Atlas:
I have said several times on this thread:
The interference is internal to some aircraft, not coming from an external source.
Thanks for trying it out for me, it looks like some machines get it, others don't.
I have PMed some others for more details.
Anybody else who wishes to try it out, please make sure you have everything running, radars, EFIS or whatever, before you dial it up.
Thanx to all for your assistance.