[Collins] Collins 32S-3 - part help

[Dr. Gerald N. Johnson, electrical engineer]

I prefer a totally different relay. The original relay was prone to
misadjustment when handled for assembly or when touched with tools while
working in its vicinity or when the terminals were bent to allow
attaching wires. Its an open type of short form telephone style relay.
Hand adjusted at the factory, at one point in early S-line production
the Collins warehouse wanted to save space in the bins by removing the
relays from their individual cardboard boxes. That was a disaster in
production with many relays no longer making contact. The short form
telephone relay also has very little contact pressure or contact wipe,
which makes it prone to failure in the long run.

The later plug in relay was not much better, still a short form
telephone relay, just in a plastic case to protect it from so much
external mechanical abuse but still with the failings of low contact
pressure and very little contact wipe.

I prefer the P&B KHP series relay, an armature type of relay, it has
better contact clearance, better contact wipe, and NO adjustments ever
necessary. It does make more noise. There is one with a 110 volt DC coil
that works fine. Doesn't plug into the Collins socket, but wiring to it
doesn't change the contact positions. Sockets are available. Its not
original to the S-line (would have been if I'd been there for that
design), I don't know if there ever was a Collins part number for the
one I recommend, but I DO KNOW that relays in that family were used,
because I used them. And they had Collins specifications or easily met
new Collins specifications.

73, Jerry, K0CQ

-- 
Entire content copyright Dr. Gerald N. Johnson. Reproduction by
permission only.