I’ve acquired a nice HP 3330B Automatic Synthesizer after some testing it started up with a wrong value on the amplitude display.

Some testing revealed some other quirks when I want to alter the frequency it displays the input on the amplitude display and changing the frequency and amplitude with the up down keys also gives strange results on the display, also some other keys don’t work as they should.

After some searching, I’m convinced something is wrong in one of the processor boards. I’ve looked with the logic analyzer and can see the logic is starting up as it should it follows the state diagrams in the same order as in the service manual.
I’ve tested measured a lot and can’t find the fault at the moment, so I’m looking for a working set of logic board (A7 ALU board and A8 control board) and if some body have them an image of the control roms (4 x 256bit ROMS) so I can check these against the images I’ve made of my ROM’s (82S126 compatible).

If someone has a set of boards ?(A8, HP 03330-66575 and A7, HP 03330-66507) and/or the rom images, that would be very nice and should make me possible to fix the 3330B so I can use it in conjunction with the HP3570A to restore a HP 3041A VNA.

?

-Rik

?