GPS Nav question ....

I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. Wondering what I should try or look for.

- Unit is mounted on the shelf behind the pilot in a ASW-20
- nothing covering it
- Camelback bladder placed next to it
- Unit was re-calibrated last year
- new internal battery installed last year
- hardware version 38
- software version 5.1
- Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- glider battery was reading 12.8 volts at time of lost reception.
- SeeYou would not download file from the device, it hung up
- Cambridge Aero Explorer Plus was able to down load the file just
fine

The only thing different in the cockpit was that I mounted my SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

On 8/14/11 12:12 PM, Ron Gleason wrote:
I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. Wondering what I should try or look for.

- Unit is mounted on the shelf behind the pilot in a ASW-20
- nothing covering it
- Camelback bladder placed next to it
- Unit was re-calibrated last year
- new internal battery installed last year
- hardware version 38
- software version 5.1
- Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- glider battery was reading 12.8 volts at time of lost reception.
- SeeYou would not download file from the device, it hung up
- Cambridge Aero Explorer Plus was able to down load the file just
fine

The only thing different in the cockpit was that I mounted my SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

Ron

When you say you lost reception just top clarify the L-NAV stopped
getting data in flight (and still now?) but the GPS-NAV has logged a CAI
file that is OK, you can download that file and it does not have data
gaps when you look at it in SeeYou or similar? and the file also passes
security tests?

If that is correct then my assumption would be the most likely problem
is just cabling between the L-NAV and GPS-NAV. If you exclude that then
you have a faulty GPS-NAV or L-NAV and swapping devices with somebody
else would be an easy way to test for that.

It is not uncommon with these boxes to have problems with wiring. These
devices are getting pretty old and possible issues including corrosion
broken pins or over-bent pins (esp. on telco jacks=sockets), and loose
pins or just broken wires in the plugs . Have a really good look at all
pins and connectors in the box and on the cable. If the cables are
suspect install new connectors and/or replace the cable.

Darryl

On Aug 14, 2:53*pm, Darryl Ramm wrote:
On 8/14/11 12:12 PM, Ron Gleason wrote:









I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. *Wondering what I should try or look for.

- *Unit is mounted on the shelf behind the pilot in a ASW-20
- *nothing covering it
- *Camelback bladder placed next to it
- *Unit was re-calibrated last year
- *new internal battery installed last year
- *hardware version 38
- *software version 5.1
- *Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- *glider battery was reading 12.8 volts at time of lost reception.
- *SeeYou would not download file from the device, it hung up
- *Cambridge Aero Explorer Plus was able to down load the file just
fine

The only thing different in the cockpit was that I mounted my SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

Ron

When you say you lost reception just top clarify the L-NAV stopped
getting data in flight (and still now?) but the GPS-NAV has logged a CAI
file that is OK, you can download that file and it does not have data
gaps when you look at it in SeeYou or similar? and the file also passes
security tests?

If that is correct then my assumption would be the most likely problem
is just cabling between the L-NAV and GPS-NAV. If you exclude that then
you have a faulty GPS-NAV or L-NAV and swapping devices with somebody
else would be an easy way to test for that.

It is not uncommon with these boxes to have problems with wiring. These
devices are getting pretty old and possible issues including corrosion
broken pins or over-bent pins (esp. on telco jacks=sockets), and loose
pins or just broken wires in the plugs . Have a really good look at all
pins and connectors in the box and on the cable. If the cables are
suspect install new connectors and/or replace the cable.

Darryl

To clarify, the GPS NAV display stopped display values in data
fields. I tried a different TP and GO and still no data

The L-NAV displayed the message WAITING GPS or GPS WAITING

The CAI file stopped at the point in the flight where the GPS NAV data
fields disappeared.

The Oudie, stand alone, recorded the complete flight.

I have visually checked some of the wiring but will get the volt meter
or try it again next flight to see if it repeats.

