Flarm reporting my own ADSB Out

Greetings,

Installed my new Trig and TN72 and today when I powered up both my Flarm and the Trig, the Flarmview reported my own ADSB Out signal as a ADSB target.

PowerFlarm Core - 6.42 Firmware
Flarmview - 2.39 Firmware

Flarm Config ID shows identical to ADSB Out ID

FlarmView is showing my target as my contest number so it's correctly matching my ADSB Out ID to my contest number based on current FlarmNet.

Flarmview shows correct Flarm ID when Flarm - Configuration is selected.


Am I missing something? Is this a PowerFlarm issue or a FlarmView issue? I was expecting that the Flarm/FlarmView would ignore my own signal based on the ID.

All of this was stationary on the ground testing, but I doubt that it would be different if I was flying.

Thanks for any help or advice.

Mark

On Saturday, March 10, 2018 at 9:29:57 PM UTC-5, wrote:
Greetings,

Installed my new Trig and TN72 and today when I powered up both my Flarm and the Trig, the Flarmview reported my own ADSB Out signal as a ADSB target.

PowerFlarm Core - 6.42 Firmware
Flarmview - 2.39 Firmware

Flarm Config ID shows identical to ADSB Out ID

FlarmView is showing my target as my contest number so it's correctly matching my ADSB Out ID to my contest number based on current FlarmNet.

Flarmview shows correct Flarm ID when Flarm - Configuration is selected.


Am I missing something? Is this a PowerFlarm issue or a FlarmView issue? I was expecting that the Flarm/FlarmView would ignore my own signal based on the ID.

All of this was stationary on the ground testing, but I doubt that it would be different if I was flying.

Thanks for any help or advice.

Mark

Hi Mark - here are some settings you may wish to look at in your flarmcfg.txt file:

################################################## ######################
# transponder and PCAS configuration
################################################## ######################

# do Mode C signal processing, ie, PCAS mode (0=no, 1=yes)
$PFLAC,S,MODEC,1

# own Mode C signal filtering (to eliminate your own xpdr)
# 0=aggressive (use w/ Mode C Xpdr), 1=normal (no Xpdr or Mode S)
# normal sometimes results in false PCAS alerts about every 10 min
$PFLAC,S,OWNMODEC,1

# PCAS antenna gain (30=default, higher makes PCAS targets closer)
$PFLAC,S,PCASCALIBRATION,30

# transponder type (0=None, 1=Mode C, 2=Mode S)
$PFLAC,S,XPDR,2

# use Mode S barometric altitude for PCAS height calc (0=no, 1=yes)
$PFLAC,S,MODESALT,1

Cheers
Dan

Dan,

Thanks! I had not updated the config file to show that I now had the Mode S installed. It’s now working properly.

Mark

On Sunday, March 11, 2018 at 8:39:05 AM UTC-4, wrote:
Dan,

Thanks! I had not updated the config file to show that I now had the Mode S installed. It’s now working properly.

Mark

No problem, Mark. Glad you have FLARM and glad that it is working.

Why not use 0=aggressive?

I occasionally see PCAS targets at 0 altitude differential right on top
of me.Â* I assume that's my own ship, but it's very disconcerting to have
that pop up.Â* I'll have to check my config file...

On 3/10/2018 7:46 PM, Dan Daly wrote:
# own Mode C signal filtering (to eliminate your own xpdr)
# 0=aggressive (use w/ Mode C Xpdr), 1=normal (no Xpdr or Mode S)
# normal sometimes results in false PCAS alerts about every 10 min
$PFLAC,S,OWNMODEC,1

--
Dan, 5J

On Sunday, March 11, 2018 at 8:44:54 AM UTC-7, Dan Marotta wrote:
Why not use 0=aggressive?

I occasionally see PCAS targets at 0 altitude differential right on top
of me.Â* I assume that's my own ship, but it's very disconcerting to have
that pop up.Â* I'll have to check my config file...

On 3/10/2018 7:46 PM, Dan Daly wrote:
# own Mode C signal filtering (to eliminate your own xpdr)
# 0=aggressive (use w/ Mode C Xpdr), 1=normal (no Xpdr or Mode S)
# normal sometimes results in false PCAS alerts about every 10 min
$PFLAC,S,OWNMODEC,1

--
Dan, 5J

Probably because if you have Mode S the Flarm can tell it's you, but if you have mode C all it can tell is there is some traffic nearby - perhaps you, or perhaps someone else.

I have Mode S, but I still get those occasional targets in my lap and
never see any of them...Â* Is there a Mode S filter or does Flarm think
it's smart enough not to need it?

On 3/11/2018 10:27 AM, jfitch wrote:
On Sunday, March 11, 2018 at 8:44:54 AM UTC-7, Dan Marotta wrote:
Why not use 0=aggressive?

I occasionally see PCAS targets at 0 altitude differential right on top
of me.Â* I assume that's my own ship, but it's very disconcerting to have
that pop up.Â* I'll have to check my config file...

On 3/10/2018 7:46 PM, Dan Daly wrote:
# own Mode C signal filtering (to eliminate your own xpdr)
# 0=aggressive (use w/ Mode C Xpdr), 1=normal (no Xpdr or Mode S)
# normal sometimes results in false PCAS alerts about every 10 min
$PFLAC,S,OWNMODEC,1
--
Dan, 5J
Probably because if you have Mode S the Flarm can tell it's you, but if you have mode C all it can tell is there is some traffic nearby - perhaps you, or perhaps someone else.

--
Dan, 5J

On Sunday, March 11, 2018 at 3:54:50 PM UTC-4, Dan Marotta wrote:
I have Mode S, but I still get those occasional targets in my lap and
never see any of them...Â* Is there a Mode S filter or does Flarm think
it's smart enough not to need it?

There is a Mode S filter if you set it in flarmcfg.txt.

# transponder type (0=None, 1=Mode C, 2=Mode S)
$PFLAC,S,XPDR,2

Confirm your ICAO address in the Mode S transponder and FLARM ID ($PFLAC,S,ID,XXXXXX) are the same.

They continue to work to minimize false alerts, so keeping firmware updated is advised.

Dan

I did that some time ago, but maybe a later config file left that off.Â*
Thanks for the pointer.

On 3/11/2018 2:16 PM, Dan Daly wrote:
On Sunday, March 11, 2018 at 3:54:50 PM UTC-4, Dan Marotta wrote:
I have Mode S, but I still get those occasional targets in my lap and
never see any of them...Â* Is there a Mode S filter or does Flarm think
it's smart enough not to need it?
There is a Mode S filter if you set it in flarmcfg.txt.

# transponder type (0=None, 1=Mode C, 2=Mode S)
$PFLAC,S,XPDR,2

Confirm your ICAO address in the Mode S transponder and FLARM ID ($PFLAC,S,ID,XXXXXX) are the same.

They continue to work to minimize false alerts, so keeping firmware updated is advised.

Dan

--
Dan, 5J

Question... Has anyone with a FLARM actually flown close enough to a glider that is outputting both ADS-B and FLARM and verified that only one aircraft appears on their display? The glider would have to be in range of the FLARM to ensure that both signals are hitting the front end of the FLARM.