PilotAware Rosetta- Trig TT21- Wiring Loom - F I X E D

[Gramac]

Hi,

I have the new PilotAware Rosetta and ordered the Trig TT21 transponder which connects to the PA to provide enhanced positional fix.  I ordered the bespoke wiring loom from Mendelssohn Pilot supplies as advised on this forum.

When I have come to look at installing it the USB connection supplied as part of that wiring harness does not appear compatible with the socket on the PA Rosetta. (For some reason I cannot upload a photo in any format at all).

When speaking to the technical people at Mendelssohn they have always installed a USB connection when linking the Trig to the PilotAware.

What’s changed and what do I need to do please ?

Thanks

Graham

[Ancien]

The trig TT21 wiring harness does NOT have a USB connection. It only connects from the remote mounted transponder to the panel mounted controller.
Two separate wires on this harness are labelled GPS position in and GPS ground. These are the wires that you need to connect to your Rosetta.
You will need one of these:
USB-RS232-WE-1800-BT-0.0 from Farnell.
Connect the orange wire to GPS IN  and the black wire to GPS ground. [the other wires are not used.]
Plug the USB end into your Rosetta spare USB socket and then configure that socket on the PAW to TRIG - Please READ the PAW manual on how to do this.
The TRIG TT21 will also need to be configured - yet another manual for you to read.
It will work.
I know!

All this information is here on these pages [ad infinitum].
It would really save you a lot of angst if you did a bit of research on what you were buying.
A lifetime in aviation has taught me RTFM.
I do appreciate you need to ask so please take this in good heart. You will succeed!
Cheers
Bob

[Gramac]

The wiring harness supplied from Mendelssohn for the Trig TT21 to connect to the PilotAware Rosetta DOES have a USB connected. It comes out of the back of the 25 pin connector that attaches to the remote mounted transponder. From what I can see, there are six wires connected to that USB connector.

There is no USB socket on my PilotAware Rosetta that I can see, as if there was I wouldn’t be so confused.

The Farrell part number USB-RS232-WE-1800-BT-0.0 is exactly the same connector that Mendelssohn have used in their supplied cabling harness.

Regards,

[Paul_Sengupta]

The USB sockets on the Rosetta are under the removable cover on the other end from the aerials.

[exfirepro]

Graham,

Very helpful of Mendelssohn’s - I know they make up custom harnesses, but wasn’t aware they were doing them for PilotAware (though knowing Danny, I’m not surprised). As Bob has already said, you also need to configure the relevant Rosetta USB port via the Rosetta Configure Screen (probably Port 2 - at bottom left assuming the Rosetta dongles are in their usual slots) to ‘Transponder Trig’ and either 4800 or 9600 Baud (and don’t forget to save the changes).

You also need to make a couple of settings changes in the Trig (unless Mendelssohn’s Techs have already done this for you). Notably, - GPS source to NMEA 0183 at the same Baud Rate you have set in PilotAware and 1090MHz and 978MHz receivers both to NO (PilotAware doesn’t qualify in this case). There are some other less important settings which you will find in the Trig Manual. Any doubts, please ask! (I have done quite a few now).

Regards

Peter

[Gramac]

Very helpful, thank you.

Graham

[Gramac]

I managed to fly test this configuration today following a long rest due to the weather and other incumbents.

Two issues - Firstly I noted on the Trig 21 display that the following message was displayed : “WARNING - No ADSB Pos” so I am making the assumption that the configuration is not quite right. What have I done wrong ?

Secondly - although I could receive ATC crystal clear they reported that my speech was distorted to the point of being barely readable.  I have noticed that when I turn on VOX to remove background noise there is a small and low in volume, regular clicking of static which disappears when I turn off the transponder. The static I hear and the reported distortion to ATC may not be connected so I’m having my helmet refurbished to rule out the helmet headset. ATC did say that they were having atmospheric issues affecting the west of their position which is where I was.

All help, as always, is gratefully received.

Thanks _ Graham

[Ian Melville]

Your first issue should have been apparent on the ground?

Can you post the port settings you used on the PAW(screenshot preferred?) and on the Trig, also a which USB port you used on the PAW (Photo?)

Cheers
Ian

[Gramac]

Yes, it was apparent on the ground.  I will pop up on Tuesday again and get the settings you require. Thanks

[exfirepro]

Graham,

I take it you did check (on the ground before takeoff) that your PilotAware GPS had a position fix? (Check this on the PAW Home Screen from 192.168.1.1).

The usual reasons the setup doesn’t work are....

1, Firmware too old - this shouldn’t apply as you have just bought the Transponder.

2. Wrong (or no) USB port configured in PAW to ‘Transponder Trig’

Ports are numbered ...

Ethernet.    1.     3
Ethernet.    2.     4

Remember that You MUST remember to click ‘SAVE’ on the PAW Config Screen for the changes to take effect.

3 Baud rate different in the PAW USB port setting to that set in the Trig Configuration - try 4,800 Baud first and if that doesn’t work change BOTH to 9,600 Baud and try again.

4.  Wrong GPS Input (must be NMEA 0183) or wrong Baud Rate selected in Transponder - see Section 6 of the Trig Installation Manual. Most of the settings are self explanatory and in most cases won’t stop the system working, though you need to get them correct to obtain mod approval.

In particular...

TIS output should be set to ‘None’

GPS Certification MUST be set to ‘Uncertified’ - if this isn’t listed, you need to check the correct setting with Trig.

1090MHz Receiver Installed - Set to ‘No’ - PAW doesn’t count.

UAT Receiver Installed - Again, PAW doesn’t count even if a second SDR has been fitted.

Please let us know how you get on.

Regards

Peter

p.s. Also make sure you have the correct ICAO Hex Code for your Aircraft in BOTH devices.

[Gramac]

Thanks Peter,

Yes, PA had a fix on the ground and also in the air.  I will go and check the settings again on Tuesday and report back.

Many thanks

Graham

[PaulSS]

As the forum rank amateur I would also check to see how close your radio and transponder coax cables are. If you are getting transponder 'clicks' through your headphones it may be just a simple matter of the two coaxeseses being too close to each other.

[AlanG]

Hi Graham

Our syndicate a/c has both Trigg transponder and also the Trigg radio and when we had a Flycom intercom the Xponder clicks were there along with the strobes too.  We rewired the a/c to use the built in Trigg radio intercom and this reduced the clicks but did not silence them altogether.  They are certainly not intrusive now.

Alan

[Gramac]

Hi,

I have attached a few screenshots of the configuration , but can only post one photo per post for some reason.

Baud rate 9,600 on Trig and P/A
GPS Input is NMEA 0183)
TIS output should be set to ‘None’
GPS Certification MUST be set to ‘Uncertified’
1090MHz Receiver Installed - Set to ‘No’
UAT Receiver Installed  - Set to ‘NO’
Correct ICAO Hex Code for your Aircraft in BOTH devices.

[Gramac]

The other images are coming.