On 12/1/19 2:29 PM, Ralph Mowery wrote:
In article ,
says...

On the HP schematic notes what was the VOM loading factor? Back in the
day 100K Ohms/volt (analog meter) was not unusual so your
"over-voltages" may simply be the result of under-loading the circuit
with your modern DVM.




On some of the old vacuum tube circuits I have seen schematics with
several voltages at test points and a note as to a 20,000 ohm/volt or a
VTVM is being used for the test.

Probably won't see much of that any more as with the solid state most
resistances are low enough an analog meter will not load it enough and
most are using digital meters to do the testing.


Those were almost always grid voltages.
Those DID require a high resistance volt meter to not load them down.
The other voltages in the set, plate, screen filamant were not that
critical about loading.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com