7 Aug
2002
7 Aug
'02
1 p.m.
Joe wrote:
I picked up an intersting gadget today. It's a model 5203C Memory Voltmeter made by
Micro Instruments. It has a four digit Nixie tube display and appears capture and display
+ or - DC or AC peak voltages. Does anyone know anything about these? It has two zero
adjustments, among other things I'm trying to figure out exactly what they do. Neither
of them seems to "zero" the meter in the normal manner.
Does it affect the readings as you change the zero setting?
After all these years, perhaps the components have drifted
out of tolerance far enough that it doesn't zero anymore?
Also what does "Narrow band" and "wide
Band" mean? Changing the setting doesn't change the voltage range so has to be
for something else.
A guess, but a pretty safe one, would be that the AC mode
response might extend up quite a ways and the "narrow-band"
setting is to limit its sensitivity to AC noise for
measuring slow-moving AC voltages like powerline AC volts.
The "wideband" setting would presumably be chosen to read
AC voltages from at least low audio range up to who knows
how high up. Might be useful for measuring the output of
an AM or FM demodulator stage or measure gain when injecting
a nice audible AC sinewave signal into the stage under test?
Joe