sure!
this ones in russian so hit translate.
http://electronix.ru/forum/index.php?showtopic=86845
he ends up repairing it via the link I posted above.
and this:
http://www5a.biglobe.ne.jp/~jh2clv/ms8604a.htm
I couldn't mange to translate it so its quite useless. Looks like he has a fault and linked to a workshop manual but the link is dead.
Use google images for your search and good luck on the repair!
Well, my russian is a bit rusty, but so far as I understand the message on that forum,
he attempts to repair MS4670A, he uses MS8604A (he connected something to MS8604A),
and someone points him to that MS462X VNA maintenance manual, which is totally different machine (VNA vs SA).
But thanks anyway.
Just FYI, the MS8604A has plenty in common with MS2602, the RF section is identical, most of the digital circuity
is the same - couple of different processors communicating with each other....
Service manual for the MS2602 is in the wild, however just the volume 1...