> no promises.
>>>>>>>>>>>
>>>>>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>>>>>> shown by the
>>>>>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>>>>>
>>>>>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>>>>>> happen as you
>>>>>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>>>>>
>>>>>>>>>>> I'm not saying this is what OLC are complaining about, just
>>>>>>>>>>> that it is odd
>>>>>>>>>>> and it might be.
>>>>>>>>>>>
>>>>>>>>>>> Tim.
>>>>>>>>>> --
>>>>>>>>>> Dan, 5J
>>>>>>>>> That smells of GPS jamming.
>>>>>>>>> Check this page.
>>>>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>>>>>> I did not have a problem with the vario file today. My antenna
>>>>>>>>> has a shortened cable to a MECA divider, then a short SMA-SMA
>>>>>>>>> link cable.
>>>>>>>>> Jim
>>>>>> --
>>>>>> Dan, 5J
>> --
>> Dan, 5J
> Dan, my ClearNav XC logger, when downloaded to the OLC, appears to display the same as yours(time compression to the right). I used my Flarm IGC logger and it appears normal for the OLC. Yet on Skyline aero, Cross-country aero and See you, the ClearNav logger displays and views as normal.
>
> The last several flights I have had experience GPS dropouts, which on Sunday seemed odd, and lasted only several minutes at a time(I fly out of KALM and the loss of signal was in numerous areas on Sunday). All the updates have been done, now several times over, yet the ClearNav logger and OLC just don't get along, yet the flight is scored and shows valid. Don't get an OLC speed when using the ClearNav.
>
> When you figure this out, let us know!
>
> Best. Tom #711

--
Dan, 5J

kinsell

May 8th 19, 01:47 AM

On 5/7/19 10:10 AM, Dave Nadler wrote:
> On Tuesday, May 7, 2019 at 4:30:05 AM UTC-4, Tim Newport-Peace wrote:
>> ... I have seen similar time sequence errors in other recorders over the years...
>
> IIRC I've seen this from a number of GPS engines;
> certainly I've got some Garmin engine logs like this.
> The problem is naive software that doesn't filter
> 'obviously' wrong stuff from the GPS engine, including
> time going backwards and stupendous position jumps.
> Some nice example traces here momentarily detour
> from Montana into the North Atlantic for example...
>
> None of my collected examples were (to my best
> understanding) related to jamming.
>
> Its important not to trust too much the inputs ;-)
>
> See ya, Dave
>

I can't fault software for failing to filter out bad data. Having
submitted a number of logs to OLC from a cell phone, I don't see the
type of errors described here. Maybe better gps engines are in order?
Seems like producing good data is better than filtering out bad data.

Dan Marotta

May 8th 19, 03:58 PM

> I can't fault software for failing to filter out bad data.Â* Having
> submitted a number of logs to OLC from a cell phone, I don't see the
> type of errors described here.Â* Maybe better gps engines are in order?
> Seems like producing good data is better than filtering out bad data.

What you say has merit, but I can't see opening up my ClearNav computer
and vario and attempting to replace the GPS engines.

Since both and my PowerFlarm portable experience the drop outs, I've got
three new antennae on order.Â* We'll see how that works.

Funny how this just started happening in the end of April...
--
Dan, 5J

Martin Gregorie[_6_]

May 8th 19, 07:16 PM

On Wed, 08 May 2019 08:58:39 -0600, Dan Marotta wrote:

> Funny how this just started happening in the end of April...
>
I thought: have you got another logger you could leave running on the
field away from the runway but where it gets a decent signal?

If that also gets the time hiccup, then you'll know the problem is
outside the Stemme.

--
Martin | martin at
Gregorie | gregorie dot org

Dan Marotta

May 8th 19, 11:28 PM

I have a Dell Streak in the cockpit (right side) for my wife's use. It
also records an igc file which I can post on skylines.org.Â* It is not
acceptable to OLC due to no ENL recorder.Â* Maybe the XCSoar troops would
write a module to access the Streak's microphone and record engine
noise...Â* Or maybe one of the XCSoar clones already does that?

On 5/8/2019 12:16 PM, Martin Gregorie wrote:
> On Wed, 08 May 2019 08:58:39 -0600, Dan Marotta wrote:
>
>> Funny how this just started happening in the end of April...
>>
> I thought: have you got another logger you could leave running on the
> field away from the runway but where it gets a decent signal?
>
> If that also gets the time hiccup, then you'll know the problem is
> outside the Stemme.
>
>

--
Dan, 5J

kinsell

May 9th 19, 02:58 AM

I see a flight on Jan 27 this year that had the same highly compressed
altitude graph, so something wasn't right well before end of April.

Sounds like you've got problems due to jamming, in addition to at least
one other issue.

Should be plenty of other gliders flying out of Moriarty to compare logs
with. Suppose you could submit one from the Dell Streak and lie about
the glider type, then delete it after seeing how OLC likes it.

-Dave

On 5/8/19 4:28 PM, Dan Marotta wrote:
> I have a Dell Streak in the cockpit (right side) for my wife's use. It
> also records an igc file which I can post on skylines.org.Â* It is not
> acceptable to OLC due to no ENL recorder.Â* Maybe the XCSoar troops would
> write a module to access the Streak's microphone and record engine
> noise...Â* Or maybe one of the XCSoar clones already does that?
>
> On 5/8/2019 12:16 PM, Martin Gregorie wrote:
>> On Wed, 08 May 2019 08:58:39 -0600, Dan Marotta wrote:
>>
>>> Funny how this just started happening in the end of April...
>>>
>> I thought: have you got another logger you could leave running on the
>> field away from the runway but where it gets a decent signal?
>>
>> If that also gets the time hiccup, then you'll know the problem is
>> outside the Stemme.
>>
>>
>

Dan Marotta

May 9th 19, 03:38 PM

Good idea.Â* I noticed the time compression some time ago but chalked it
to OLC doing something new.Â* It's cloudy and rainy today but I need to
go to the airport anyway.Â* I'll get the Streak.

On 5/8/2019 7:58 PM, kinsell wrote:
> I see a flight on Jan 27 this year that had the same highly compressed
> altitude graph, so something wasn't right well before end of April.
>
> Sounds like you've got problems due to jamming, in addition to at
> least one other issue.
>
> Should be plenty of other gliders flying out of Moriarty to compare
> logs with.Â* Suppose you could submit one from the Dell Streak and lie
> about the glider type, then delete it after seeing how OLC likes it.
>
> -Dave
>
>
>
> On 5/8/19 4:28 PM, Dan Marotta wrote:
>> I have a Dell Streak in the cockpit (right side) for my wife's use.
>> It also records an igc file which I can post on skylines.org.Â* It is
>> not acceptable to OLC due to no ENL recorder.Â* Maybe the XCSoar
>> troops would write a module to access the Streak's microphone and
>> record engine noise...Â* Or maybe one of the XCSoar clones already
>> does that?
>>
>> On 5/8/2019 12:16 PM, Martin Gregorie wrote:
>>> On Wed, 08 May 2019 08:58:39 -0600, Dan Marotta wrote:
>>>
>>>> Funny how this just started happening in the end of April...
>>>>
>>> I thought: have you got another logger you could leave running on the
>>> field away from the runway but where it gets a decent signal?
>>>
>>> If that also gets the time hiccup, then you'll know the problem is
>>> outside the Stemme.
>>>
>>>
>>
>

