Rosetta Interference

[jodel123]

I have a Rosetta which initially worked however, now with the power cord attached to the prescribed power scource it produces a loud howl from the audio out. Has anyone an idea which would help ?

[Admin]

Hi

Can you tell us exactly which power source you are using.

You say the audio out produces a howl, you do not describe the audio out connectivity or source
Bluetooth, Wired, to-headset, to-intercom

now with the power cord attached to the prescribed power source

Does this imply using a different source, does not produce this problem

Please try to describe as much as you can about all the components in your setup, what works and what does not

Thx
Lee

[jodel123]

Hi

The power source is using an Anker cig. lighter and the lead supplied with the Rosetta. Audio out is via a 3.5mm stereo lead from the PAW to to a Lynx intercom/radio aux in. The complete Lynx system including headsets is used.I have not tried any other power source. I have though tried 3 different Anker 4.8A charger with similar effects.
The interference does not sound like an audio feedback

[Admin]

The RPI uses a 4 pole TRRS connector
https://www.raspberrypi-spy.co.uk/2014/07/raspberry-pi-model-b-3-5mm-audiovideo-jack/

are you using a 3 pole or 4 pole lead ?

Some users have reported issues with 3 pole audio leads.

Also, do you have another audio player you can try connecting USB speaker or something similar ?

Thx
Lee

[mariko]

Question: Using a headset with microphone, commonly supplied with smartphones, maybe a good test to exclude any  Rosetta related problem?
If the howl disappear, power supply and Rosetta are ok and the problem is from the audio cable and beyond. If the problem persist, you have to investigate further your power supply and the Rosetta itself. Am I right?

[Paul_Sengupta]

Sounds like it could be a ground loop. Have a look on Amazon for an audio ground loop isolater. There are threads on the forum here somewhere about various units that people have bought.

[exfirepro]

Hi Jodel,

Are you only running PilotAware from your Anker Supply, or do you have another device plugged in to the second USB port? A low charge level tablet or phone, for example, can easily draw off most of the available current, causing PilotAware to ‘brown out’ or shut down.

Like Paul, however, I suspect that what you are suffering from is ‘howl round’ caused by an electrical ‘ground loop’. I have used an ‘Aukey’ ground loop isolator (available at £9.99 from Amazon) to good effect in the past to cure this problem in another PAW user’s aircraft. It’s certainly a cheap and easy option to try. There are also several other similar options available on Amazon and elsewhere, some of which are identical in price and appearance to the Aukey (presumably from the same factory) and some cheaper. They should all perform the same function, though I can’t personally speak for the cheaper versions. Several other PilotAware users have however used these and similar devices to cure similar problems.

Regards

Peter

[jodel123]

Thank you for all the suggestions.  My audio lead is a 3 pole so I will try a 4 in the first place and see what happens.  I did not use the Anker for other appliances at the same time.

[Admin]

Hi Jodel,

I think the more likely issue is probably a ground loop TBH

Thx
Lee

[jodel123]

Hi
I forgot to add that this noise is present only when the engine is running.

[Keithvinning]

What engine is it
Might be a clue here

Keith

[jodel123]

A65 with starter and alternator

[exfirepro]

OK, so that would tend to rule out the PilotAware itself as the noise source, (though a Ground Loop Isolator may still be the solution).

The best way to prove whether this is interference coming through the power feed cables would be to try running your PilotAware on a battery pack. You could perhaps borrow one for a test. If it is coming through the power feed, you either need to track down and fix the problem - which could be with your aircraft’s ignition or charging systems - or you can try filtering the supply lead by, for example, fitting a ferrite core or car type interference filter on the power lead to the socket that your Anker adaptor is plugged into. If this doesn’t cure the problem, I would recommend considering one of Jeremy C’s excellent aviation designed Charge 2 or Charge 4 power supplies.

Alternatively, give a Ground Loop Isolator a try first.

It’s difficult to be more specific as electrical interference in vehicles/aircraft is often ‘unique’ to the vehicle and far from easy to diagnose (especially remotely).

Best Regards

Peter

[jodel123]

Thanks for the info.  I am pretty sure now the the noise is from the alternator.  I am awaiting delivery of a suppressor and will have to try that., Cheers

[exfirepro]

Hi Jodel,

Please let us know how you get on. Thanks.

Regards

Peter