Quote:
Originally Posted by Sideband
Try measuring the voltage on the triode anode of an E(U)ABC80 or any other voltage amplifier that uses a high value anode load (somewhere around 220K). The impedance here is high and you'll find that a digital meter will read a higher voltage than a 20,000 ohm per volt AVO. HT rails are a much lower impedance and wont be affected by the meter load so they will show about the same as the published voltage.
Try it with a battery valve like a DAF96 where the anode load can be several megohms.
|
An interesting point..... AVO 8 on 1000V range = 20M, cheap DMM = 1M, decent DMM = 10M.
All will upset the operating voltage, but the AVO (
on that range) will have the least effect. It's not necessarily so that the DMM will be nearest to actual operating volts!