Why would one need an "antenna farm" with an ERP (EIRP ?) limit of 0.1 Watt?
Even a small backyard antenna such as a 8 m high and 8 m topload
T-antenna has a radiation resistance of about 0.15 Ohm.
Taking into account a gain of 2.63 dBd (4.78 dBi) the antennacurrent
needed for 0.1 W ERP is only 0.6 A and for 0.1 W EIRP even only 0.47 A.
Assuming a loss resistance of 40 Ohm the required TX power is 15 W
(for 0.1 W ERP) or 9 W (for 0.1 W EIRP).
So there is no advantage using big antennas , except that you will
need only 1 W TX power instead of 15 W. At least if you stick to the
0.1 W ERP limit.
On the other hand using narrowband modes will give easily give a 5 to
10 dB improvement of CW.
73, Rik ON7YD
Quoting hamilton mal <[email protected]>:
Hi All
There is no need to use QRS to be heard/seen around EU. Uk stns have been
heard around EU on normal CW especially after dark. GI4DPE and myself G3KEV
have been hrd in Spain/Italy and YU but to mention a few places.
Concentrate on CW and your antenna farm and avoid Lazy Mans cw.
de Mal/G3KEV
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