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

John D'Ausilio jdausilio at gmail.com
Fri May 8 13:43:16 EDT 2020

There are definitely diodes in there, won't work with -common. I'm going to
try and get it open and see how the +28 is connected to the frame.

On Thu, May 7, 2020, 19:17 John D'Ausilio <jdausilio at gmail.com> wrote:

> 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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