Test Equipment Anonymous

Next project. hp 211A Square Wave Generator. From Facebook Marketplace. Extremely dirty on the outside and the cabinet will need re-painting. Papa Smurf's paint shop will be opened and will spray it gray.




Inside is not too bad and is complete. There are lots of crapacitors that will have to be changed including at least 4 black beauties.

The front panel cleaned up well. I used automotive polishing compound on the aluminum frequency dial and it got rid of 90% of the surface corrosion. The corroded BNC connectors will be replaced.

Next up is cleaning the case in prep for paint. The actual painting may have to wait since it's done outside and the weather is still chilly.

There will be no attempt at power up until after the PSU caps are replaced.

It's coming along nicely. I assume you will spray paint the case.

You'll also have to make up a cursor, since the original has been broken off.

Mike, that's cleaning up very nicely! You may motivate me to get mine out of the basement and give it some TLC...

-Pat

Very nice.



My slightly newer sibling says hello.

The only mod I had to do to it was to remove the substandard mains input, and replace it with a modern one:

Some time back I also snagged their later, much simpler sand filled cousins - the 220A and 221A. The 220A outputs a negative square wave, the 221A a positive one. Both are badly in need of cleaning and restoration, as one needs a bit of imagination to consider their outputs to be square waves. Interestingly, both are early examples of their respective engineering revs, the first being the 92nd off the line (815-00192) and the second the 98th (927-00198). As I recall, I had that search going on the Bay of Malcontent for quite a long time; I don't think they sold particularly well (or perhaps were considered disposable; list price for either in 1969 was $195 while the 211A was $400 and the 211B was $450).





-Pat

MED6753 wrote: ↑Mon Mar 03, 2025 10:46 pm Next project. hp 211A Square Wave Generator. From Facebook Marketplace. Extremely dirty on the outside and the cabinet will need re-painting. Papa Smurf's paint shop will be opened and will spray it gray.




Inside is not too bad and is complete. There are lots of crapacitors that will have to be changed including at least 4 black beauties.

This looks like a neat project. From the pictures it looks like it's a mix of original and replacement tubes in there. Also, is the one 0.1 MFD capacitor visible under the chassis an American Radionics Ceracap? The package kind of looks like one of those.

Cubdriver wrote: ↑Wed Mar 05, 2025 8:16 am Some time back I also snagged their later, much simpler sand filled cousins - the 220A and 221A.

Those are SO cute! Thanks for posting.