[Heath] Fixing Heath Tube transmitters with an HP-410B VTVM

[Robert Myers]

I acquired a supposedly completely recalibrated HP-410B VTVM off eBay to use
on realigning my SB-401/SB-303 pair and other Heathkit gear.  It turns out
that it was far from calibrated.
	
I redid the calibration (going right from the manual) for the first three
(selectable) low full scale readings of 1 Vrms, 3 Vrms, and 10 Vrms. [The
scales show RMS values that are actually derived from the peak values of
sine waves as detected by the RF probe.]  I did this using a modern
precision Agilent signal generator to generate the input signals at the RF
probe.  The problem is the generator's maximum sine wave output is about 3.5
volts RMS.

Is there an easy way to do the calibration on the higher RF scales of 30V,
100V, and 300V RMS?  I don't have a test instrument to generate these values
at such a high level.

Any suggestions?

Cheers,
-- Rob Myers, Ottawa
VE3JQL