--
Dan, 5J

kinsell

May 18th 19, 04:13 PM

On 5/7/19 10:23 AM, Tom Kelley #711 wrote:
> On Tuesday, May 7, 2019 at 9:21:33 AM UTC-6, Dan Marotta wrote:
>> An interesting thought, but I see the same whether I'm using the
>> ClearNav or the ClearNav vario.Â* I doubt both could be experiencing the
>> same fault at the same time.Â* It's really odd about the apparent time
>> compression on the OLC display.Â* My flights score and appear just fine
>> on skylines.aero.
>>
>> On 5/7/2019 8:21 AM, kinsell wrote:
>>> Looking at your flight logs on OLC, you have the last two that didn't
>>> validate, but others earlier this year that did.
>>>
>>> However, most of the altitude graphs are plotted with many hours of
>>> dead time, with the flight being compressed into the very right hand
>>> part of the graph. A very bizarre presentation.
>>>
>>> Perhaps your ClearNav has a hardware fault that is gradually getting
>>> worse?
>>>
>>>
>>>
>>> On 5/6/19 4:20 PM, Dan Marotta wrote:
>>>> These dropouts never occur during engine run which normally only runs
>>>> 10 minutes or less from engine start to shutdown after takeoff.
>>>>
>>>> Heating up the dielectric is something I didn't consider.Â* Maybe I
>>>> should replace the antennae...
>>>>
>>>> On 5/6/2019 11:39 AM, kinsell wrote:
>>>>> On 5/6/19 10:32 AM, Dan Marotta wrote:
>>>>>> I've also had drop outs with my Trig TN-70 and its antenna, though
>>>>>> not as often as with my soaring GPSs.
>>>>>
>>>>> Do they correlate with the engine running?Â* If so, might be ignition
>>>>> noise.
>>>>>
>>>>>
>>>>>>
>>>>>> Yes, the wires are tiny, but it was pretty simple to desolder them
>>>>>> from the puck, clip the cable to length, strip, tin, and solder.Â* I
>>>>>> did that for 3 antennae and they generally work fine, but lately
>>>>>> have acting up.
>>>>>
>>>>> It's easy to overheat the dielectric in the coax, causing loss of
>>>>> signal strength.
>>>>>
>>>>>
>>>>>>
>>>>>> I'm looking at THESE
>>>>>> <https://www.amazon.com/CIROCOMM-Antenna-Ceramic-25x25x2mm-Geekstory/dp/B078Y2WNY6?ref_=Oct_TopRatedC_3248676011_1&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28&pf_rd_s=merchandised-search-6&pf_rd_t=101&pf_rd_i=3248676011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_r=GNQVSWJ3FAVNDTDDJJDS&pf_rd_p=57ac2d87-b669-53fa-a2b6-2c15e8d66f28>
>>>>>> as replacements.Â* Any comments?Â* I wonder if that IPEX connector is
>>>>>> a push fit on the built in SMA connectors on the devices. I'm also
>>>>>> considering replacing the modified antennae with factory new units
>>>>>> and using the longer cables to mount them on opposite canopy rails
>>>>>> in the Stemme.Â* Those should be about a meter apart.
>>>>>>
>>>>>> On 5/6/2019 9:44 AM, kinsell wrote:
>>>>>>> Jamming is directed skyward, they're not taking out car gps's in a
>>>>>>> 400 nm radius.Â* If you're getting bad time stamps just at liftoff,
>>>>>>> it's not likely caused by jamming.
>>>>>>>
>>>>>>> I'm suspicious of your cut-down gps cables, those are tiny wires
>>>>>>> to be working on.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 5/6/19 9:08 AM, Dan Marotta wrote:
>>>>>>>> Yes, the GPS jamming usually centers around Alamogordo and ranges
>>>>>>>> out to about 400 nm.Â* Moriarty is well within that area.Â* I've
>>>>>>>> asked other local pilots and they don't report so many drop outs.
>>>>>>>>
>>>>>>>> Maybe there are just too many GPS antennae in my ship. I'll take
>>>>>>>> a look at a divider for everything except the ADS-B WAAS GPS.
>>>>>>>> Its antenna is mounted aft of the engine in the Stemme. The rest
>>>>>>>> are on or under the glare shield.
>>>>>>>>
>>>>>>>> On 5/5/2019 7:42 PM, JS wrote:
>>>>>>>>> On Sunday, May 5, 2019 at 3:43:24 PM UTC-7, Dan Marotta wrote:
>>>>>>>>>> Thanks Tim
>>>>>>>>>>
>>>>>>>>>> I'll increase my time interval to 2 seconds and see if that helps.
>>>>>>>>>>
>>>>>>>>>> Strange that the igc file does not show GPS drop outs since my
>>>>>>>>>> ClearNav
>>>>>>>>>> screen went white with the caption (something like) No GPS. Zero
>>>>>>>>>> satellites.Â* And the ClearNav vario said, "Warning no GPS". The
>>>>>>>>>> PowerFlarm portable screen also went blank with a "Zero
>>>>>>>>>> satellites" message.
>>>>>>>>>>
>>>>>>>>>> On 5/5/2019 1:05 PM, Tim Newport-Peace wrote:
>>>>>>>>>>> Dan,
>>>>>>>>>>>
>>>>>>>>>>> Open your file with a text editor and search for "B190338"
>>>>>>>>>>> This will put you in the right area.
>>>>>>>>>>> In each record, after the letter B, the next six bytes are the
>>>>>>>>>>> time.
>>>>>>>>>>>
>>>>>>>>>>> After B190339 the time jumps back toÂ* B190337, which is odd,
>>>>>>>>>>> and leads to
>>>>>>>>>>> there being two records with a time of 190338, and also 190339.
>>>>>>>>>>>
>>>>>>>>>>> Odd, but I have seen this before. Maybe you can avoid it in
>>>>>>>>>>> future by
>>>>>>>>>>> setting a longer fix interval, even 2 seconds might help, but
>>>>>>>>>>> no promises.
>>>>>>>>>>>
>>>>>>>>>>> I am not seeing any GPS outage around that time. This would be
>>>>>>>>>>> shown by the
>>>>>>>>>>> Letter "A" in the 25th byte changing to a "V".
>>>>>>>>>>>
>>>>>>>>>>> Although it does not help a lot, the sequence error seems to
>>>>>>>>>>> happen as you
>>>>>>>>>>> left the ground, so I guess you were not reversing turns?
>>>>>>>>>>>
>>>>>>>>>>> I'm not saying this is what OLC are complaining about, just
>>>>>>>>>>> that it is odd
>>>>>>>>>>> and it might be.
>>>>>>>>>>>
>>>>>>>>>>> Tim.
>>>>>>>>>> --
>>>>>>>>>> Dan, 5J
>>>>>>>>> That smells of GPS jamming.
>>>>>>>>> Check this page.
>>>>>>>>> https://www.navcen.uscg.gov/pdf/gps/gpsnotices/GPS_Interference.pdf
>>>>>>>>> I did not have a problem with the vario file today. My antenna
>>>>>>>>> has a shortened cable to a MECA divider, then a short SMA-SMA
>>>>>>>>> link cable.
>>>>>>>>> Jim
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> Dan, 5J
>>>>>
>>>>
>>>
>>
>> --
>> Dan, 5J
>
> Dan, my ClearNav XC logger, when downloaded to the OLC, appears to display the same as yours(time compression to the right). I used my Flarm IGC logger and it appears normal for the OLC. Yet on Skyline aero, Cross-country aero and See you, the ClearNav logger displays and views as normal.
>
> The last several flights I have had experience GPS dropouts, which on Sunday seemed odd, and lasted only several minutes at a time(I fly out of KALM and the loss of signal was in numerous areas on Sunday). All the updates have been done, now several times over, yet the ClearNav logger and OLC just don't get along, yet the flight is scored and shows valid. Don't get an OLC speed when using the ClearNav.
>
> When you figure this out, let us know!
>
> Best. Tom #711
>

Your May 3 flight is interesting. Hours worth of altitude data is
missing on the OLC graph, but the rest of the trace is shown. This is
different than the altitude data being compressed to the right.

Looking at the GPS altitude on SeeYou, there's one dropout of data
towards the end of the flight, apparently at the point where OLC started
showing altitude data on their graph.

So maybe one short loss of data is screwing up the OLC scoring and graphing.

Tom Kelley #711

May 18th 19, 05:19 PM

On Sunday, May 5, 2019 at 9:38:57 AM UTC-6, Dan Marotta wrote:
> For my last three flights I've been getting a message from OLC warning
> of implausible time records in the igc file.Â* Does anyone know what this
> means and what I might do to correct the problem? I've asked the
> question on the ClearNav forum but haven't gotten a reply yet.
>
> Here's a link to the file if that helps:
> https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
> --
> Dan, 5J

I sent my CN XC IGC 5-5-19 flight to a friend which when I posted it to the OLC did the same compression as the 5-3-19 flight did. When he posted it, it showed normal....ya. Now the CN XC IGC flight on 5-15-19 did the same compression to the right. So, I used the Flarm IGC file again on the OLC.
See You shows the files are valid on the CN XC IGC loggers and when altitude is checked shows fine. OLC gives 2 green circles with all the CN XC files..

