Topband: Relays in RX array

[Pete Smith]

Can anyone point me toward a practical circuit for running a few ma at 12 volts through the relay contacts of an antenna switching system, so as to keep oxidation from building up?  The subject has been discussed from time to time here but I don't recall any references to an actual circuit.  I will have 12 volts available at the relays, but am unsure how to handle isolation of DC and RF circuitry.

Thanks in advance.

73, Pete N4ZR
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