The original 1762F/CM1762 bulbs aren't available in the quantity needed. I purchased the recommended CM2187 substitute. You can see in the pictures below that they matched the surviving bulbs well.
I removed the switch assembly from the front panel so I could fix the
handles and check the switches. Since the switches can have higher resistance
than the margin switches and still work ok in the front panel I tried just
using contact cleaner on the switches. They work pretty well but don't
register properly often enough that I will take them apart like I did
with the margin switches.
I found that the tabs were broken off some of the switches.
I drilled the switch handles to
allow a metal pin to be inserted. After
installing the handles a few would move back slightly after you flipped them.
That motion was enough to turn the switch back off.
The handle was too tight on the switch at the
limit of its travel. I had to file a slight bit of the inside edge of the
finger of the handle that was rubbing on the opposite side of the switch.
Filing the edge didn't effect its maximum travel since the
tips of the finger set the limit of motion. I assume that I got the pins
slightly off center though I used a fixture to try to get them all in
the proper location. It has been suggested to me that a pin which will break
if the switch handles are hit again will prevent damage to the handle and
switch. The person used a wood pin for his repairs.
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Up to straight 8 restoration
Removed (1.8M) Damaged Wires (1.4M)
Bad Bulbs marked (1.6M) Bulbs (1.9M) Bad Bulbs (1.6M) Bulbs replaced (1.6M)
Back of Front Panel (1.5M)
Broken Handles (526K) Rusty Switch (1.5M) Drilling Fixture (1.4M)
Fixed Handles (760K) Reinstalled (1.4M)
We Have Light (1.5M)
Feel free to contact me, David Gesswein firstname.lastname@example.org with any questions, comments on the web site, or if you have related equipment, documentation, software etc. you are willing to part with. I am interested in anything PDP-8 related, computers, peripherals used with them, DEC or third party, or documentation.
PDP-8 Home Page  PDP-8 Site Map  PDP-8 Site Search
Mirror site if this site is slow highgate.comm.sfu.ca
The following picture links also have descriptions of what is shown in the pictures.
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Next functional restoration Up to straight 8 restoration