I never had this problem before until I did the last update over winter with the CN XC Vario IGC logger. Yesterday I sent T8 the IGC logger file from 5-15-19 and they will be looking into it.

On the 5-15-19 flight, I did have GPS drop out several times, but the Flarm IGC logger doesn't seem to get affected for the OLC. Also, had several F-16's fly by and a B-1B bomber come right under me. I do know where ever I fly, with my transponder, my altitude is always getting shown by certain folks playing war games. On the B-1B I couldn't see through the cockpit windows to see what color helmets they had on...........!

Best. Tom @711.

Dan Marotta

May 18th 19, 06:42 PM

Is there a way to roll back to the previous versions of CN2 and CNvXC?

On 5/18/2019 10:19 AM, Tom Kelley #711 wrote:
> On Sunday, May 5, 2019 at 9:38:57 AM UTC-6, Dan Marotta wrote:
>> For my last three flights I've been getting a message from OLC warning
>> of implausible time records in the igc file.Â* Does anyone know what this
>> means and what I might do to correct the problem? I've asked the
>> question on the ClearNav forum but haven't gotten a reply yet.
>>
>> Here's a link to the file if that helps:
>> https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
>> --
>> Dan, 5J
> I sent my CN XC IGC 5-5-19 flight to a friend which when I posted it to the OLC did the same compression as the 5-3-19 flight did. When he posted it, it showed normal....ya. Now the CN XC IGC flight on 5-15-19 did the same compression to the right. So, I used the Flarm IGC file again on the OLC.
> See You shows the files are valid on the CN XC IGC loggers and when altitude is checked shows fine. OLC gives 2 green circles with all the CN XC files.
>
> I never had this problem before until I did the last update over winter with the CN XC Vario IGC logger. Yesterday I sent T8 the IGC logger file from 5-15-19 and they will be looking into it.
>
> On the 5-15-19 flight, I did have GPS drop out several times, but the Flarm IGC logger doesn't seem to get affected for the OLC. Also, had several F-16's fly by and a B-1B bomber come right under me. I do know where ever I fly, with my transponder, my altitude is always getting shown by certain folks playing war games. On the B-1B I couldn't see through the cockpit windows to see what color helmets they had on...........!
>
> Best. Tom @711.

--
Dan, 5J

Tango Eight

May 19th 19, 11:22 AM

A possible work around is to download your flight using an alternate time interval. CN flight recorders store internally at one second, can d/l at user selectable intrval up to 8 sec (iirc).

Best,

Evan Ludeman

[email protected]

May 19th 19, 02:03 PM

Dan,
Just FYI, I got the same error last night on an IGC flle from an Lx9070, so it may not be a CN issue.
lx9070 was updated to latest software version on 4/8/19.

This is what I see in my file:
B1813373310143N08621921WA0103001106006001113851177 3067-006602030130-041003
B1813383310151N08621903WA0103001106007004113561204 1053-004602030130-043003
B1813393310164N08621887WA0103001107006004111961228 5040-003602030130-042003
LLXVCLOCKJUMP
B1813373310179N08621875WA0103101107006004110891250 7026-003602030120-039003
B1813383310197N08621867WA0103201107006004110021274 0014-004102030120-038001
B1813393310216N08621863WA0103101107006004109261299 2002-004102030120-034001

kinsell

May 19th 19, 03:12 PM

Looks like both you and Dan show a UBLOX NEO as the GPS receiver, maybe
a problem with new firmware from the vendor?

On 5/19/19 7:03 AM, wrote:
> Dan,
> Just FYI, I got the same error last night on an IGC flle from an Lx9070, so it may not be a CN issue.
> lx9070 was updated to latest software version on 4/8/19.
>
> This is what I see in my file:
> B1813373310143N08621921WA0103001106006001113851177 3067-006602030130-041003
> B1813383310151N08621903WA0103001106007004113561204 1053-004602030130-043003
> B1813393310164N08621887WA0103001107006004111961228 5040-003602030130-042003
> LLXVCLOCKJUMP
> B1813373310179N08621875WA0103101107006004110891250 7026-003602030120-039003
> B1813383310197N08621867WA0103201107006004110021274 0014-004102030120-038001
> B1813393310216N08621863WA0103101107006004109261299 2002-004102030120-034001
>

Dan Marotta

May 19th 19, 03:30 PM

Thanks Evan.Â* As a retired Systems Engineer, I've made a lot of work
arounds and they're not very satisfying.Â* The problem needs to be fixed.

If it's from the GPS engine manufacturer, they should fix it.Â* Do both
the vario and the CN2 computer use the same GPS?Â* It seems unlikely that
both CN and LX would make the same error in their code.

I'll look into a longer download interval but how about my previous
question?Â* Is there a way to roll back to the previous firmware versions.

On 5/19/2019 4:22 AM, Tango Eight wrote:
> A possible work around is to download your flight using an alternate time interval. CN flight recorders store internally at one second, can d/l at user selectable intrval up to 8 sec (iirc).
>
> Best,
>
> Evan Ludeman

--
Dan, 5J

[email protected]

May 19th 19, 05:38 PM

FYI, Iâ€™ve sent my file to Lxnav to see what they think.
My backup IGC file from the portable power Flarm was ok during the same time period and was accepted by OLC.

[email protected]

May 20th 19, 01:43 PM

Kinsell, You may be on the right track.
Backup recorder (portable powerflarm) with separate gps system, recorded fine during the same period.

kinsell

May 20th 19, 04:09 PM

On 5/20/19 6:43 AM, wrote:
> Kinsell, You may be on the right track.
> Backup recorder (portable powerflarm) with separate gps system, recorded fine during the same period.
>

I notice your Oct 2 2018 flight on OLC had that peculiar highly
compressed altitude graph, but without the gps altitude dropouts. Maybe
that's just some unrelated OLC display issue.

Ublox receivers are used for many other applications besides flight
recorders, wonder why nobody else seems to be having problems.

I've been submitting from a PF Core the last few years, haven't seen any
of these issues.

[email protected]

May 20th 19, 04:45 PM

Ref >.
>I notice your Oct 2 2018 flight on OLC had that peculiar highly
>compressed altitude graph, but without the gps altitude dropouts. Maybe
>that's just some unrelated OLC display issue.

Good observation, I didnâ€™t notice that.
The one on 10/4 has the same compressed altitude issue, while the one on 10/3 looks ok, as does the flight on 5/1/19.
I have been posting to OLC from that particular 9070 for about 4 years and havenâ€™t had a problem before now.

MS

kinsell

May 20th 19, 08:05 PM

On 5/20/19 9:45 AM, wrote:
> Ref >.
>> I notice your Oct 2 2018 flight on OLC had that peculiar highly
>> compressed altitude graph, but without the gps altitude dropouts. Maybe
>> that's just some unrelated OLC display issue.
>
> Good observation, I didnâ€™t notice that.
> The one on 10/4 has the same compressed altitude issue, while the one on 10/3 looks ok, as does the flight on 5/1/19.
> I have been posting to OLC from that particular 9070 for about 4 years and havenâ€™t had a problem before now.
>
> MS
>

Also I notice your Oct 2 log had a 2 second backwards jump in the time
stamp, nicely pointed out by a CLOCKJUMP message.

