Just came back from the hangar. My hangar neighbor is a electrical engineer and was helping me. Tried few things:
Checked all the pinouts on the RST AP and everything was fine
Powered the AP and radio with a separate battery independent from the planes + and- : No change
Installed the 20A Radio Shack filter Bob Nuckols  recommended: No change
BTW Radio Shack has discontinued all the noise suppressors that we can use. I found one left over.
Than I checked with my handheld and my headset inside the cockpit. No connections of any kind to the plane. With squelch on high gain, I can hear all the noises. Than it hit me: there is an antenna radiating all the noises. Bob Nuckols warned against use of wire conduits in both side of the plane.

When I moved the batteries to the nose from the spar a month ago, I run two #2 wires the whole length of the fuselage to the firewall. Being nervous having positive and neg. in the same conduit, I run one in each side.
So, I think I created a very good antenna.
I have a long HD battery jumper cable ready to test instead of both cables in place now, but I got hungry and tired and left it for tomorrow.

Buly