Ron

On 8/14/11 2:57 PM, Ron Gleason wrote:
On Aug 14, 2:53 pm, Darryl wrote:
On 8/14/11 12:12 PM, Ron Gleason wrote:









I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. Wondering what I should try or look for.

- Unit is mounted on the shelf behind the pilot in a ASW-20
- nothing covering it
- Camelback bladder placed next to it
- Unit was re-calibrated last year
- new internal battery installed last year
- hardware version 38
- software version 5.1
- Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- glider battery was reading 12.8 volts at time of lost reception.
- SeeYou would not download file from the device, it hung up
- Cambridge Aero Explorer Plus was able to down load the file just
fine

The only thing different in the cockpit was that I mounted my SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

Ron

When you say you lost reception just top clarify the L-NAV stopped
getting data in flight (and still now?) but the GPS-NAV has logged a CAI
file that is OK, you can download that file and it does not have data
gaps when you look at it in SeeYou or similar? and the file also passes
security tests?

If that is correct then my assumption would be the most likely problem
is just cabling between the L-NAV and GPS-NAV. If you exclude that then
you have a faulty GPS-NAV or L-NAV and swapping devices with somebody
else would be an easy way to test for that.

It is not uncommon with these boxes to have problems with wiring. These
devices are getting pretty old and possible issues including corrosion
broken pins or over-bent pins (esp. on telco jacks=sockets), and loose
pins or just broken wires in the plugs . Have a really good look at all
pins and connectors in the box and on the cable. If the cables are
suspect install new connectors and/or replace the cable.

Darryl

To clarify, the GPS NAV display stopped display values in data
fields. I tried a different TP and GO and still no data

The L-NAV displayed the message WAITING GPS or GPS WAITING

The CAI file stopped at the point in the flight where the GPS NAV data
fields disappeared.

The Oudie, stand alone, recorded the complete flight.

I have visually checked some of the wiring but will get the volt meter
or try it again next flight to see if it repeats.

Ron

Those modular telco connectors are especially suspect. I've had to both
(carefully) bend back up pins in a Model 25 socket so they made better
contact and cut off and replace the crimp on cable connectors. Sometimes
very subtle things happen with those, like the wire breaks inside or
just at the connector and it becomes intermittent. Try carefully flexing
the wires and pulling and pushing on them as you check with a multi-meter.

The GPS-NAV GPS status LED is a good clue. Is it illuminated at all?
Solid green (trying to get a fix) or blinking (has a fix, then something
downstream in the wiring or the rest of the GPS-NAV or LNAV is faulty).

Darryl

On Aug 14, 4:20*pm, Darryl Ramm wrote:
On 8/14/11 2:57 PM, Ron Gleason wrote:









On Aug 14, 2:53 pm, Darryl *wrote:
On 8/14/11 12:12 PM, Ron Gleason wrote:

I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. *Wondering what I should try or look for.

- *Unit is mounted on the shelf behind the pilot in a ASW-20
- *nothing covering it
- *Camelback bladder placed next to it
- *Unit was re-calibrated last year
- *new internal battery installed last year
- *hardware version 38
- *software version 5.1
- *Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- *glider battery was reading 12.8 volts at time of lost reception.
- *SeeYou would not download file from the device, it hung up
- *Cambridge Aero Explorer Plus was able to down load the file just
fine

The only thing different in the cockpit was that I mounted my SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

Ron

When you say you lost reception just top clarify the L-NAV stopped
getting data in flight (and still now?) but the GPS-NAV has logged a CAI
file that is OK, you can download that file and it does not have data
gaps when you look at it in SeeYou or similar? and the file also passes
security tests?

If that is correct then my assumption would be the most likely problem
is just cabling between the L-NAV and GPS-NAV. If you exclude that then
you have a faulty GPS-NAV or L-NAV and swapping devices with somebody
else would be an easy way to test for that.