B1836063309906N08617890WA0079300914008999092601063 91370014102310100
B1836073309895N08617877WA0079700918008999099341052 61320019502310100
B1836083309885N08617862WA0080100922008999096891031 41260027202310100
B1836093309877N08617847WA0080400926008999097381021 11210032602300100
LLXVCLOCKJUMP
B1836073309869N08617831WA0080900931008999091120999 41150032402300110
B1836083309863N08617815WA0081500936008999087500984 01100029902300090
B1836093309859N08617798WA0081800940008999092360980 91040030802290090
B1836103309856N08617781WA0082200942008999096080987 51000036802290080

So these problems have been around for quite a while, maybe OLC just
started flagging them as fatal errors?

kinsell

May 20th 19, 08:28 PM

On 5/20/19 1:05 PM, kinsell wrote:
> On 5/20/19 9:45 AM, wrote:
>> Ref >.
>>> I notice your Oct 2 2018 flight on OLC had that peculiar highly
>>> compressed altitude graph, but without the gps altitude dropouts.Â* Maybe
>>> that's just some unrelated OLC display issue.
>>
>> Good observation, I didnâ€™t notice that.
>> The one on 10/4 has the same compressed altitude issue, while the one
>> on 10/3 looks ok, as does the flight on 5/1/19.
>> I have been posting to OLC from that particular 9070 for about 4 years
>> and havenâ€™t had a problem before now.
>>
>> MS
>>
>
> Also I notice your Oct 2 log had a 2 second backwards jump in the time
> stamp, nicely pointed out by a CLOCKJUMP message.
>
>
> B1836063309906N08617890WA0079300914008999092601063 91370014102310100
> B1836073309895N08617877WA0079700918008999099341052 61320019502310100
> B1836083309885N08617862WA0080100922008999096891031 41260027202310100
> B1836093309877N08617847WA0080400926008999097381021 11210032602300100
> LLXVCLOCKJUMP
> B1836073309869N08617831WA0080900931008999091120999 41150032402300110
> B1836083309863N08617815WA0081500936008999087500984 01100029902300090
> B1836093309859N08617798WA0081800940008999092360980 91040030802290090
> B1836103309856N08617781WA0082200942008999096080987 51000036802290080
>
>
>
> So these problems have been around for quite a while, maybe OLC just
> started flagging them as fatal errors?

Looking at your Aug 2 2017 flight, it shows the same compressed altitude
graph, and another 2 second backwards jump in a time stamp. Wow.

Charlie M. (UH & 002 owner/pilot)

May 20th 19, 08:41 PM

Maybe he is exceeding VNE by a lot and going back in time? I wonder what Doc Brown would say.....LOL...

[email protected]

May 20th 19, 09:42 PM

Iâ€™ve not heard back from Lxnav yet, but I had a private email from a very smart person that pointed out that both the October 2 and October 4 flights had the clock jump after takeoff but before soaring began. The flight this week had the clock jump a minute or so after soaring began, and thus is likely why OLC flagged this one and not the other two. It appears that the clock jump is 7 to 8 minutes after the unit is turned on. Since I generally do not turn the system on until just before takeoff, it is believed that the system is using an internal clock until it syncs with the gps satellites and then resets the clock which may be different by a couple of seconds. My plan is to turn the 9070 on a few minutes before launch to allow it to sync clocks to see if that helps. It is not clear to me if Danâ€™s issue is similar to mine or different.

MS

Dan Marotta

May 20th 19, 10:05 PM

That's certainly worth a try.Â* My normal method is to saddle up, start
the engine, and turn on the CN2, the CN vario, and the PowerFlarm
portable (which does not have an ENL license).Â* Then I run checklists
and taxi out and, as soon as the temperatures are in the green, take
off.Â* I'll try turning on the computers first and take my time with
getting started and to the hold short line.Â* I'll shoot for 10 minutes
and see how that goes.

On 5/20/2019 2:42 PM, wrote:
> Iâ€™ve not heard back from Lxnav yet, but I had a private email from a very smart person that pointed out that both the October 2 and October 4 flights had the clock jump after takeoff but before soaring began. The flight this week had the clock jump a minute or so after soaring began, and thus is likely why OLC flagged this one and not the other two. It appears that the clock jump is 7 to 8 minutes after the unit is turned on. Since I generally do not turn the system on until just before takeoff, it is believed that the system is using an internal clock until it syncs with the gps satellites and then resets the clock which may be different by a couple of seconds. My plan is to turn the 9070 on a few minutes before launch to allow it to sync clocks to see if that helps. It is not clear to me if Danâ€™s issue is similar to mine or different.
>
> MS

--
Dan, 5J

[email protected]

May 20th 19, 10:06 PM

On Monday, May 20, 2019 at 4:42:52 PM UTC-4, wrote:
> Iâ€™ve not heard back from Lxnav yet, but I had a private email from a very smart person that pointed out that both the October 2 and October 4 flights had the clock jump after takeoff but before soaring began. The flight this week had the clock jump a minute or so after soaring began, and thus is likely why OLC flagged this one and not the other two. It appears that the clock jump is 7 to 8 minutes after the unit is turned on. Since I generally do not turn the system on until just before takeoff, it is believed that the system is using an internal clock until it syncs with the gps satellites and then resets the clock which may be different by a couple of seconds. My plan is to turn the 9070 on a few minutes before launch to allow it to sync clocks to see if that helps. It is not clear to me if Danâ€™s issue is similar to mine or different.
>
> MS

We've established in another thread some months ago that the display of altitudes of a flight within the OLC web page is all messed up if OLC thinks that the flight "started" later, at some higher logged altitude, rather than at the altitude of the declared takeoff airport. (Typically due to the flight recorder not getting a GPS fix - or not being turned on at all - until after takeoff.) I am still of the opinion that this should be considered a bug in OLC, since it can "see" that the start location (lat/lon as well as altitude) is not at the airport. The altitudes inside the flight log file, even as downloaded from OLC, are still OK. Perhaps the time jump, too, makes OLC think it's a new "takeoff", and thus has similar consequences in its display (plus its "implausible" warning).

But I don't quite understand the conjecture that "the system is using an internal clock until it syncs with the gps satellites", because prior to getting a GPS fix the flight recorder shouldn't be recording locations into the flight log either, no?

kinsell

May 20th 19, 10:27 PM

On 5/20/19 2:42 PM, wrote:
> Iâ€™ve not heard back from Lxnav yet, but I had a private email from a very smart person that pointed out that both the October 2 and October 4 flights had the clock jump after takeoff but before soaring began. The flight this week had the clock jump a minute or so after soaring began, and thus is likely why OLC flagged this one and not the other two. It appears that the clock jump is 7 to 8 minutes after the unit is turned on. Since I generally do not turn the system on until just before takeoff, it is believed that the system is using an internal clock until it syncs with the gps satellites and then resets the clock which may be different by a couple of seconds. My plan is to turn the 9070 on a few minutes before launch to allow it to sync clocks to see if that helps. It is not clear to me if Danâ€™s issue is similar to mine or different.
>
> MS
>

They do have clocks to help achieve lock on the satellites, but I've
seen the reported time jump immediately after lock was achieved. Don't
know why the 9070 would wait minutes after achieving lock before
correcting the time. Maybe an issue of 2D vs 3D lock. If you're
turning on the logger immediately before takeoff, you're risking losing
the early part of the flight entirely, not just having time problems.

Dan was having lots of gps altitude dropouts during flights, that might
just be jamming. He did have a time jump just at liftoff, so that fits
in with switching the clocks.

[email protected]

May 20th 19, 11:03 PM

>But I don't quite understand the conjecture that "the system is using an internal clock until it syncs with the gps satellites", because prior to getting a GPS fix the >flight recorder shouldn't be recording locations into the flight log either, no?

Yes, the system seems to have a fix on the satellites and the Lat/Lon/Alt seems to be consistent from one record to another. It certainly doesnâ€™t take several minutes for the system to get a gps fix. The question is why does it record an incremental time for a few minutes and then resets the time by a couple of seconds. It would seem the system should record the time stamp directly from the gps. If it did that, how could sequential time records change? Is it possible the gps starts with an internal clock number initially and then after a few minutes makes a comparison check with the clock from the gps? It gets back to Kensellâ€™s point about how the gps system is handling the data and or the firmware is using the info inside the computers. These seem like good questions for vendors which I hope to get soon.

