开云体育

I took some time to measure the actual performance of my uBitx with its original calibration against a dummy load. The instruments used are not lab calibrated. I did check my wattmeter against my recently factory calibrated K3 and found the power reported to be about 5% high. The power supply is rated as 25 amps and set at 13.7 volts. I tested by simply pressing the PTT (no audio input, power out 0) and keying CW.
Receive current: .25 A

?	PTT	CW	CW
f kHz	I amp	I amp	P watt
3,530	0.74	1.8	8
3,970	0.74	2.1	9
7,030	0.73	1.57	5
7,270	0.7	1.6	5
10,113	0.72	1.22	3
14,030	0.71	1.34	3
14,320	0.71	1.37	3
21,170	0.69	0.96	1
28,900	0.69	0.83	0.5

The results agreed in general with Dave's (WI6R) post /g/BITX20/message/39578, although his results start a bit higher and end even lower.
Although my current draw with PTT down agrees with the value specified on the Tune-up page, I never quite see 10 watts out. The 80 meter power isn't too bad, but the 14 MHz is half and 28 MHz is 1/4 of that mentioned on the uBitx web page.

What TX performance have others seen?
Any fixes for higher frequencies?

???? Bob?? KD8CGH