Audio Testing

[AllanBirt]

Thanks Lee,

After many hours of trying to identify this issue on a newly built SKR and now I'm back to square one...

I know its nothing to do with any power supply & groundings within the aircraft as I have fully gone over everything yesterday, plane still in bits, even tried 3 USB car power sockets and get the same result, 2 of them being the Anker brand as recommended 

Strange thing is, when the PAW is powered off all is ok  , when you power up using plane power then the noise begins 

So I'm at a lost.... I see your aircrafts been buried at the back of the hanger 

Allan

[exfirepro]

Hi Allan,

I tried my Trig contacts earlier, but for some reason they are not answering. I left messages so they will hopefully return my calls. In the meantime I have been reading the Trig Documentation and re-reading all your posts in this thread yet again to try to get to the root of your problem.

The only thing that has come to notice is that you say you connect your PAW audio lead directly to your Bose A20 headset, i.e. bypassing the radio/intercom. Have you tried feeding the PAW audio via the Aux Input (pin 20) on the TY91 instead?

I would be tempted to make up a 'screened' lead using your 4-pole 'TRRS' jack plug for the PAW end. You can use either left or right audio from the Raspberry Pi 'Tip' or 'Ring 1' as the PAW audio alerts are Mono. Connect ground from 'Ring 2' via one of the other wires inside your cable and also connect the cable braid to 'Ring 2' at the PAW end only to ground the screen at the PAW end. You should be able to make a temporary connection from your chosen wires to pin 20 and ground in your TY91 plug for test purposes. Worth a try!!

Regards

Peter

[AllanBirt]

Hi Peter

would love to use pin 20, for AUX input to Trig, but I'm currently using this for my MGL Efis Explorer lite, I may have to go down the Bluetooth option

Allan

[exfirepro]

Sorry Allan, I forgot about that.

It just occurred to me that feeding the PAW audio via the TY91 would tie the two grounds to the same level which might negate any 'loop' issues. I take it your ground loop isolator hasn't arrived yet?

Peter

[Admin]

I see your aircrafts been buried at the back of the hanger 

Yes, no need to remind me 

[AllanBirt]

I take it your ground loop isolator hasn't arrived yet?

Nope... still patiently waiting, should of been here on Friday. Not even received today so emailed them  this morning to find out they're on holiday till the 14/1/17, but it was posted on Wednesday. Hopefully it might turn up tomorrow 

Lee, popped into Sywell on my way home this evening and noticed they have removed your wings and stripped the coverings...... oh sorry that wasn't yours that's in for a major overhaul 

[Admin]

Lee, popped into Sywell on my way home this evening and noticed they have removed your wings and stripped the coverings...... oh sorry that wasn't yours that's in for a major overhaul 

 

[AllanBirt]

Hi Lee

Just sent you an email for a replacement licence

Allan

[AllanBirt]

OK, update on my interference issue.....

Trig saying all wiring to my TY91 is all OK, as standard communication is all clear, only when there is no transmission taking place you get the interference with PAW being plugged into my headset.

They have quoted the following 'USB chargers/adapters are fast becoming the no.1 RF noise problem for installers', now I've tried 2 Anker USB charges as well as another brand I borrowed from another SKR (not yours Lee  ) and I get the same result. I am now looking to changing my cigarette socket that this plugs into to see if this could make any difference, I don't think it would but I don't know what else to try.

[brinzlee]

I give you full marks for perseverance !! So in summary in can only be a ground loop even though Trig are telling you that you're wiring is correct.....this would be solved with either bluetooth transmission or ground loop isolation transformer....I would try the transformer first......Then if it still persists, its the power supply....The best solution to that is the charge2 / charge4 device installed
http://charge4.co.uk/                     
The specification on these units far exceeds the cheaper Korean/Chinese plug in adapters, especially if you have sensitive  issues. I really wouldn't think changing the 12v cigarette lighter socket will do much

[exfirepro]

Allan,

Out of interest, who was it at Trig who replied?

I concur with Brinsley, worth waiting and trying your ground loop isolator first. If not successful I can definitely recommend one of Jeremy C's power supplies. I have had a Charge 4 running in my Flexwing for almost a year now and it's the bee's knees. The smaller Charge 2 version comes as surface or panel mount. Both highly recommended.

Regards

Peter

[AllanBirt]

Out of interest, who was it at Trig who replied?

The contact at Trig was Lindsey Christie, same person I was emailing when I had issue with MGL and Trig compatibilities, all resolved now tho

[exfirepro]

Thanks Allan,

Thought it would probably be Lindsey or James.

Regards

Peter

[John.Riley]

Great thread about the audio output from PAW. I fly a single seat aircraft so no intercom. I have had to use a slightly different setup than most. The amp and PAW are behind my seat so I was hoping to fine adjust the volume on my ipad, having set it max in the amp. All seems to be fine, just waiting for the volume fix, mine is permanently on 10. Attached diag of my setup.

[exfirepro]

Hi John,

Thanks for the info. Looks like a neat setup. Hopefully we'll get the audio setting problem sorted soon.

Regards

Peter