AO 1031 Illuminator Potentiometer question

[vgwhite]

I recently acquired a Series 10 with the 1031 Illuminator basically for parts. The illuminator lights up when I turn it on, but it immediately goes to full brightness and stays on full as you turn the knob. I'm guessing that the potentiometer is bad. Can anyone confirm this and / or give me advice if this is repairable? Replacing the potentiometer looks straightforward assuming one can be acquired. Does anyone know the specs for this potentiometer and a potential supplier.

Any help would be greatly appreciated.

Thanks

[apochronaut]

Kudos to you for repairing. All too often stuff is just chucked in the mountain of trash this forgetful culture of ours has quickly amassed. That's o.k., we can always just start dumping it on the moon.
The pot is a type 055 made by CTS. It is a 3A, 125v. A.C. 2 ins and 2 outs with one unused tab. The four folding clips on the front can be pryed back to open it up for cleaning. That might work but it also could be too badly burnt for that.
If you end up needing a new one, check ebay under CTS potentiometer or pot or variable resistor. Similar or the same are used on Fender guitars and likely others, so there are lots around and they are cheap.

Nothing else except the 4 screws, bottom plate , allen screw in the knob( 2.5 mm I think) and the 1/2" shaft nut and lock washer needs to be removed to get it out. It is a tight fit and there is a plastic insulating cowling around the shaft. Be carefull not to dislodge the mirror, the edge of which overhangs it's backing, right below the clearance for the switch. Using the wiring harness, as a positioner with your right thumb and forefinger while you keep a bit of pressure on the shaft with your left index finger is the best procedure to get it out because the threads drag in the mounting port during withdrawal.

[vgwhite]

Thanks, Apochronaut! I'll try what you suggested and post the results when I have them.

I've looked at many of your posts - your depth of knowledge about microscopes is amazing. Thanks for all you have contributed to this site.

Regards

Vince

[apochronaut]

I 've goofed around with enough of this stuff for long enough that I've filtered out a few bits of info. to pass along. Thanks for the thanks.
In this case , it doesn't hurt that I have fixed a few electric guitars too.