> 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 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
