Chris:
Slowing the signal on the wire is indeed helpful in that the antenna then
appears electrically longer and that reduces the beamwidth. That is
independent of thetermination issues you mentioned.
This technique dates all the way back to Harold Beverage himself, and you
can read a bit more about this in his 1923 papers about the Beverage
antenna.
Chuck
-----Original Message-----
From: topband-bounces@contesting.com [mailto:topband-bounces@contesting.com]
On Behalf Of Chris Zeal
Sent: Wednesday, March 10, 2004 12:24 AM
To: Topband Ref
Subject: Re: Topband: Loaded BOG Rx Antenna - 160 meters
Hi all
Thanks for the replies below from Bob and Eric to my mail of 8 March.
What do you expect that lumped inductance in the middle of the wire (or
anywhere else, for that matter) to accomplish? I can't see anything in the
theory of that antenna, which is somewhat limited, that hints at this.
What is the purpose of the loading? Slowing the signal on the wire is not
helpful. Termination value changes with weather conditions, ground
characteristics.
200 ohms is a fair average value (for resistor itself). 20 ohms is certainly
too low unless the ground connection itself is in the range of 200
Both points are noted and appreciated. I am not in a position to argue
technically. However my aim was to compensate for the shortened length of
BOG while accepting additional signal loss. If loading is not worthwhile
where does this leave the 'slinky' type system?
Incidentally the ground here is very poor and probably does account for the
high resistance earth connection. I am feeding via a 1:9 transformer (I
tried a 1:4 first).
I shall carry on with the experimentation.
Regards, Chris G4BGM
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