About:
"I have an RF probe made per ARRL hand book with a 1N34A diode which is
good to about 20 volts. I use it for alignments and such. With 20
volts
RF into a 50 ohm load I have 8 watts carrier out. This is pretty close
with what I have on the watt meters as well but too low to calibrate
from. Can I put 10 of these diodes in series and run the RF volts to 200
volts and expect to get 80 watts on the watt meter? Is this an accurate
way to calibrate an RF watt meter or is there a better way?"
I think there is an improved (accuracy) way. You can use a 6AL5 tube
with its heater tied to its cathode, and its two plates connected in
parallel. This configuration allows for a full legal power rating. Use
two caps in the filter, one for RF and the other bigger one for a
holding factor. Measure the DC voltage output with a VOM or VTVM, and
convert the reading to RF watts using the standard peak voltage formula.
Mine works great from QRP to QRO. Accuracy depends on your meter,
typically 2-percent, etc.
73, Roy K6XK Iowa Outback
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