Concering,
"Now if instead of an anlogue meter, the Bird 43 had a digital readout
to 3 places of decimals, people would believe it implicitly, because it
would be digital......and digital read outs hide the difference between
accuracy and resolution. (etc.)"
Years back Ham Radio magazine came out with a construction article for
an accurate wattmeter which utilized a 6AL5 tube reading the actual RF
peak voltage across your 52 ohm dummy load or any coax line with unity
SWR. Rectified and filtered RF peaks are fed into a larger capacitor so
peaks could be held for reading accurately on any DC voltmeter. Accuracy
is essentially that of the voltmeter, typically 3 percent. I still use
this device as a reference standard. Or it can be left in the line
permanently. Power handling is at least 1 KW and a conversion chart was
furnished converting DC readings to RF watts.
73, Roy K6XK
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