Greetings to all,
After a long search for a replacement for the push-button switches in
my Alpha 78, I thought I had found them at, of all places, Walmart. You can
not just go pick them up. You must order them online. After a three week
wait, the switches finally arrived. They are the modern version for the Alpha
switch, but not an exact replacement for the 50 year old switches. However,
the internal switch contacts in the new switches are exact replacements for the
contacts in the old switches. These new contacts appear to be silver ( at
least in color) plated. The contacts in the old switches appear to be made of
copper, or bronze, and, in my case, were badly pitted from nearly 50 years of
use.
The new push-rod will slide into the old switch body but will not larch
properly. Two tiny contacts and springs are attached to the internal
push-rod. The springs and contacts must be removed from the new push-rod and
installed on the old push-rod. Do not cut any wires. Do not remove the small
circuit board attached to the bottom of the switches. Just remove the meters.
The entire switch assembly can then be unscrewed from the chassis and rotated
up through the meter hole for relatively easy access.
It is not an easy job, in fact, it was a very meticulous job for me. If
I can do it at 81, you youngsters should have no trouble. It might take a
little practice and I suggest you get a magnet on a stick to retrieve the tiny
springs that will shoot all over the room. Be careful, the springs are
magnetic, the contacts are not.
The project is really worthwhile. After several hours of quite
meticulous work, the multi-meter switches on my Alpha 78 works like new
73 de Lon, K5JV
281-795-1335
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