B40

On 9 Mar 2005 17:30:05 -0800, John wrote:

I found the source of the problem...I have also installed a B40 Digital
Averager Display (DAD). Basically, if this is connected to the B40, I
get the big vario deflection during transmit. Once I disconnected it,
the B40 was virtually unaffected by the transmit. I connected and
disconnected it a few times to prove it was the cause. The DAD consists
of 4 twisted wires in an unshielded pvc jacket. I ran the its wires
only about 4 inches over to the back of the vario. I guess I'll have to
talk to the manufacturer about it or just return the DAD. I thought it
would be a "nice to have" since I was already in the panel doing work.

I would still look at the antenna connection as suggested by Eric
Greenwell. It seems to me that there is too much RF energy floating
around behind your panel. Maybe a bad shield connection at either end
of the coax cable ? An SWR test would pick this up.
AFAIK, Mike Borgelt's products are fairly immune to stray RF, but if
there is a strong field strength, it will still affect the vario.
Cheers, John G.