Dear LF Group,
Thanks for the reports on my signals for the weekend transatlantic test. I
transmitted QRSS with 5s dots on 135.9250kHz (to avoid G0MRF's QRG),
between about 2310 and 0350 utc. The QRN was strong, but as well as G0MRF,
I could also see and hear DF6NM's DFCW signal at various times, so DX
conditions must have been reasonable.
After a rather cold, wet evening spent in the garden, I managed to put up a
temporary 13.5m high mast under the middle of my inverted L antenna - this
made it into an inverted V, 13.5m in the middle, about 8.5m and 10.5m at
the ends, and 40m long. Antenna current was 4.8A. Since I have not used the
antenna in this configuration before, I took the opportunity to do some
field strength measurements while the tests were in progress. The average
of 21 measurements came out to -0.03dBW, or 0.993W(!) ERP. Using EZNEC, I
calculated the radiation resistance at 0.033ohms, and so the ERP to be
1.4W, so the difference between measured and calculated was 1.4dB. So it is
possible to get 1W ERP with even this quite small antenna.
At the same time, In the spaces between my dots and dashes, I also got some
rough FS measurements of G0MRF's signal - David's ERP worked out to about 0.5W.
I see that my signal showed up quite well on CT1DRP's automated receiving
system - comparing this with G3NYK's DCF39 plot, there seems to be a
reasonable correspondence, with both graphs showing a deep fade between
midnight and 0100.
Cheers, Jim Moritz
73 de M0BMU
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