ON7YD wrote:
I can confirm that G3XDV is about 6dB stronger than some weeks ago,
whatever you did Mike it was worth it (and if it is not a new PA I curious
what you changed).
Thanks Rik for the report. I made two changes: I raised the far end
of the antenna from 9m to about 15m, and I got more RF out of the
pa by foced-air cooling it (standing a fan heater next to it!!).
I have two improvements scheduled: at present the top horizonatl
section droops by about 2m in the middle becuase one mast is
flexible fibreglass. An aluminium mast will allow me to increase the
tension on the wire and reduce the droop. It will also allow two top
wires instead of one. I also have plans for about 3dB more power.
Both of these require time which is in short supply at present.
Hope to be a bigger sig by next winter.
Most puzling was the signal of G3YMC, during his QSO with G3XDV he came all
the sudden 'out of nothing', was 429 here for a few minutes and disapeared
again.
I think this is the 3rd time I noticed this fenomena on his signal.
I have noticed that stations using loop antennas on transmit (I think
that is only G3YMC, G2AJV and sometimes GW4ALG) can have
much more QSB at a distance of a few hundred km than those
using Marconis. This QSB is quite rapid, a minute or two - whereas
the QSB on DCF (138.82) is very slow indeed, often an hour or
more from peak to trough. I presume this means that there is a
large amount of RF going straight upwards from a loop, so there is
more ionospheric interference over a short distance.
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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