jeu. 10 mars 2016

HP8904A Multifunction Synthetizer Repair: 10MHz output

After having fixed the PSU of one of my HP8904A signal generator, I discovered that the other unit had its 10MHz reference output dead flat.

I've disassembled the main logic board, but unfortunately, the schematic of this later A2 board (as it is referenced in the servce manual) is ...

jeu. 10 mars 2016

HP8904A Multifunction Synthetizer Restoration

What Is This About

I have a couple of HP8904A multifunction synthetizers for years (bought them on ebay around 2007 IIRC). One of them is working properly, but the second one had very inaccurate output levels, generating a non-symmetric signal when output level was set above 5V or something like ...