HI all.
Stefan DK7FC is doing very
interesting test using WSPR with QRP TX on MF.
So this evening, I’ll also be
testing a very very low power configuration :
- 25 milli W output
TX power (1 W and a 16 dB serial PI resistors attenuator on 50 Ohms)
;
- 25 meters tube
vertical without top hat capacitance antenna ;
- The PAR (apparent
radiated power) is about 200 microwatt.
- I just mesured with
oscilloscope the RMS HF voltage at the base of the antenna (at cold end of the
serial tuned coil). It is only 0.7 Volt !
Of
course, I think nobody can decode this low power signal on day time. I wait for
some WSPR reports to night...
73. Andy – F6CNI –
JN19QB
