How to measure AC voltages from stage to stage

[walters]

how to measure ac

I know how to measure DC voltages from node to node or stage to stage on a preamp amplifier

But what about using a multi-meter to measure AC voltages from component to component or node to node or stage to stage?


Preamp Tube sockets have 1-8 pins
I take my multi-meter and measure the AC voltages from each pin 1-8 on the tube


I want to measure the AC voltages of a transitor preamp circuit that has NO BYPASS capacitor VS a transitor preamp circuit with a BYPASS capacitor and compare the AC voltages, how can i do this please?

Instead of using a oscilloscope , can i use my multi-meter to measure AC voltages on the preamp volume wiper? to measure the AC voltage on the preamp volume wiper to know what the AC voltage is at?

 

[glenjoy]

mesuring preamp

I know how to measure DC voltages from node to node or stage to stage on a preamp amplifier

But what about using a multi-meter to measure AC voltages from component to component or node to node or stage to stage?


Preamp Tube sockets have 1-8 pins
I take my multi-meter and measure the AC voltages from each pin 1-8 on the tube


I want to measure the AC voltages of a transitor preamp circuit that has NO BYPASS capacitor VS a transitor preamp circuit with a BYPASS capacitor and compare the AC voltages, how can i do this please?

Instead of using a oscilloscope , can i use my multi-meter to measure AC voltages on the preamp volume wiper? to measure the AC voltage on the preamp volume wiper to know what the AC voltage is at?

I think if you will use your voltmeter, you will get the rms values.

Use the proper tool for the said application.

 

[walters]

how to messure ac impedance

Ya i know the AC voltages will be RMS when using a AC volt meter but i'm trying to figure out how to measure AC voltages on preamps tubes or transistors to know if the gains are corrects per unit so it stays more contants for each unit i measure


When measuring DC voltages on a tube or transistor preamps , the DC voltages change 10 to 20 percent.

How does the DC voltages percentage changes affect the AC voltages? and AC gains?

Does the DC voltages percentage change the AC swing and headroom?

 

[laktronics]

how to measure ac impedance

Hi,
Yes you can , but you should check on the ac input impedance ( specified as KΩ/Volt) of the meter and ensure it is high enough so as to not to load the source impedance of the preamplifier stage being measured. Normal multimetrs will have less input impedance (about 20kΩ/volt?) and may not be suitable. You may have to use VTVMs ( Vacuum Tube Voltmeter ?) or similar high impedance AC voltmeters for this purpose.
Regards,
Laktronics.

 

[faraz7777]

ac voltmeter measurement opamp

Hi !
I am happy hearing so good questions.
I confirm the previous aiding tip written by Mr/Ms. laktronics.
AND suggest you to use the voltage follower ckt instead.
It is a simple circuit built with an op-amp,that follows right voltage to the output without putting no loading to the main circuit , It's fine , not?!
THEN you can use your own digital multi-tester to measure the voltage easily.
Good Luck.