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LarryT

Well Known Member
The flying RV-6A I bought has an Icom AC-200 radio.

I have not figured it out in the 10 hrs. I have flown. I find the volume and squelch controls very sensitive. I have had "loud and clear" acknowledgments as well as "broken and unreadable." When I flew to Concord, CA, the northern half Travis approach controller made me Ident to acknowledge every transmission. He handed me to the approach controller for the southern half who acknowledged "loud and clear" when I joined his frequency. What gives?

Furthermore, the radio is really scratchy when it receives. I thought it might be my mic but realized that there is A LOT of background hiss when transmission come in from other aircraft transmitting over common frequencies lke 122.9 and neither mic in the plane is open.

My wife has started riding with me and she complained (profusely) about the background static as well. Nothing like the KLX-135A we had in our Cherokee. I really want her to enjoy this experience.

For those of you familiar with this radio, am I doing something wrong? If not, how should I troubleshoot this issue?

Larry
 
My intercom is a Flightcom 403..

...if that is useful information. There are two intercom positions "ICS" (intercom) and "isolate". In the "isolate" position there is no side tone. By reading the manuals it seems that the manufacturer considers this "normal" (don't ask me why. If I used the "isolate" position on the PSE audio panel in my Cherokee with the KLX-135A, I still had a sidetone when I transmitted).

I checked the previous posts but they seemed to be mic related during transmissions. I am getting the same issue with background noise receiving. It is just really poor quality audio. Please don't pull any punches, is this radio just a cheap POS?

I want my wife to be as comfortable as possible in this aircraft. This is something I can change if I have to. There isn't anything I can do about how space confined she feels in the cockpit. I really need to fix every other problem I can. Her willingness to fly with me is an important component of my quality of life.

Larry
 
Hi Larry,
I have the A200 in my -7A and it works great. I've heard nothing but great reviews for this radio and that's why I went with it. It's simple and cheap and works great (at least for most).

It's hard to figure out what could be causing your problems, but I had similar, never-ending problems just like yours when I owned a Pulsar with a Terra 760D radio. I did everything short of rewiring it and never did fix the problem. The guy I sold it to had an avionics shop rewire it and it now works good.

My guess is that you have wiring issues. The good news is that the A200 only has 6 or 7 wires coming out of it, so it's pretty easy to figure out. Then again, it could be your intercom. I'm using a Sigtronics 200S and it doesn't require shielded wiringing on the headset jacks. It works great, too.

As much of a pain as it is, I'd start by looking at your wiring. Then look at your antenna feed line (coax)...maybe put a VSWR meter on it and see what you get. Lastly, make sure all of your systems are properly grounded. If you don't have everything going to a single ground bus, you may have ground loops.

Good luck.
 
LarryT said:
The flying RV-6A I bought has an Icom AC-200 radio.

I have not figured it out in the 10 hrs. I have flown. I find the volume and squelch controls very sensitive. I have had "loud and clear" acknowledgments as well as "broken and unreadable." When I flew to Concord, CA, the northern half Travis approach controller made me Ident to acknowledge every transmission. He handed me to the approach controller for the southern half who acknowledged "loud and clear" when I joined his frequency. What gives?

Furthermore, the radio is really scratchy when it receives. I thought it might be my mic but realized that there is A LOT of background hiss when transmission come in from other aircraft transmitting over common frequencies lke 122.9 and neither mic in the plane is open.

My wife has started riding with me and she complained (profusely) about the background static as well. Nothing like the KLX-135A we had in our Cherokee. I really want her to enjoy this experience.

For those of you familiar with this radio, am I doing something wrong? If not, how should I troubleshoot this issue?

Larry
Click to expand...

I used to use an ICOM A200 in my aircraft before we made our own radios.
It worked very well.
One item that is somewhat critical (with any radio really) is that you avoid feedback from the transmission back into the microphone/intercom. This can result in a whole host of different effects depending how bad it is. From slight distortion when transmitting all the way to howling (very similar to the effect you get if a microphone is too close to a speaker).
This is usualy very dependent on the frequency you are transmitting on. Some may show no or only little effect, others are unusable.

The more powerful the radios transmitter, the more likely this will happen.

The fix is usualy to investigate the wiring to the intercom (both headsets and the connection to the radio). Some intercoms tend to be very sensitive to receiving RF via the headset cables and other connected wiring.

An easy fix is usualy to fit clip-on ferrites that are made for the VHF band (such as you can find on our Website under accessories). These are either clipped over the cables close to interferers (items that may transmit interference on VHF channels - such as EFIS systems and other digital equipment) or they are clipped over the cables close to the items that are interfered with (in your case that would be the intercom cables and perhaps the intercom cables leading to the ICOM). These ferrites can be very effective as they do a good job of blocking (or at least greatly reducing) the amount of feedback in the system.

BTW: Don't use the ferrites often found in electonic or ham radio shops - they tend to be made for the short-wave bands and are used by radio hams to keep their neighbours from burning their radio masts down. They tend to have little or no effect at VHF frequencies.

Rainier
CEO MGL Avionics
 
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