de 4S7RPG
Having taken delivery of some Toroids from a famous supplier who is on the
reflector I now have the beverage working much better than earlier. It is
bidirectional, 300ft long and pointing 300/120.
However at first results appeared a little disappointing but on reflection
(! sorry) understandable. Some signals were equal strength on beverage as
on the vertical. There was some directivity on the beverage and strengths
were not so low as to warrant any need for a preamp.
Static crashes were down from S9 to an S7. I was surprised since I thought
it would reduce the static levels more. Listening to YC0LOW he appeared
stronger on the beverage than the vertical.
All this may seem a bit contrary to theory but two ponts to note.
I use a TS430 and you cannot switch the AGC off. Consequently when
receiving on the vertical the levels of static keep the AGC backed off
resulting in a signal which appears weaker signal on the vertical than on
the beverage you cannot always go by the S meter since the signal is less
than the static. The resulting Sig to Noise is better.
Secondly while I thought the static on the beverage would be lower than what
I am getting (ie the improvement in Sig/Noise is not as good as hoped) it is
not surprising since the beverage goes through dense undergrowth past tall
trees etc. I presume that there is pickup from this vegetation that is
inducing vertically polarised signals on to the beverage.
Anyhow food for thought for those passing wires through forests or no mans land.
73s
Bob Parkes
Sorry for the taking up so much memory but had to do something useful with
the time as the curfew has been extended from 8.00am to 2.00pm and I cannot
get into the office to finish off the work!!
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