Thanks for all of your replies. I have spoken to Trig again this afternoon, and their position is, the radio does indeed make this noise, you can lessen it’s impact by turning down your headset volume control and turning up the radio volume. If you still don’t like it, you can have your money back. I told them that I would rather they found a technical solution rather than just relying on customers fiddling with their headsets. Not all headsets have a volume control anyway.
It still baffles me that I appear to be the only one to have this problem.
It still baffles me that I appear to be the only one to have this problem
PROB99 you are not. It is standard corporate procedure to tell everybody that. I do that in my business too (but then I solve the problem properly and fix it for everybody affected). Also many people would not notice anyway (poor quality headsets, etc). Also there is a likely correlation between the headset types used and the type of radio, which may help for it to not show up.
What kind of power supply are you using?
It must be able to give clear audio, as you have experianced yourself on the Aero.
Power is a small 12v battery. 7Ah I think . In a small wooden single seater with no starter motor.
And to be sure, no charger when testing?
Correct, no charger. Just the battery.
I do that in my business too (but then I solve the problem properly and fix it for everybody affected).
You don’t think it would make a better impression in that case if you said that you know about the problem and is already working on it? I know that as a customer, I would be happier because then I
1) Don’t have to spend time convincing the manufacturer that there actually is a problem and
2) Have some confidence that it will actually be fixed.
You don’t think it would make a better impression in that case if you said that you know about the problem and is already working on it?
If it is a problem the customer has found and reported, the standard procedure would be to admit it (of course, otherwise you look stupid) but say that nobody else has reported it.
Then, if you operate ethically, you will immediately fix the problem and send the customer a free replacement regardless of cost, DHL shipping, etc. And you do the same with every other customer who is affected. That way, everybody is happy and your company’s reputation for QA is protected. Thankfully, the last time I had to do this was in 1999… (a tantalum capacitor placed in reverse 
) and we traced all the affected products, about 50, by S/N and replaced them with new ones.
Unfortunately, most modern companies will try to wash their hands of an issue because they are already working on the next version and everybody inside has moved on to that one…
By all accounts, Trig have a good reputation, but I would still not expect any company to suddenly go public with the full extent of an issue. The biggest benefit is achieved by repidly resolving the customer’s problem on a one-to-one basis.
Every 3-4 years my KX155s annoy my ears due to an increasing Noise to incoming Signal ratio which makes far away communications more unintelligible.I am not shure how TX goes.Seems more immune. Besides,we have propagation and altitude effecting this.
The solution for this is to remove my two L/4 Ground plane antennas,rejuvenate with some Scotch Brite the attaching surfaces,wash with a little acid or Cola beverage and finaly apply Alodine to both surfaces.Then screw back and enjoy the new,clear,silent RX audio.
This was for aluminium frames.For wooden or composite,one has to install extra Radials (at least 2) perpendicular to the Whip radiator and under the frame.Less of this,means more noise and less efficiency.
Did you use shielded audio wiring, are your headsets sockets isolated from the aircraft, and do you use the dedicated phone and microphone ground connections? These grounds should not be tied together. Do you know where this noise is comming from?
Try the following: Install a dummyload instead of the antenna, or temporary install a short on the antenna connector, right at the back. do NOT transmit now! Does this change the noise? Reinstall antenna directly after this test.
Are you using the internal intercom? If so disconnect pin 17 at the radio. This disables the intercom. Test again now.
