- 2026
- Jan
- 15
A Waterman OCA-11A “industrial / pocket” oscilloscope - Part 3: Final.
About a year ago, I had a small Waterman “pocket” scope on the bench. It needed some tubes, and had a bad power switch. In an effort to clean up the pile ‘o stuff waiting for bench time - here it is.
First thing I wanted to do was verify that the switch was indeed open, and it was:
By the condition of the unit, it was used quite a bit. Maybe one of the conditions that cause this device to be retired was that open switch. It was easy enough to fix, just a jumper across the terminals. Before attempting to plug it in, I verified that it had a fuse in it, and it was good.
There aren’t any shorts, I can see the transformer load on the cord. Plug it in! I can see tubes lit.
But, there’s nothing on the screen. I mess with the controls for a while and let it set. Nothing. Upon powering down and opening, I notice I can’t detect any heat on the neck of the CRT. Well…it may be open or have some other fault. That’s a show stopper here, and I remove my new tubes for later use.
This guy goes into the donation pile. Perhaps someone can make use of the parts.
Previous part of this series: https://wereboar.com … oscope-part-2-tubes/