It is not uncommon with these boxes to have problems with wiring. These
devices are getting pretty old and possible issues including corrosion
broken pins or over-bent pins (esp. on telco jacks=sockets), and loose
pins or just broken wires in the plugs . Have a really good look at all
pins and connectors in the box and on the cable. If the cables are
suspect install new connectors and/or replace the cable.

Darryl

To clarify, the GPS NAV display stopped display values in data
fields. *I tried a different TP and GO and still no data

The L-NAV displayed the message WAITING GPS or GPS WAITING

The CAI file stopped at the point in the flight where the GPS NAV data
fields disappeared.

The Oudie, stand alone, recorded the complete flight.

I have visually checked some of the wiring but will get the volt meter
or try it again next flight to see if it repeats.

Ron

Those modular telco connectors are especially suspect. I've had to both
(carefully) bend back up pins in a Model 25 socket so they made better
contact and cut off and replace the crimp on cable connectors. Sometimes
very subtle things happen with those, like the wire breaks inside or
just at the connector and it becomes intermittent. Try carefully flexing
the wires and pulling and pushing on them as you check with a multi-meter..

The GPS-NAV GPS status LED is a good clue. Is it illuminated at all?
Solid green (trying to get a fix) or blinking (has a fix, then something
downstream in the wiring or the rest of the GPS-NAV or LNAV is faulty).

Darryl

Just brought it outside and plugged it, external power not in the
glider. Green light appeared and it started blinking a few minutes
later. Will be checking the connection to the display and L-NAV next.

Thanks for the hints and advice

On Aug 14, 4:32*pm, Ron Gleason wrote:
On Aug 14, 4:20*pm, Darryl Ramm wrote:





On 8/14/11 2:57 PM, Ron Gleason wrote:

On Aug 14, 2:53 pm, Darryl *wrote:
On 8/14/11 12:12 PM, Ron Gleason wrote:

I have been using a GPS Nav and L-Nav combination for a year or so, it
came with the glider I procured.

Yesterday I lost GPS reception from GPS Nav, first time this has
occurred. *Wondering what I should try or look for.

- *Unit is mounted on the shelf behind the pilot in a ASW-20
- *nothing covering it
- *Camelback bladder placed next to it
- *Unit was re-calibrated last year
- *new internal battery installed last year
- *hardware version 38
- *software version 5.1
- *Cambridge Aero explorer plus says voltage of internal battery 3.0
volts
- *glider battery was reading 12.8 volts at time of lost reception.

Alittle off topic but thinking about mounting my Powerflare brick and
trying to keep GPS antenna away from each other, I was going to move one of
the antenna I have on the side of my glare sheild to the turtle deck and
velcro it to the top of the GFRP turtledeck in my Ventus B. Reading the
info about flarm antenna should not be installled "touching" the canopy
would or should this be a problem with normal GPS antenna?


The only thing different in the cockpit was that I mounted my
SPOT
device on my left parachute strap around chest height.

I do not see any parameters that allow me to reset the logger or
delete logs from it.

Any ideas or thoughts?

Ron Gleason

Ron

When you say you lost reception just top clarify the L-NAV stopped
getting data in flight (and still now?) but the GPS-NAV has logged
a=

CH Ventus B

"If we are all "just dust in the wind", then I want to be at the top of a Huge Dust Devil!"

On 8/15/11 9:20 AM, Cliff Hilty wrote:
Alittle off topic but thinking about mounting my Powerflare brick and
trying to keep GPS antenna away from each other, I was going to move one of
the antenna I have on the side of my glare sheild to the turtle deck and
velcro it to the top of the GFRP turtledeck in my Ventus B. Reading the
info about flarm antenna should not be installled "touching" the canopy
would or should this be a problem with normal GPS antenna?

Well that's what starting a new thread is for, I changed the topic.

Again the real concern (if any in practice) is unlikely to be "keeping
GPS antennas away from each other" it is more likely keeping GPS
antennas away from the FLARM transmitter antenna.

