Hi,
I am trying to repair a venerable HP 8662A Signal Generator. No need to make the presentations of the generator I guess.
During my repair, I noticed that two key springs were missing. Unfortunately, these key buttons are very hard to find now. Or at indecent price.
Fortunately, I found one of the missing springs in the enclosure, but only one. So I had to find a solution for the missing one. And while I was waiting for a quotation from a local spring manufacturer, I had the idea to try to use some packaging plastic and cut a poor-man's spring in that. I tries several widths, and found one that seems to work just fine. The feeling is a bit softer than the other keys, but overall, it works very nicely. Not sure it will last a long time, but hey.
Just in case, might help.
If someone is interested in the repair of the generator itself (for which I had several issues with the PSU and the LF section), I am writing a series of blog posts on
https://whatever.sdfa3.org/hp8662a-synthetized-signal-generator-part-1.htmlDavid
Neat fix
. And if it doesn't last long, (although I'll bet it will,) cut another !.
That's a very interesting idea. I've had issues with those before, and went in and flipped over every one of the steel springs to get them to react better after so many years. It's ideas like this that make this forum a very special resource.
(from blog) Carrying the unit from my cellar to my appartement was some kind of a job: it's a robust 30kg device I had to climb the 7 levels: no lift in the old parisian building I live in...
That's nothing short of Herculean.
8662As are
heavy.From your photos, it looks like someone has already replaced at least one of the capacitors on the power supply transformer PCB (A7?), but don't forget to check the ESR of all of them, especially the capacitive voltage divider.
(from blog) Carrying the unit from my cellar to my appartement was some kind of a job: it's a robust 30kg device I had to climb the 7 levels: no lift in the old parisian building I live in...
That's nothing short of Herculean. 8662As are heavy.
Yep that was a pain in the neck. Once upstairs, took me 15mn to recover :-)
From your photos, it looks like someone has already replaced at least one of the capacitors on the power supply transformer PCB (A7?), but don't forget to check the ESR of all of them, especially the capacitive voltage divider.
Yes, the unit has been repaired several times I think. There are several evidences of repairs, and there is also an Agilent sticker somewhere on a board.
David