I recently acquired this 20yo Service Monitor (1GHz Spectrum Analyser,
etc) which does not boot. I don't wish to discuss its symptoms here,
just to ask whether anyone has any service documentation for it?

I've done extensive google searches and found operations manuals, and a
few other things including a supplement for the COM-120C variant
(including a block diagram) but no schematics - IFR/Aeroflex has kept
those really tight. The BatBoard discussion list has a number of other
folk who've also looked and found nothing, but I thought perhaps it was
worth asking here.

Clifford Heath