The concern with the FLARM vertical antennas touching or intermittently
touching the canopy is static electricity discharge. That requires the
canopy to charge to a significant level beyond the rest of the
fuselage--I would expect the PowerFLARM box and its antenna should be
sitting at that fuselage potential via ground wires and fuselage/panel
contact. It seems unlikely but I guess it is possible.

Having an antenna touch the fuselage under the turtledeck should not be
a problem and there are gliders with antennas mounted like this today.
Make sure it is not covered by carbon fiber. When attaching anything to
the main fuselage itself like under the turtle deck the static potential
should all be the same (the electrical system is going to be effectively
earthed at multiple places (e.g. avionics boxes mounts in the panel,
antenna ground planes, etc.)--at least as far as static electricity is
concerned.

Personally I would wait and see how the PowerFLARM works before doing or
even planning surgery moving things around--with the obvious exception
if the PowerFLARM box now is going to cover/obscure the sky view of your
current GPS antenna. There is a trade-off in running long remote GPS
antenna. Many installs like being discussed will have over 10' of coax
to the antenna and maybe 6dB or more of signal loss added to the GPS
signal. While these active (i.e. they have an amplifier in the antenna
powered by DC from the cable) GPS antennas tolerate longer cables
surprisingly well just be careful going crazy with long cables, and
avoid multiple connectors etc. e.g it may be better to get a custom made
longer single piece cable if possible. Also different GPS antennas have
different amp gains and some vendors tout their antennas higher gain, if
you do run a long cable and especially if using an older GPS antenna and
have problems then it may be worth trying a higher gain antenna.

Darryl

On Aug 15, 2:34*pm, Darryl Ramm wrote:
On 8/15/11 9:20 AM, Cliff Hilty wrote:

Alittle off topic but thinking about mounting my Powerflare brick and
trying to keep GPS antenna away from each other, I was going to move one of
the antenna I have on the side of my glare sheild to the turtle deck and
velcro it to the top of the GFRP turtledeck in my Ventus B. Reading the
info about flarm antenna should not be installled "touching" the canopy
would or should this be a problem with normal GPS antenna?

Well that's what starting a new thread is for, I changed the topic.

Again the real concern (if any in practice) is unlikely to be "keeping
GPS antennas away from each other" it is more likely keeping GPS
antennas away from the FLARM transmitter antenna.

The concern with the FLARM vertical antennas touching or intermittently
touching the canopy is static electricity discharge. That requires the
canopy to charge to a significant level beyond the rest of the
fuselage--I would expect the PowerFLARM box and its antenna should be
sitting at that fuselage potential via ground wires and fuselage/panel
contact. It seems unlikely but I guess it is possible.

Having an antenna touch the fuselage under the turtledeck should not be
a problem and there are gliders with antennas mounted like this today.
Make sure it is not covered by carbon fiber. When attaching anything to
the main fuselage itself like under the turtle deck the static potential
should all be the same (the electrical system is going to be effectively
* earthed at multiple places (e.g. avionics boxes mounts in the panel,
antenna ground planes, etc.)--at least as far as static electricity is
concerned.

Personally I would wait and see how the PowerFLARM works before doing or
even planning surgery moving things around--with the obvious exception
if the PowerFLARM box now is going to cover/obscure the sky view of your
current GPS antenna. There is a trade-off in running long remote GPS
antenna. Many installs like being discussed will have over 10' of coax
to the antenna and maybe 6dB or more of signal loss added to the GPS
signal. While these active (i.e. they have an amplifier in the antenna
powered by DC from the cable) GPS antennas tolerate longer cables
surprisingly well just be careful going crazy with long cables, and
avoid multiple connectors etc. e.g it may be better to get a custom made
longer single piece cable if possible. Also different GPS antennas have
different amp gains and some vendors tout their antennas higher gain, if
you do run a long cable and especially if using an older GPS antenna and
have problems then it may be worth trying a higher gain antenna.