Tim Newport-Peace[_6_]

May 20th 19, 11:09 PM

At 21:27 20 May 2019, kinsell wrote:
>On 5/20/19 2:42 PM, wrote:
>> Iâ€™ve not heard back from Lxnav yet, but I had a private email from a
>very smart person that pointed out that both the October 2 and October 4
>flights had the clock jump after takeoff but before soaring began. The
>flight this week had the clock jump a minute or so after soaring began,
and
>thus is likely why OLC flagged this one and not the other two. It
appears
>that the clock jump is 7 to 8 minutes after the unit is turned on. Since
I
>generally do not turn the system on until just before takeoff, it is
>believed that the system is using an internal clock until it syncs with
the
>gps satellites and then resets the clock which may be different by a
couple
>of seconds. My plan is to turn the 9070 on a few minutes before launch
to
>allow it to sync clocks to see if that helps. It is not clear to me if
>Danâ€™s issue is similar to mine or different.
>>
>> MS
>>
>
>They do have clocks to help achieve lock on the satellites, but I've
>seen the reported time jump immediately after lock was achieved. Don't
>know why the 9070 would wait minutes after achieving lock before
>correcting the time. Maybe an issue of 2D vs 3D lock. If you're
>turning on the logger immediately before takeoff, you're risking losing
>the early part of the flight entirely, not just having time problems.
>
>Dan was having lots of gps altitude dropouts during flights, that might
>just be jamming. He did have a time jump just at liftoff, so that fits
>in with switching the clocks.
>
I've looked at Dan's trace, and the dropouts are in the latter part of the
flight,
nowhere near the time when the clock problem occurs, so probably not
jamming. Micheal's flight shows no GPs dropouts at all, but still
experienced
the problem.

[email protected]

May 20th 19, 11:11 PM

> If you're turning on the logger immediately before takeoff, you're risking losing
>the early part of the flight entirely, not just having time problems.

Good point. Iâ€™m not usually worried about the igc file much for casual flights which is what these all were. Or at least I wasnâ€™t worried until the OLC problem.
Of course for record, badge, or contest flights; I turn the computer and backup loggers on long before takeoff since tasks have to be entered and checked.
You may be on the right track with the 2D vs 3D lock. I will try to look at the gps satellite status page before takeoff in the future.

Dan Marotta

May 21st 19, 12:35 AM

So...Â* Does having a 3D fix with, say 8 satellites, constitute good GPS
time?Â* I would think so.

On 5/20/2019 3:27 PM, kinsell wrote:
> On 5/20/19 2:42 PM, wrote:
>> Iâ€™ve not heard back from Lxnav yet, but I had a private email from a
>> very smart person that pointed out that both the October 2 and
>> October 4 flights had the clock jump after takeoff but before soaring
>> began.Â* The flight this week had the clock jump a minute or so after
>> soaring began, and thus is likely why OLC flagged this one and not
>> the other two.Â* It appears that the clock jump is 7 to 8 minutes
>> after the unit is turned on.Â* Since I generally do not turn the
>> system on until just before takeoff, it is believed that the system
>> is using an internal clock until it syncs with the gps satellites and
>> then resets the clock which may be different by a couple of seconds.
>> My plan is to turn the 9070 on a few minutes before launch to allow
>> it to sync clocks to see if that helps.Â* It is not clear to me if
>> Danâ€™s issue is similar to mine or different.
>>
>> MS
>>
>
> They do have clocks to help achieve lock on the satellites, but I've
> seen the reported time jump immediately after lock was achieved.Â*
> Don't know why the 9070 would wait minutes after achieving lock before
> correcting the time.Â* Maybe an issue of 2D vs 3D lock.Â* If you're
> turning on the logger immediately before takeoff, you're risking
> losing the early part of the flight entirely, not just having time
> problems.
>
> Dan was having lots of gps altitude dropouts during flights, that
> might just be jamming.Â* He did have a time jump just at liftoff, so
> that fits in with switching the clocks.

--
Dan, 5J

Dave Leonard

May 21st 19, 03:34 AM

Maybe has to do with waiting to get the current almanac to know how many leap seconds to apply to received GPS time to get to UTC time used for the logs? Waiting for the whole message can take over 10 minutes.

On Monday, May 20, 2019 at 6:38:44 PM UTC-6, kinsell wrote:
> You would think 8 satellites would be plenty. Looking at some
> discussion on the Ublox site, apparently it's more complicated than time
> valid vs not valid. There's flags that differentiate between low
> accuracy satellite time vs high accuracy. Probably of no significance
> in our application. I'll bet the FR code could be tweeked to use
> satellite time when they're recording x-y-z data.
>
> Or you could be more conservative in making sure the gps is fully locked
> up before takeoff, works for me. My recorders come on with the master,
> by the time I'm ready for takeoff they've had plenty of time and
> checking the displays confirms that.
>
>
>
>

Dave Leonard

May 21st 19, 04:06 AM

Check the discussion here:
https://portal.u-blox.com/s/question/0D52p00008HKCbFCAX/what-is-time-error-if-utc-fully-resolved-flag-not-asserted

On Monday, May 20, 2019 at 8:34:07 PM UTC-6, Dave Leonard wrote:
> Maybe has to do with waiting to get the current almanac to know how many leap seconds to apply to received GPS time to get to UTC time used for the logs? Waiting for the whole message can take over 10 minutes.
>
>

[email protected]

May 21st 19, 01:54 PM

>Maybe has to do with waiting to get the current almanac to know how many leap seconds to apply to received GPS time to get to UTC time used for the logs? >Waiting for the whole message can take over 10 minutes.

Dave, thanks for the info and link. I had no idea about the gps errors, inaccuracies, atomic clock drift, leap seconds, etc; until doing a few searches.
Now I see why the clock time can change and have a greater appreciation for the difficulty GPS receiver manufacturers must deal with. It appears our real problem is that OLC does not know how to handle normal events within the log files. Other soaring analysis programs seem to know to expect such events.

I had an email from lxnav that they noticed this issue a few weeks ago. While I updated on April 8; there is a new May 7 update that should help.

Dan Marotta

May 21st 19, 03:23 PM

Well then, since I rig the wings in the hangar area and then tow the
glider to the apron for final prep before take off, I'll turn on the CN
devices at that time.Â* Some times it's an hour or more before I take
off.Â* That should give the hardware plenty of time to figure out what
time it is.

Griping hat on...Â* We're not planning a nuclear strike here, just
getting bragging rights about a meaningless fun flight.Â* It's ridiculous
that OLC acts like the bully on the play ground, enforcing unnecessary
rules.Â* Griping hat off...

On 5/20/2019 9:06 PM, Dave Leonard wrote:
> Check the discussion here:
> https://portal.u-blox.com/s/question/0D52p00008HKCbFCAX/what-is-time-error-if-utc-fully-resolved-flag-not-asserted
>
>
> On Monday, May 20, 2019 at 8:34:07 PM UTC-6, Dave Leonard wrote:
>> Maybe has to do with waiting to get the current almanac to know how many leap seconds to apply to received GPS time to get to UTC time used for the logs? Waiting for the whole message can take over 10 minutes.
>>
>>

--
Dan, 5J

kinsell

May 21st 19, 06:42 PM

On 5/20/19 9:06 PM, Dave Leonard wrote:
> Check the discussion here:
> https://portal.u-blox.com/s/question/0D52p00008HKCbFCAX/what-is-time-error-if-utc-fully-resolved-flag-not-asserted
>
>
> On Monday, May 20, 2019 at 8:34:07 PM UTC-6, Dave Leonard wrote:
>> Maybe has to do with waiting to get the current almanac to know how many leap seconds to apply to received GPS time to get to UTC time used for the logs? Waiting for the whole message can take over 10 minutes.
>>
>>

Yes, but the number of leap seconds to apply changes so infrequently
that it's silly to wait for that information to be downloaded at each
powerup.

GPS engines are free to store almanac and ephemeris data and shorten the
initialization time considerably, many of them do. I would say that the
Ublox behavior of waiting 10 minutes plus after achieving a 3D lock to
do corrections to the time is out of the ordinary.

