Slightly OT manual request

[Jim Strohm]

Hi all

I need a manual for an HP power supply that doesn't glow in the dark, but
would help with equipment that does -- and qualifies in all other respects
as a boatanchor.

It's an HP 6521A supply, 0 - 1000 V, 0 - 1 A.  I need a schematic or
manual, and it does not need to be for this exact model.  This one is one
of the line-side regulated supplies (as opposed to the conventional
output-regulated type), and I need a Clue about how they work so I can (try
to) fix mine.

Reasonable copying costs paid, or will trade manual copies.  I have:

HP 8690A sweeper mainframe Operating and Service manual
HP 8691B, -1D, -2B, -3B -4B sweeper plug-in Operating and Service manual
11531A Calibrator for HP 8690A sweeper Operating and Service manual
HP 5245L frequency counter Operating and Service manual
HP 5253B frequency converter Operating and Service manual
HP 312A Wave Analyzer (frequency selective voltmeter) Operating and Service
manual
HP 3200 VHF oscillator (also on BAMA)

and a few more.

Thanks...

Jim N6OTQ