Solar CB-160 Capacitor Analyzer (1945)

           

I got this Solar model CB-1-60 capacitor analyzer for a few dollars at a swap meet. I use it for checking capacitors, although it can also determine resistance.

The military manual describes the CB-1-60 in detail and it also includes a schematic and parts list that you can use to restore your own unit. Click the icon below to download the manual from the archive.org website:

My CB-1-60 sat forgotten on a shelf for a few years, until someone happened to mention this model in an online forum and I remembered that I owned one! When I saw how simple it is inside, I decided to restore it and try it out.

The first photo shows the unrestored chassis. I'll replace those four tubular paper capacitors and the rectangular box that contains two electrolytic capacitors. (See my recapping article for more about capacitor replacement.)

I also checked the resistors, cleaned the controls, and tested the CB-1-60's two tubes. Here's the restored chassis, ready to go.

You could put the new electrolytics into the original rectangular box, but I simply mounted them on the nearby terminal strip.

The wooden case was a little beat up, so I cleaned it with mineral spirits and then gave it a once-over with Howard's Restore-A-Finish. I also removed the handle hardware to remove surface rust and blacked the worn leather handle with liquid shoe dye. The next photo shows the Solar tester ready to reassemble.

The old power plug was deteriorated, so I'll replace that, too.

My tester was missing its cover, which has a label with condensed instructions. Shortly after I published this article, a fellow collector emailed me this scan of the Solar instruction card.

Now, if I make a new cover, I can print out the card to go with it. Thanks, Kevin!

In the next photo, I'm testing an old "bumblebee" (plastic-coated paper) capacitor. The Leakage lamp on the right is glowing, meaning that the cap failed.

For this trial, I inserted the capacitor's leads directly into the tester's test jacks. You can also plug in probes to connect to a capacitor still mounted on a chassis (of course, one leg of the capacitor should be disconnected for that test).

You can also test a capacitor's value. Here, I have inserted a new, known-good capacitor to demonstrate.

In this mode, you watch the green magic eye indicator at upper left while turning the big center dial. When a dark shadow in the eye reaches its maximum, you stop turning and read the value from the scale.

More tests are possible (read the manual for details), but that's primarily how I use my CB-1-60. A consumer-grade tester like this is suitable for everyday hobbyist use, although it can't match the precision of expensive laboratory or military equipment. And of course, like other 65-year old equipment, it doesn't comply with all modern safety standards. But it's easy to use and effective, as long as you use common sense and understand what it's designed to do.

I own two similar testers, a 1965 EICO 950B and a 1940 Sprague Model 16 Tel-Ohmike.

  

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