[VHFcontesting] Multi-pole relays with 28V common??

John D'Ausilio jdausilio at gmail.com
Thu May 7 19:17:39 EDT 2020

I've had a pair of 1P3T SMA latching relays in my relay box for a while,
and thought I'd use them for a 144/222/432 switching box for my K3. They
have one terminal marked +28V(COM) and three terminals marked -1, -2, and
-3. For some reason, the +28(COM) terminal is actually at RF ground, which
I realized when I connected system ground to the chassis! I see in various
catalogs that these relays are offered with negative or positive common ..
how the heck can you actually use a positive common relay without having
the chassis at +28?

Dynatech M3-413D38FT

de w1rt/john

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