[Elecraft] KAT-500 problem

[Don Wilhelm]

John,

It sounds to me like you actually do have some kind of antenna effects 
floating around in your shack.
Pickup from RF on the outside of the coax being conducted to the ground 
plane of the receiver through some "sneak paths".

What happens if you disconnect the receiver from the KAT500?

How close are your antennas to the shack?  Maybe direct pickup by the 
circuits in your receiver is possible.

Do you have all screws in the enclosure for the receiver, amplifier and 
KAT500 installed and secured?

Check the coax between the receiver, amplifier and KAT500 for tightness 
- replace with known good coax jumpers as a test.

Try bonding wires between the receiver enclosure, to the amplifier 
enclosure, and then on to the KAT500.  You can connect the KAT500 end of 
that bonding chain to your shack ground.  That gives a better path than 
grounding each piece of equipment to a single point ground.
Even if you have each piece grounded, try adding the box to box direct 
bonding wires.

73,
Don W3FPR

On 11/23/2019 4:12 PM, jdfreed at bellsouth.net wrote:
> I have a KAT-500 at least 4 years old.  I can hear stations without any
> antennas connected to it.  I live in Clarksville, TN and I copied  station
> in Bradenton, FL 600+ miles away on 14.3 MHZ.  I have had the same thing
> happen on 40 meters as well.  Any ideas???