[Elecraft] Connections to K3 ant 1 & 2

[Tom W8JI]

> To add slightly to Joe's suggestion to use a SPDT relay as 
> an alternative,
> if a DPDT relay is used one pole can be used to switch the 
> signal path, and
> by connecting the second pole to ground the second pole 
> can be used to
> ground the unused signal path - which can improve 
> isolation (reduce
> crosstalk) if the ground connection to the second pole is 
> short.

I've seen grounding increase crosstalk or feedthrough also, 
so it is the overall layout and relay or switch that is key 
to whether grounding helps or hurts.

Best to use a form-X or double-make double-break relays and 
let the armature ground but not the poles. It's easy to get 
into the -90 dB isolation range at HF doing that, and still 
be in the 70's and higher at 50 MHz.

I use a manual switch on 6 meters/HF. I have a pair of 
3CX800's on six, and a big amp on HF. No problems using some 
Diawa 2 pole switches.

If homebrewing I would measure things carefully.

73 Tom