So we have the perfect storm of a slow gps engine, pilots who don't
think they need to wait for the gps to lock up before takeoff, and OLC
doing stringent checking on the quality of the data. Of those three, I
would say OLC is the least at fault in all this.

kinsell

May 22nd 19, 03:54 PM

On 5/21/19 11:42 AM, kinsell wrote:
> On 5/20/19 9:06 PM, Dave Leonard wrote:
>> Check the discussion here:
>> https://portal.u-blox.com/s/question/0D52p00008HKCbFCAX/what-is-time-error-if-utc-fully-resolved-flag-not-asserted
>>
>>
>>
>> On Monday, May 20, 2019 at 8:34:07 PM UTC-6, Dave Leonard wrote:
>>> Maybe has to do with waiting to get the current almanac to know how
>>> many leap seconds to apply to received GPS time to get to UTC time
>>> used for the logs? Waiting for the whole message can take over 10
>>> minutes.
>>>
>>>
>
> Yes, but the number of leap seconds to apply changes so infrequently
> that it's silly to wait for that information to be downloaded at each
> powerup.
>
> GPS engines are free to store almanac and ephemeris data and shorten the
> initialization time considerably, many of them do.Â* I would say that the
> Ublox behavior of waiting 10 minutes plus after achieving a 3D lock to
> do corrections to the time is out of the ordinary.
>
> So we have the perfect storm of a slow gps engine, pilots who don't
> think they need to wait for the gps to lock up before takeoff, and OLC
> doing stringent checking on the quality of the data.Â* Of those three, I
> would say OLC is the least at fault in all this.

As a side note, I've used Ublox engines for Stratux boxes, was quite
happy with them. They seemed sensitive, quick to lock up, and certainly
were dirt cheap. Maybe they do cache the almanac data, but have some
bug in them that explains the big delay in getting the time right.

Tango Eight

May 23rd 19, 01:24 PM

I don't have time to catch up on this thread right now but good job on the leap second issue.

CN flight recorders update the UTC offset typically around five minutes after GPS lock.

Short term work around is to power up more than five minutes before launch, use 4 second record interval (which should mask the problem if the offset change happens in flight).

This is preliminary info... but seems to fit all the observed problems so far.

Best regard,
Evan Ludeman for CNi

Dan Marotta

May 23rd 19, 03:27 PM

Thanks Evan.

Out of town visitors and typical spring winds at Moriarty have kept me
on the ground.Â* Maybe Sunday...

On 5/23/2019 6:24 AM, Tango Eight wrote:
> I don't have time to catch up on this thread right now but good job on the leap second issue.
>
> CN flight recorders update the UTC offset typically around five minutes after GPS lock.
>
> Short term work around is to power up more than five minutes before launch, use 4 second record interval (which should mask the problem if the offset change happens in flight).
>
> This is preliminary info... but seems to fit all the observed problems so far.
>
> Best regard,
> Evan Ludeman for CNi
>
>

--
Dan, 5J

Dan Marotta

May 26th 19, 01:58 AM

I turned on my CN2 and CNvXC 20 minutes before engine start today. Then
it was another 15 minutes to warm up the engine before take off.Â* Even
though I had several GPS drop outs during the flight, it scored
perfectly.Â* BTW, all other devices in the cockpit, including my buddy's
iPad also lost GPS for those times.Â* Looks like the work around is to
let the GPSs get time synchronized before take off.

On 5/5/2019 9:38 AM, Dan Marotta wrote:
> For my last three flights I've been getting a message from OLC warning
> of implausible time records in the igc file.Â* Does anyone know what
> this means and what I might do to correct the problem? I've asked the
> question on the ClearNav forum but haven't gotten a reply yet.
>
> Here's a link to the file if that helps:
> https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0

--
Dan, 5J

kinsell

May 26th 19, 03:38 AM

On 5/25/19 6:58 PM, Dan Marotta wrote:
> I turned on my CN2 and CNvXC 20 minutes before engine start today. Then
> it was another 15 minutes to warm up the engine before take off.Â* Even
> though I had several GPS drop outs during the flight, it scored
> perfectly.Â* BTW, all other devices in the cockpit, including my buddy's
> iPad also lost GPS for those times.Â* Looks like the work around is to
> let the GPSs get time synchronized before take off.
>
> On 5/5/2019 9:38 AM, Dan Marotta wrote:
>> For my last three flights I've been getting a message from OLC warning
>> of implausible time records in the igc file.Â* Does anyone know what
>> this means and what I might do to correct the problem? I've asked the
>> question on the ClearNav forum but haven't gotten a reply yet. the
>>
>> Here's a link to the file if that helps:
>> https://www.dropbox.com/s/erm01jilimuqudd/2019-05-04-CNI-V8Q-01.IGC?dl=0
>

Do the dropouts match up with published times for GPS jamming? Your
trace shows tons of gps altitude dropouts between about 15:00 and 16:00
local time, but clean otherwise. They do correspond to the NE leg of
your flight, but that may just be coincidence.

Tim Newport-Peace[_6_]

May 26th 19, 11:04 AM

At 02:38 26 May 2019, kinsell wrote:
>On 5/25/19 6:58 PM, Dan Marotta wrote:
>> I turned on my CN2 and CNvXC 20 minutes before engine start today. Then

>> it was another 15 minutes to warm up the engine before take off.Â* Even

>> though I had several GPS drop outs during the flight, it scored
>> perfectly.Â* BTW, all other devices in the cockpit, including my buddy's

>> iPad also lost GPS for those times.Â* Looks like the work around is to
>> let the GPSs get time synchronized before take off.
>>
Basically, the Time in the IGC file originates in the GPS Engine. At
power-up it comes from the RTC, but once 'Satellite Time' has been received
and the correct number of Leap Seconds applied, the source switches to
that.

The difference can be in the order of 2 seconds, and this causes the
out-of-sequence times that OLC seems objects to.

There are two workarounds and you can use either or both.

1. Set the logging interval to 4 seconds or more, which will conceal the
2-second jump.

2. As you said, Switch on well in advance. 15 minutes is about right IMHO.
10 minutes is the time it takes to be assured that the time is correct, and
5 more to be sure that the FR has not back-logged the jump.

Dan Marotta

May 26th 19, 04:56 PM

I tried to change either the logging interval or just the interval that
is downloaded after the flight but it was not intuitive after the
flight.Â* I guess a little ground study is in order.

As to the published interference testing times, I didn't check, but the
only dropouts I had were up around Las Vegas (the northeast part of the
flight).Â* Once moving south again, I did not see them again. As stated
before, I lost GPS on everything in the cockpit - all of my stuff and my
copilot's iPad, as well.Â* I'd bet on jamming.Â* I'll try to do better on
what and when next time.

On 5/26/2019 4:04 AM, Tim Newport-Peace wrote:
> At 02:38 26 May 2019, kinsell wrote:
>> On 5/25/19 6:58 PM, Dan Marotta wrote:
>>> I turned on my CN2 and CNvXC 20 minutes before engine start today. Then
>>> it was another 15 minutes to warm up the engine before take off.Ã‚Â* Even
>>> though I had several GPS drop outs during the flight, it scored
>>> perfectly.Ã‚Â* BTW, all other devices in the cockpit, including my buddy's
>>> iPad also lost GPS for those times.Ã‚Â* Looks like the work around is to
>>> let the GPSs get time synchronized before take off.
>>>
> Basically, the Time in the IGC file originates in the GPS Engine. At
> power-up it comes from the RTC, but once 'Satellite Time' has been received
> and the correct number of Leap Seconds applied, the source switches to
> that.
>
> The difference can be in the order of 2 seconds, and this causes the
> out-of-sequence times that OLC seems objects to.
>
> There are two workarounds and you can use either or both.
>
> 1. Set the logging interval to 4 seconds or more, which will conceal the
> 2-second jump.
>
> 2. As you said, Switch on well in advance. 15 minutes is about right IMHO.
> 10 minutes is the time it takes to be assured that the time is correct, and
> 5 more to be sure that the FR has not back-logged the jump.
>
>
>

--
Dan, 5J

Papa3[_2_]

May 26th 19, 05:10 PM

Adding anecdotal evidence to the startup idea... I had my first-ever "implausible time record" failure on my ClearNav two weeks ago. It was an unusual flight, as I realized after takeoff that I didn't have the right databases loaded (turnpoints and airspace) since I was flying "off the map" from our typical task area (it was a really good day). About 45 minutes into the flight I went to load the full US Airspace file, and the ClearNav locked up. I power cycled it and it cleared everything, but a few minutes after the approximate point of the power cycle I got the implausible time record. I did get another one later in the flight as well, but all flights before and since have been fine.

