Topband: Relays in RX array

Tom Rauch w8ji at
Tue Mar 21 19:02:55 EST 2006

> I had a thread on here last year that discussed the topic
at length.  The bottom line was that all relays will be
flaky due to oxidation and other issue on the
contactors.--unless you run a bit of DC through them.

I use regular 1-2 amp sealed DIP relays, and never once have
had a problem despite having dozens of relays in the signal
path. This is with about 20 years or so of use in some of
the switches. I recently just pulled a box I built in 1983
out of service, and the relays were still fine.

My suggestion would be to buy a low current sealed relay and
not worry about it. If you start to have problems, then it's
a simple matter to add contact bias.

Where I think you will get in trouble is using higher
current open frame relays, even those in plastic enclosures
or covers. They are often  problematic when operated without
contact bias current.

73 Tom

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