Darryl

I'll jump in at something of a tangent. Is anyone carrying the FLARM
antennas in the US yet? The annual on my plane is coming up and I'd
like to run the cables under the seat pan while I have the thing
apart,
and not have to pull it all out again a few months later when I
install
my brick.

-- Matt

At 19:43 15 August 2011, mattm wrote:
On Aug 15, 2:34=A0pm, Darryl Ramm wrote:
On 8/15/11 9:20 AM, Cliff Hilty wrote:

Alittle off topic but thinking about mounting my Powerflare brick and
trying to keep GPS antenna away from each other, I was going to move
on=
e of
the antenna I have on the side of my glare sheild to the turtle deck
an=
d
velcro it to the top of the GFRP turtledeck in my Ventus B. Reading
the
info about flarm antenna should not be installled "touching" the
canopy
would or should this be a problem with normal GPS antenna?

Well that's what starting a new thread is for, I changed the topic.

Again the real concern (if any in practice) is unlikely to be "keeping
GPS antennas away from each other" it is more likely keeping GPS
antennas away from the FLARM transmitter antenna.

The concern with the FLARM vertical antennas touching or intermittently
touching the canopy is static electricity discharge. That requires the
canopy to charge to a significant level beyond the rest of the
fuselage--I would expect the PowerFLARM box and its antenna should be
sitting at that fuselage potential via ground wires and fuselage/panel
contact. It seems unlikely but I guess it is possible.

Having an antenna touch the fuselage under the turtledeck should not be
a problem and there are gliders with antennas mounted like this today.
Make sure it is not covered by carbon fiber. When attaching anything to
the main fuselage itself like under the turtle deck the static
potential
should all be the same (the electrical system is going to be
effectively
=A0 earthed at multiple places (e.g. avionics boxes mounts in the
panel,
antenna ground planes, etc.)--at least as far as static electricity is
concerned.

Personally I would wait and see how the PowerFLARM works before doing
or
even planning surgery moving things around--with the obvious exception
if the PowerFLARM box now is going to cover/obscure the sky view of
your
current GPS antenna. There is a trade-off in running long remote GPS
antenna. Many installs like being discussed will have over 10' of coax
to the antenna and maybe 6dB or more of signal loss added to the GPS
signal. While these active (i.e. they have an amplifier in the antenna
powered by DC from the cable) GPS antennas tolerate longer cables
surprisingly well just be careful going crazy with long cables, and
avoid multiple connectors etc. e.g it may be better to get a custom
made
longer single piece cable if possible. Also different GPS antennas have
different amp gains and some vendors tout their antennas higher gain,
if
you do run a long cable and especially if using an older GPS antenna
and
have problems then it may be worth trying a higher gain antenna.

Darryl

I'll jump in at something of a tangent. Is anyone carrying the FLARM
antennas in the US yet? The annual on my plane is coming up and I'd
like to run the cables under the seat pan while I have the thing
apart,
and not have to pull it all out again a few months later when I
install
my brick.

-- Matt


That's kinda my take, if the units (brick) arn't going to be here until
after this year, I would like to be ready as well. Now I was assuming the
the brick remote face is what would house the antenna and putting that up
on my glare sheild or somewhere close (side to side) would put the antenna
within 1 foot of both of my other GPS antenna. I had a problem with my EW
microRecorder getting a signal when I had it in the center top of my glare
shield and my Garmin 196 on the far left. I moved the ew to the far right
and that solved the problem now having to put the powerflarm somewhere I am
trying to do preventative maintenance/install ideas. The ew comes with
about a 6 foot cable and it would be easiest to move it to the turtle deck
since that is where I put the unit anyway and now am running the antenna to
the front. I like matt's idea of putting it under the seat pan though and
might consider that if you can remotely mount the flarm antenna.


CH Ventus B

"If we are all "just dust in the wind", then I want to be at the top of a Huge Dust Devil!"