P3

Tim Newport-Peace[_6_]

May 26th 19, 10:58 PM

At 15:56 26 May 2019, Dan Marotta wrote:

>As to the published interference testing times, I didn't check, but the
>only dropouts I had were up around Las Vegas (the northeast part of the
>flight).Â* Once moving south again, I did not see them again. As stated
>before, I lost GPS on everything in the cockpit - all of my stuff and my
>copilot's iPad, as well.Â* I'd bet on jamming.Â* I'll try to do better on

>what and when next time.
>
Interestingly, in your flight 2019-05-04-CNI-V8Q-01, not only were there
lots of loss of 3D logging (dropouts), but around 22:23:09 (UTC) the GPS
altitude rose to an amazing 163,215 feet (Eat you heart out Perlan).

Dan Marotta

May 27th 19, 01:59 AM

Yaas...Â* My cannula was working over time!

On 5/26/2019 3:58 PM, Tim Newport-Peace wrote:
> At 15:56 26 May 2019, Dan Marotta wrote:
>
>> As to the published interference testing times, I didn't check, but the
>> only dropouts I had were up around Las Vegas (the northeast part of the
>> flight).Ã‚Â* Once moving south again, I did not see them again. As stated
>> before, I lost GPS on everything in the cockpit - all of my stuff and my
>> copilot's iPad, as well.Ã‚Â* I'd bet on jamming.Ã‚Â* I'll try to do better on
>> what and when next time.
>>
> Interestingly, in your flight 2019-05-04-CNI-V8Q-01, not only were there
> lots of loss of 3D logging (dropouts), but around 22:23:09 (UTC) the GPS
> altitude rose to an amazing 163,215 feet (Eat you heart out Perlan).
>
>
>

--
Dan, 5J

kinsell

May 27th 19, 03:07 AM

Sure would be nice if the gps engines could filter out the worst of
this. 16K to 0 or 160K in a second seems rather umm implausible.

If it is jamming, as it sounds like, expect it to get nothing but worse.

On 5/26/19 9:56 AM, Dan Marotta wrote:
> I tried to change either the logging interval or just the interval that
> is downloaded after the flight but it was not intuitive after the
> flight.Â* I guess a little ground study is in order.
>
> As to the published interference testing times, I didn't check, but the
> only dropouts I had were up around Las Vegas (the northeast part of the
> flight).Â* Once moving south again, I did not see them again. As stated
> before, I lost GPS on everything in the cockpit - all of my stuff and my
> copilot's iPad, as well.Â* I'd bet on jamming.Â* I'll try to do better on
> what and when next time.
>
> On 5/26/2019 4:04 AM, Tim Newport-Peace wrote:
>> At 02:38 26 May 2019, kinsell wrote:
>>> On 5/25/19 6:58 PM, Dan Marotta wrote:
>>>> I turned on my CN2 and CNvXC 20 minutes before engine start today. Then
>>>> it was another 15 minutes to warm up the engine before take off.Ã‚Â* Even
>>>> though I had several GPS drop outs during the flight, it scored
>>>> perfectly.Ã‚Â* BTW, all other devices in the cockpit, including my
>>>> buddy's
>>>> iPad also lost GPS for those times.Ã‚Â* Looks like the work around is to
>>>> let the GPSs get time synchronized before take off.
>>>>
>> Basically, the Time in the IGC file originates in the GPS Engine. At
>> power-up it comes from the RTC, but once 'Satellite Time' has been
>> received
>> and the correct number of Leap Seconds applied, the source switches to
>> that.
>>
>> The difference can be in the order of 2 seconds, and this causes the
>> out-of-sequence times that OLC seems objects to.
>>
>> There are two workarounds and you can use either or both.
>>
>> 1. Set the logging interval to 4 seconds or more, which will conceal the
>> 2-second jump.
>>
>> 2. As you said, Switch on well in advance. 15 minutes is about right
>> IMHO.
>> 10 minutes is the time it takes to be assured that the time is
>> correct, and
>> 5 more to be sure that the FR has not back-logged the jump.
>>
>>
>>
>

Dan Marotta

May 27th 19, 04:44 PM

The FAA wants to be notified if loss of GPS guidance affects flight
safety.Â* I have heard reports from airliners over New Mexico that have
lost GPS.Â* The FAA can issue an order to the military to stop the
jamming if flight safety is an issue.Â* I've also lost my IFR certified
WAAS GPS/ADS-B in the C-180.Â* I reported it to ABQ Center and they asked
if I needed assistance.Â* Flying between mountain ranges with 100+ mile
visibility, I could pretty much see my destination.Â* It's the same in
gliding with the only problem being corrupt igc files.

On 5/26/2019 8:07 PM, kinsell wrote:
> Sure would be nice if the gps engines could filter out the worst of
> this.Â* 16K to 0 or 160K in a second seems ratherÂ* umm implausible.
>
> If it is jamming, as it sounds like, expect it to get nothing but worse.
>
>
> On 5/26/19 9:56 AM, Dan Marotta wrote:
>> I tried to change either the logging interval or just the interval
>> that is downloaded after the flight but it was not intuitive after
>> the flight.Â* I guess a little ground study is in order.
>>
>> As to the published interference testing times, I didn't check, but
>> the only dropouts I had were up around Las Vegas (the northeast part
>> of the flight).Â* Once moving south again, I did not see them again.
>> As stated before, I lost GPS on everything in the cockpit - all of my
>> stuff and my copilot's iPad, as well.Â* I'd bet on jamming.Â* I'll try
>> to do better on what and when next time.
>>
>> On 5/26/2019 4:04 AM, Tim Newport-Peace wrote:
>>> At 02:38 26 May 2019, kinsell wrote:
>>>> On 5/25/19 6:58 PM, Dan Marotta wrote:
>>>>> I turned on my CN2 and CNvXC 20 minutes before engine start today.
>>>>> Then
>>>>> it was another 15 minutes to warm up the engine before take off.Ã‚Â*
>>>>> Even
>>>>> though I had several GPS drop outs during the flight, it scored
>>>>> perfectly.Ã‚Â* BTW, all other devices in the cockpit, including my
>>>>> buddy's
>>>>> iPad also lost GPS for those times.Ã‚Â* Looks like the work around
>>>>> is to
>>>>> let the GPSs get time synchronized before take off.
>>>>>
>>> Basically, the Time in the IGC file originates in the GPS Engine. At
>>> power-up it comes from the RTC, but once 'Satellite Time' has been
>>> received
>>> and the correct number of Leap Seconds applied, the source switches to
>>> that.
>>>
>>> The difference can be in the order of 2 seconds, and this causes the
>>> out-of-sequence times that OLC seems objects to.
>>>
>>> There are two workarounds and you can use either or both.
>>>
>>> 1. Set the logging interval to 4 seconds or more, which will conceal
>>> the
>>> 2-second jump.
>>>
>>> 2. As you said, Switch on well in advance. 15 minutes is about right
>>> IMHO.
>>> 10 minutes is the time it takes to be assured that the time is
>>> correct, and
>>> 5 more to be sure that the FR has not back-logged the jump.
>>>
>>>
>>>
>>
>

--
Dan, 5J

Tango Eight

May 28th 19, 04:48 PM

How to change the igc flight log time interval on CN2:
https://youtu.be/AkJwwCbGMZQ

CN2 stores logs internally at 1 second. You can d/l to USB at 1, 2, 4 or 10 second intervals.

Please pay close attention to the voice over. There is one especially non-obvious press of the down arrow key.

We think that d/l at 4 second interval solves (really: masks) the discontinuity that occurs when the UTC - GPS time offset update is received from the GPS system.

best regards,
Evan Ludeman for CNi

Dan Marotta

May 28th 19, 05:57 PM

Thanks, Evan.

I figured it out at home using the CN2 simulator.

