[Milsurplus] TCS PSU question

[Laura and Jim]

I am assisting a fellow TCS-er in the debugging of his '40's-vintage AC powered PSU: 409M-5 The beast w/the 2 lifting handles and all the "ironwork" on the upper deck. This thing has a pair of small 0.25mfd bathtubs w/matching series resistors mounted on the central bulkhead. One (C307) got warm (leaky) along w/its resistor (R301) during an initial runup w/ a variac set at 45VAC: and easy replacement.

My question: I looked these up on the schematic in the "second echelon" manual, and they appear to be in series on the hot and neutral sides of the AC input.  Why was this done? C305A and B also in series on the neutral/ground side. Why?

Jim Falls
KG6FWT
Eureka, CA

PS: I now know how a full wave bridge selenium rectifier (CR301)smells as it dies. This is the one that powers the relay (K301) in the TX portion of the PSU. I thought these were '50 inventions. When did they start turning up? It's referenced in the manual, so it's stock (12V/300mA).

PPS: Looks like MRCG in SLO is a go again this year! HooRah!
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