I have been using the Dow Key Series 71 (6 pos) and Series 72 (3 pos)
since the mid 60's as remote switches (one or the other of them has been
at the top of the tower since 1968), with no problems on receive. The
contacts are specified as"Fine Silver w/Gold plate". The contacts are ~
1/4 inch diameter, domed, and have a nice wiping action when actuated by
the ports individual solenoids. These were specified at 1 KW RF to 200
Mhz and 750W to 500 Mhz. The catalog also mentions switching receiver
antennas as an application. To bad they have been discontinued for some
time. If you see one at a ham fest don't let it get away.
Frank W9JCC
On Thu, 28 Mar 2002 10:02:03 -0500 brewerj@squared.com writes:
> jirka@jimaz.cz mentions:
>
> >How much current you have there from 1mikroV signal into 50Ohms
> from the
> >antenna. !?!?!?!?!? On transmit the nonconducting layer which
> develops
> >on the contacts will brake through and no problem but on receive of
> tiny
> >signals ?
>
> Just about every old high power used a dow key relay , or some type
> of open frame DPDT relay, and I doubt those were gold plated. I
> certainly
> have not noticed any deterioration in signal with those rigs that
> are still
> connected via a dow-key (or similar) KW relays with standard
> contacts!
>
> 73
> john wb5oau/4
>
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> Towertalk@contesting.com
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>
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