[ARC5] ARC-5 bypass caps

[AKLDGUY]

Been working on my 6-9.1 Mc ARC-5 receiver. The dial alignment was off,
with ham SSB signals heard around 6.9 Mc. Rather than start in on
realignment, I decided to replace the bypass caps.

Smashed the mica wafers out and pulled out the interiors from three 0.05 uF
cans (3 caps in each can), then fitted 0.047 uF 630V replacements inside
each can, soldering the grounds to the can through the drilled out hole in
the bottom. Terminated the wiring to the capacitor leads, leaving them
unsupported.

This immediately brought the alignment near correct, with SSB conversations
heard between 7040 and 7100. Seems like only a minor touchup may now be
needed.

This confirms a point that I have made here before; that if bypass caps are
faulty, the tuning is badly affected because the tuned circuits are not
properly grounded at their cold ends, making wiring capacitance part of the
tuned circuit capacitance.

Neil ZL1ANM
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