I use a HP 8656B! but still need a stereo multiplex unit (new project) and if I ever need one a IF sweeper, but I could probably build one of those as well.
Forget the 8640, I know, I used to fix/cal them.
be prepared to fix old test gear due to age. I had to fix the 8656B Am modulator ckt, the 10 bit dac, mc3410 failed, yet another obsolete part, but I was lucky to have one on hand.
Since then I bought a spares unit.
One day I was using the 8656B and the levels were screwed up, so I went looking, can you believe it was bad solder joint on one the attenuator units, boy was I lucky, as an attenuator unit is a PITA to service or find a replacement.
I think I paid around $300-400 for my good 8656B unit and
$100 for the spares unit, it cost $100 too ship from Israel.
I was lucky to scoop the service manuals when I worked at Motorola years ago but you can get the SM from Agilent, the schematics are not so good. Quiet the beast, this old TE is a great deal, the 8656B cost around $10K new in the 80's.
Good luck
Rick
Forget the 8640, I know, I used to fix/cal them.
be prepared to fix old test gear due to age. I had to fix the 8656B Am modulator ckt, the 10 bit dac, mc3410 failed, yet another obsolete part, but I was lucky to have one on hand.
Since then I bought a spares unit.
One day I was using the 8656B and the levels were screwed up, so I went looking, can you believe it was bad solder joint on one the attenuator units, boy was I lucky, as an attenuator unit is a PITA to service or find a replacement.
I think I paid around $300-400 for my good 8656B unit and
$100 for the spares unit, it cost $100 too ship from Israel.
I was lucky to scoop the service manuals when I worked at Motorola years ago but you can get the SM from Agilent, the schematics are not so good. Quiet the beast, this old TE is a great deal, the 8656B cost around $10K new in the 80's.
Good luck
Rick
