Bob,
Dummy one is for the trash bin! Two things that agree is a better reference.
Raj
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At 19/12/2017, you wrote:
Second try - it posted mid typing for no discernible reason and I can't find an edit or delete
I am seeing about a 2x variation in power draw on my uBitx with different dummy loads and a well tuned antenna. Here are the results with average measurements taken over two days on 40 meters. My 25 amp power supply provides 13.75 volts. Dummy 1 was made from a kit, has a DC resistance of 50 ohms and provides a diode & cap for DVM sampling. Dummy 2 is an MFJ that measures 55 ohms which yields about a 1.1:1 SWR. The antenna is feed through a tuner that reports a 1.1:1 SWR after tuning.
Dummy 1 Dummy 2 Antenna
recv .17 .12 .11
PTT .60 .34 .32
CW 1.42 .77 .75
Sampling dummy 1 with a DVM yields 22.9 volts or about 5.4 watts.
Questions:
Why are the current draws different, particularly on receive?
Am I only getting 2.5 watts out to my antenna?
Bob
Raj vu2zap