PilotAware
British Forum => General Discussion => Topic started by: flying_john on February 13, 2016, 03:06:31 pm
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Having got the necessary cabling to connect the PAW to the TRT800, and configuring the TRT for NMEA input sentences and setting the PAW for Transponder 4800, does anyone know if there should be any icon, text or flashing light on the display of the TRT800 to show that it is sending ES messages. Or do you have to go flying and then look on FR24 ?
The PAW log shows NMEA sentences being sent, but it would be good to know whether the cabling and the USB to RS232 is all working properly, particularly as the suppliers of the recommended cable tell you to insert a config disc and configure the RS232 adaptor !
John
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Hi John
You can go to the traffic page on your nav device to see if you can see your own transponder
This was a feature put in specifically for FASVIG, to ensure the transponder settings are correct sil, sda etc
Remember to set the hexid in PAW to something other than the icao of your transponder, otherwise it will be filtered out, eg set the hexid to
FFFFFF
then you will see all non FFFFFF transponder returns
Thx
Lee
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O.k Lee thanks.
Is this feature only from certain build dates ?
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Hi John
This is available in the latest release
Thx
Lee
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John,
I'll be interested to know how you get on, not because of the PAW functionality but because of the relative location of the transponder and PAW antenna. You may need to find a friend with a second PAW a little way away to do your check for you.
There are two potential issues you may encounter:
1) Assuming your PAW antenna is inside your aircraft and your transponder antenna is on the bottom, depending on the aircraft type and the material it is made of, your own aircraft fuselage may blank the PAW reception
2) I took part in the AOPA/NATS flight trials of the LPAT (Low Power ADS-B Transceiver). Like PAW, LPAT is an ADS-B In device but it also does ADS-B Out like your TRT800 hopefully does. In flight they worked ok but did suffer from the fuselage blanking mentioned in 1) when the relative positions of antenna were not ideal. But, more importantly for your current interest was the way they worked on the ground. The two LPAT could not detect each when they were too close. There needed to be a bit of separation.
If you struggle to get your own PAW to pickup your TRT800 ADS-B Out broadcasts, see if you can find someone else with a second PAW and get them to walk away from your aircraft in line of sight. If it works like the LPAT they may need to walk 100 to 200 yards away.
Please post your results. And check your SIL, SDA, etc as Lee mentioned. You need to ensure these are correct for the MOD approvals.
These links may be helpful:
http://fasvig.org/funke-support-for-uncertified-gps-ads-b-out (http://fasvig.org/funke-support-for-uncertified-gps-ads-b-out)
http://fasvig.org/checking-ads-b-out-settings-with-pilotaware (http://fasvig.org/checking-ads-b-out-settings-with-pilotaware)
http://fasvig.org/fasvig-flies-with-lpat (http://fasvig.org/fasvig-flies-with-lpat)
Regards,
Steve
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O.K Steve thanks for the comments. I last updated about 3 weeks ago, so may have to get the latest version before I try again next weekend and I can (when under test) send the output of the txpdr into a dummy load and "sniff" off some output for the Paw 1090mhz receiver.
John
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Well, still no ES >:(
After discovering that the factory made cabling from Funke was wired incorrectly - they told us that Brown wire was Data input - I discovered they had actually wired the Brown wire to a pin marked "not used" :'(
So, I have now wired a 9 way D type to the correct pin and ground and found the TRT test mode (20) that is supposed to tell you when ES is working - Does it hell !
SO I am going to find an old lappy with RS232 port, to run a TTY "listening" session on the output of the PAw after passing through one of the myriad of USB to RS232 adaptors I have, to see if there is actually anything getting to the TRT transponder.
John
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SO I am going to find an old lappy with RS232 port, to run a TTY "listening" session on the output of the PAw after passing through one of the myriad of USB to RS232 adaptors I have, to see if there is actually anything getting to the TRT transponder.
good plan.
not sure about your transponder, but on some, they display the GPS co-ords they are receiveing in one of the setup menus ?
Thx
Lee
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Hi John
Something just sprang to mind - I also have a TRT-800.
What revision firmware is it running ?
this mentions you need 5.3,
http://docs.fasvig.info/ADS-B/Funke_TRT800A-H_Connection_uncertified_GPS.pdf
Thx
Lee
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I am fairly sure the NMEA is not getting to the Data I/P line of the Txpdr.
Can i confirm that the top right USB port (when looking at the Pi end on) is the correct USB port - or doesnt it matter.