On 5/28/2019 9:48 AM, Tango Eight wrote:
> How to change the igc flight log time interval on CN2:
> https://youtu.be/AkJwwCbGMZQ
>
> CN2 stores logs internally at 1 second. You can d/l to USB at 1, 2, 4 or 10 second intervals.
>
> Please pay close attention to the voice over. There is one especially non-obvious press of the down arrow key.
>
> We think that d/l at 4 second interval solves (really: masks) the discontinuity that occurs when the UTC - GPS time offset update is received from the GPS system.
>
> best regards,
> Evan Ludeman for CNi

--
Dan, 5J

[email protected][_2_]

May 30th 19, 01:01 PM

Well, here I am in Cordele with R5S starting on Monday and got the OLC time error message after submitting my ClearNav II log for yesterdayâ€™s flight.
So, downloaded CN vario version and got the same error message. For thrills I loaded a flight on 5/15/19 and although OLC advised late, accepted the flight into the system. I have changed nothing nor updated either unit since 5/15 so why then, not now?
I will look at and change the interval to 4 secs and try again ( as mentioned by T8 in this thread).
Questions and request...
Will I have issues with scoring during the contest (winscore)?
I would appreciate if someone would post an update summary of do and donâ€™t and ideas in a simple to grasp way that even an airline pilot might follow.
Many thanks.
R

kinsell

May 30th 19, 01:44 PM

On 5/30/19 6:01 AM, wrote:
> Well, here I am in Cordele with R5S starting on Monday and got the OLC time error message after submitting my ClearNav II log for yesterdayâ€™s flight.
> So, downloaded CN vario version and got the same error message. For thrills I loaded a flight on 5/15/19 and although OLC advised late, accepted the flight into the system. I have changed nothing nor updated either unit since 5/15 so why then, not now?

It's likely OLC just recently added the check for bad time records.

> I will look at and change the interval to 4 secs and try again ( as mentioned by T8 in this thread).

That should work. You have 48 hrs after flight ended to delete bad data
and try again.

> Questions and request...
> Will I have issues with scoring during the contest (winscore)?

It's highly unlikely a program like Winscore would have have problems,
even if you turn in a log with a glitch. No reason to turn in a log
with the glitch.

> I would appreciate if someone would post an update summary of do and donâ€™t and ideas in a simple to grasp way that even an airline pilot might follow.

You can either download with the 4 second intervals, or you can turn on
your loggers early. I would wait until you get a 3D lock indication,
then add ten minutes before takeoff. You can do both if you want.

Dave

> Many thanks.
> R
>

Tango Eight

May 30th 19, 01:46 PM

Hi Henry,

There will be no issue with Winscore.

What's going on here:

1. UTC and GPS time are not the same. The current offset is 18 seconds.

2. When the GPS starts up, it starts with an offset programmed in firmware.. This offset is less than 18 seconds.

3. After GPS lock, the GPS receiver gets the current offset from the system, typically about 5 minutes after GPS lock. It applies the new offset immediately, and the jump causes one out of sequence B record if the flight recorder is recording. It doesn't start recording until you are flying.

4. OLC picks up the out of sequence B record if it exists.

Since the offset change is 2 or 3 seconds, it can be masked by setting the igc file fix interval to 4 seconds. You can avoid the jump altogether by powering up > 5 minutes before flying.

If you get a bad OLC result, you can fix it by downloading your flight again at either 4 or 10 second interval and resubmitting.

best regards,
Evan Ludeman

On Thursday, May 30, 2019 at 8:01:58 AM UTC-4, wrote:
> Well, here I am in Cordele with R5S starting on Monday and got the OLC time error message after submitting my ClearNav II log for yesterdayâ€™s flight.
> So, downloaded CN vario version and got the same error message. For thrills I loaded a flight on 5/15/19 and although OLC advised late, accepted the flight into the system. I have changed nothing nor updated either unit since 5/15 so why then, not now?
> I will look at and change the interval to 4 secs and try again ( as mentioned by T8 in this thread).
> Questions and request...
> Will I have issues with scoring during the contest (winscore)?
> I would appreciate if someone would post an update summary of do and donâ€™t and ideas in a simple to grasp way that even an airline pilot might follow.
> Many thanks.
> R

[email protected][_2_]

May 30th 19, 02:46 PM

Thanks to the brain trust for the easy to understand summary.....the sport has improved due to the smart guys.
I will save and pass on to others.
Great flights!

R

Dan Marotta

May 30th 19, 03:45 PM

I've made two flights since experiencing the problem.Â* Since then, I've
turned on my CN devices 20 or so minutes before takeoff and have not
seen a repeat of the problem.

On 5/30/2019 6:46 AM, Tango Eight wrote:
> Hi Henry,
>
> There will be no issue with Winscore.
>
> What's going on here:
>
> 1. UTC and GPS time are not the same. The current offset is 18 seconds.
>
> 2. When the GPS starts up, it starts with an offset programmed in firmware. This offset is less than 18 seconds.
>
> 3. After GPS lock, the GPS receiver gets the current offset from the system, typically about 5 minutes after GPS lock. It applies the new offset immediately, and the jump causes one out of sequence B record if the flight recorder is recording. It doesn't start recording until you are flying.
>
> 4. OLC picks up the out of sequence B record if it exists.
>
> Since the offset change is 2 or 3 seconds, it can be masked by setting the igc file fix interval to 4 seconds. You can avoid the jump altogether by powering up > 5 minutes before flying.
>
> If you get a bad OLC result, you can fix it by downloading your flight again at either 4 or 10 second interval and resubmitting.
>
> best regards,
> Evan Ludeman
>
>
> On Thursday, May 30, 2019 at 8:01:58 AM UTC-4, wrote:
>> Well, here I am in Cordele with R5S starting on Monday and got the OLC time error message after submitting my ClearNav II log for yesterdayâ€™s flight.
>> So, downloaded CN vario version and got the same error message. For thrills I loaded a flight on 5/15/19 and although OLC advised late, accepted the flight into the system. I have changed nothing nor updated either unit since 5/15 so why then, not now?
>> I will look at and change the interval to 4 secs and try again ( as mentioned by T8 in this thread).
>> Questions and request...
>> Will I have issues with scoring during the contest (winscore)?
>> I would appreciate if someone would post an update summary of do and donâ€™t and ideas in a simple to grasp way that even an airline pilot might follow.
>> Many thanks.
>> R

--
Dan, 5J

Tom Kelley #711

May 30th 19, 07:33 PM

On Thursday, May 30, 2019 at 8:45:43 AM UTC-6, Dan Marotta wrote:
> I've made two flights since experiencing the problem.Â* Since then, I've
> turned on my CN devices 20 or so minutes before takeoff and have not
> seen a repeat of the problem.
>
> On 5/30/2019 6:46 AM, Tango Eight wrote:
> > Hi Henry,
> >
> > There will be no issue with Winscore.
> >
> > What's going on here:
> >
> > 1. UTC and GPS time are not the same. The current offset is 18 seconds.
> >
> > 2. When the GPS starts up, it starts with an offset programmed in firmware. This offset is less than 18 seconds.
> >
> > 3. After GPS lock, the GPS receiver gets the current offset from the system, typically about 5 minutes after GPS lock. It applies the new offset immediately, and the jump causes one out of sequence B record if the flight recorder is recording. It doesn't start recording until you are flying.
> >
> > 4. OLC picks up the out of sequence B record if it exists.
> >
> > Since the offset change is 2 or 3 seconds, it can be masked by setting the igc file fix interval to 4 seconds. You can avoid the jump altogether by powering up > 5 minutes before flying.
> >
> > If you get a bad OLC result, you can fix it by downloading your flight again at either 4 or 10 second interval and resubmitting.
> >
> > best regards,
> > Evan Ludeman
> >
> >
> > On Thursday, May 30, 2019 at 8:01:58 AM UTC-4, wrote:
> >> Well, here I am in Cordele with R5S starting on Monday and got the OLC time error message after submitting my ClearNav II log for yesterdayâ€™s flight.
> >> So, downloaded CN vario version and got the same error message. For thrills I loaded a flight on 5/15/19 and although OLC advised late, accepted the flight into the system. I have changed nothing nor updated either unit since 5/15 so why then, not now?
> >> I will look at and change the interval to 4 secs and try again ( as mentioned by T8 in this thread).
> >> Questions and request...
> >> Will I have issues with scoring during the contest (winscore)?
> >> I would appreciate if someone would post an update summary of do and donâ€™t and ideas in a simple to grasp way that even an airline pilot might follow.
> >> Many thanks.
> >> R
>
> --
> Dan, 5J

I sent T8 an update yesterday on my XC logger. I had it on 2 secs and changed to 4 secs and turned it on 12 minutes prior to launch. All problems have now gone on the OLC.
Best. #711.