2) nope. But I was told that it uses some kind of transformer, so the block diagram in the service manual is deceptive. I furthermore heard RUMORS of the one for the 4195A working on the 4953A if you slinked around with the cables. Sadly, this is all I know - so far, all managed to elude me.
Yes, I believe the general shape of the circuit is known or can be deduced from available literature.? The best summary I have found is here:
? ?(about the 4291A RF impedance analyzer---similar vintage from the same design group in Japan)
But it would be nice to see the innards.? The difficult aspects will be those which cannot be represented in a schematic diagram.
