• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Rf probe and AF voltmeter?


Not for RF you cant.Rf probe has a cap for isolation and a diode to rectify the signal. You read on the dc scale . You can be dealing with microvolts to hundreds of volts depending on what you are reading.
 
You have to look at the specifications of the particular AC voltmeter you're considering. The manufacturer probably rates it from 50 hertz to 400 hertz if it's just for measuring line frequency. Other companies make audio voltmeters that cover a much wider spectrum.

And no, you don't use a voltmeter to measure audio frequency.
 
"Soo the purpose of an AF voltmeter is to show true rms????"

only if its a true RMS reading meter,
AF volt meters could be AVG, RMS, peak, peak to peak,
some have more than one option like my old taylor 172a that measures AVG & PEAK to PEAK,

most inexpensive digital multimeters are AVG rectified for measuring AC volts & are only happy with pure sinusoidal signals,
some are true RMS reading & handle none pure signals much better,
 
  • Like
Reactions: unit_399
Most DMMs and DVMs measure AC over a very limited frequency range. Usually between 40hz and 1000hz. Above and below that range the readings fall off. So a typical DMM cannot be used to measure audio, which extends well over 10khz. I use an old Heath AV-3 VTVM for audio testing. Flat response from 10 hz to 400 khz. High input impedance doesn't load down the circuit being tested (either solid state or tube). Stable, reliable, and most importantly CHEAP.

- 399
 
  • Like
Reactions: bob85
Thanks for the reply. So when they say on the new cobra 29 ltd align procedure to hook up AF voltmeter with signal generator. What exactly are you trying to get a reading on? The old alignment use to call for just an AC voltmeter. Any help would be great.
 
Thanks for the reply. So when they say on the new cobra 29 ltd align procedure to hook up AF voltmeter with signal generator. What exactly are you trying to get a reading on? The old alignment use to call for just an AC voltmeter. Any help would be great.
Are you talking about receive alignment?
I use a SINAD meter and a signal generator for aligning receive.
 

dxChat
Help Users
  • No one is chatting at the moment.