The Palomar wattmeter shown in the first post has a hidden "easter egg" peak-reading feature.
As in sorta peak reading. With the left switch on Power, flip the Forward/Reflected switch to Reflected. This connects a capacitor to the meter's coil circuit. The capacitor serves to hold the voltage that it's charged up to by your voice peaks, and then discharge into the meter coil to keep it from falling during the "valleys" between the peaks in your voice waveform.
This method works, and it's called a "passive" peak-reading meter.
Except there's nothing printed on or in the meter that says "peak".
Nothing.
One side effect of a "passive" peak-reading circuit is that it will be stingy on the meter's lowest-power watt range. And for a max scale wattage of 200 or more this method can be 90 or 95% of what a lab-grade peak meter would show you.
The lab-grade, or expensive ham-grade meter uses what's called "active" peak reading. What this means is that we still charge up a capacitor with your voice peaks. But we slow down that capacitor's bleed-off rate using a current amplifier to drive the meter coil. The voltage going to the meter's coil doesn't change, but the current to hold the pointer up during those valleys comes from a current-amplifier circuit. And from the power supply that runs it.
And that's what divides the active solution from the passive. It needs a source of DC power.
Odds are that the Palomar 500 meter in the pic above will let you tune up your stuff, even if it isn't exactly lab accurate.
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