[Test-Equipment] HP 403B pegging meters

[Ron Youvan]

>  Here's my best guess as to what's happening.  There's a big 
> 1200 microfarad de-coupling cap in the DC negative feedback loop.
 >  This is probably necessary in order to get the frequency response
 > down to 5 Hz. Until it charges up (through an 8.2K resistor ) and
 > the loop can correct itself, theres an > initial rush of current
 > through the meter movement. I still can't account for the second
 > 'peg', though.

>  It would be interesting to know if anybody has devised a way to 
 > prevent the pegging. Perhaps using some component or trick that
 > wasn't available back when the instrument was designed?

   Disabling the "meter amplifier" (or shorting out the meter)
until a slower capacitor is charged is trivial, but that option
was available to the original designer.
-- 
    Ron  KA4INM - Please pay your taxes promptly our
                  illegal aliens need the free benefits!