We are trying to get a vhf radio to work in our Avid heavy hauler, 582 blue head.

In my experience when having radio problems it is in the recieve.

We are having a problem in the send.

We have a "normal" installation with the electrical components that came with
the new engine, new regulator, plugs wires and caps.

Recieve is loud and clear but when we transmit all we send is a loud squealing
sound with a barely readable voice.

We tried several radios, all handhelds, and all were the same
We tied two different antennas in two different location still no joy.

I read thru the Avid forum and one of the items mentioned was shielded wires to the
mag kill switch, did it, still no change.

Others mentioned getting rid of the resistor plug caps?

I have considered replacing the copper core plug wires with carbon core?

It is not a variable rattling noise like it would be if it was spark plug
related

The next thing I might try is a new regulator and then stator. Expensive.

It makes no difference if it is plugged into A/c power or on it's own battery so
it is not coming thru the wires.

When I move the handheld away from the airplane at about midwing it is better,
at the wingtips it is fine, so it is definately RF interference.

We have a metal firewall so whatever it is (is) strong enough to overcome that
barrier.

The only thing in the cockpit is the Tinytac and unhooking it was no help.

Help is what I need, suggestions would be appreciated.

Ray