In article ,
Theo Markettos wrote:

I'm reading the calibration section of the service manual for a spectrum
analyser, and that tells me to connect the IF output to a 'selective level
meter'. I've had a google and can find lots of (mostly antique) models, but
I can't seem to find anything that describes what one of these is.

Am I right in guessing it's essentially a narrowband AM receiver with a
power meter for the carrier? So a spectrum analyser with only one
horizontal point? Are they typically more accurate than a spectrum analyser
- or can I just use another analyser?

Theo-

I expect a frequency selective voltmeter will have an accuracy in the
order of 5% (1/2 dB) or 10% (1 dB) of its full scale reading. The
spectrum analyzer probably has an accuracy measured in dB, probably
greater than 1 dB.

I might depend on another analyzer if that was the only option. Then
the question would be whether the second analyzer is less accurate than
the one you're trying to calibrate! Somewhere along the line you need a
standard to compare with.

Fred
K4DII