RESOLVED - Help Identify this Component - Feedthru RelAY?

[NY2KW]

I am repairing an old meter test set for a Collins Radio power supply.  The test set was likely built in the 1960 - 1970's.  It has 10 meters monitoring all aspects of the power supply, eg hi B+, lo B+, filament  voltages and current under simulated loads (via very big wire wound resistors) or with an actual transmitter as the load.

There is a component that looks like a feedthrough capacitor but its functioning like a simple SPST NC.  Unpowered it shorts out a string of resistors to ground I assume as a bleeder safety in case the power supply bleeders fail for any reason.  When the meter test set is powered up with the AC mains, this little feedthrough component disconnects the resistor chain from ground.

I think its working intermittently and sometimes not opening the ground lead when powered on.  Does anyone recognize this to help me search for an original replacement?

TIA,  Jerry

[Wolfram]

That's a Gigavac ceramic vacuum relay, these can do serious voltage and current but at a cost. https://www.mouser.fr/datasheet/2/657/sensata_g41c_series_spdt_high_voltage_relay_datash-3104309.pdf
The flange doesn't serve any electrical purpose so it's not acting like a feedthrough, it's just for mounting.

[NY2KW]

Thank you, that's really interesting.   There is about 1kV across the resistors.  The power supply (516F-2) is all DC loads, so I don't know why they went with an RF rated relay.  Maybe that's what they had easily available.  I was told by some ex-Collins engineers this was custom made at Collins in their service department, but others have said i's just someone's homebrew. Regardless, the quality of the build and layout are quite professional.

Merry Christmas and Happy New Year!

Jerry NY2KW