John
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I think Ians document describes the placement, but off the top of my head
Top left 1
Bottom left 2
Top right 3
Bottom right 4
Thx
Lee
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I am fairly sure the NMEA is not getting to the Data I/P line of the Txpdr.
Can i confirm that the top right USB port (when looking at the Pi end on) is the correct USB port - or doesnt it matter.
John
Hi John
You can actually use any of the USB ports.
What is important is when you go to the paw web configure page.
You should choose the correct settings for port 3
(If you are choosing top right)
Thx
Lee
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Aha - that may be it. I dont have the unit in front of me but I do remember in the config page I have the top of the 4 config fields for serial data speeds set for the Funke transponder at 4800. If I am using the top right hand USB port it sounds as if I should be setting the 3rd field down in serial config for Funke 4800.
John
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Aha - thats what it was, I had used port 3 but configured port 1 for the Txpdr.
So it appears to work on the ground reporting my own txpdr at my position at 0feet.
Couldn't see myself on FR24, but then I was in a metal hangar with the doors shut. So next thing is a flight test when the 50hr is finished.
Do you know if you can look at FR24 or suchlike for a flight you have just made or is it only realtime flight tracking.
Thanks for everones help.
John
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Aha - thats what it was, I had used port 3 but configured port 1 for the Txpdr.
So it appears to work on the ground reporting my own txpdr at my position at 0feet.
Couldn't see myself on FR24, but then I was in a metal hangar with the doors shut. So next thing is a flight test when the 50hr is finished.
Do you know if you can look at FR24 or suchlike for a flight you have just made or is it only realtime flight tracking.
Thanks for everones help.
John
hi John,
Yes you can look on FR24 retrospectively. There's a menu option at the top of the webpage where you can type in your a/c reg.
I found the trace only hangs around for a few days (maybe a week or so).
Cheers
Andy
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Aha - thats what it was, I had used port 3 but configured port 1 for the Txpdr.
So it appears to work on the ground reporting my own txpdr at my position at 0feet.
Couldn't see myself on FR24, but then I was in a metal hangar with the doors shut. So next thing is a flight test when the 50hr is finished.
Do you know if you can look at FR24 or suchlike for a flight you have just made or is it only realtime flight tracking.
Thanks for everones help.
John
Hi John
more importantly, what are the bits regarding SIL and SDA set to ?
are they captured by PilotAware, and are they correct ?
Thx
Lee
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I think I am in the same camp as Ian Fallon, nothing set in these fields :-\
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I think I am in the same camp as Ian Fallon, nothing set in these fields :-\
hmm, sorry to hear that.
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Hi
Have I not read elsewhere on the forum that these fields only become active after interrogation by ground radar. There appear to be many commercial aircraft that don't reflect these settings all the time in the traffic screen.
Alan
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Hi
Have I not read elsewhere on the forum that these fields only become active after interrogation by ground radar. There appear to be many commercial aircraft that don't reflect these settings all the time in the traffic screen.
Alan
My understanding is these are un-solicited.
I think I was told by Trig, that the messages are output every 2 seconds
Thx
Lee
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Alan,
No, ground radar has no influence on the 'extended squitter' ADS-B broadcasts and no ADS-B messages are sent in response to external interrogation. ADS-B is entirely driven from the broadcasting aircraft.
Please also understand that the SIL and SDA are not fields in a single ADS-B message format. There are many different short message formats that a Mode S ES transponder sends out at differing intervals. Some message formats are sent out more frequently than others.
When viewing CAT ADS-B it is important to understand that there are older versions of the ADS-B standard specification in operation today which don't all support SIL and SDA, and hence you will not see this data for all aircraft.
Steve
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Hi John,
Which USB/ RS232 converter cable did you use in the end to get it working? Did your transponder require true RS232 I.e 12v logic, or TTL (5v)? If 12v, do you know whether the cable required a 12v power connection to power the converter, or is there some clever switched mode level shifting done within the converter to obtain 12v from the 5v USB supply?
Tx
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At the moment it is running on a "borrowed" one from a friend. But I have ordered a similar one and am awaiting delivery. Will report back when I have the new one.
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I've just tried it with a two quid Chinese PL2303 jobbie on a null modem cable to another one plugged into my PC and it works fine for that.
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I've just tried it with a two quid Chinese PL2303 jobbie on a null modem cable to another one plugged into my PC and it works fine for that.
This is exactly the test I made.
I also tried reconfiguring baud rates for both ends, and it all worked correctly
Thx
Lee