lsmith wrote:
>
> Hello all:
>
> First post here. Newbie on 160, and want to do things right the first
> time (or at least avoid making some very time consuming bone-head
> moves).
>
> I have been reading "Low Band DX'ing" and want to put up a couple of
> beverages for use on 160 and 80, but can't seem to find a source for the
> Indiana General torroids which John recommends. Can anyone send me in
> the right direction for a supplier?
>
> Also, can you recommend another book or general reference material
> applicable to Beverage antennae. I understand there was an excellent
> booklet published by the FCC many years ago regarding the use of
> Beverages at broadcast stations as a part of the CONELAD program. Would
> gladly pay for copying costs if you could help me out. Thanks in
> advance for the opportunity to learn a few key points from you fellows.
> My limited experience on 160 last winter has me convinced that it truly
> is a "Gentleman's Band" and the quality of QSO reminds me of what I used
> to hear on 20 metres about 30 years ago. 73 de
> J. Lee Smith,
> VE4ANC,
> 110 Senecal Drive,
> St. Francois Xavier,
> Manitoba,
> Canada
> R4L 1A9
>
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The AMIDON FT-114-75 works perfectly for 9:1 beverage transformers.Use
ON4UN's Table 7-3 (page 7-13) for winding details. Ref.#4 in Table 7-4 is
a misprint and should read FT-114-75 not as printed FT-144-75 (no such
animal). If you have a Autek RF Analyst or MFJ antenna analyzer just
attach a 500 (+ or - 50 ohms)resistor to the output of the transformer
and the analyzer to the 50 ohms winding and you should read darned close
to a 1:1 match. Be sure to use noninductive resistors for the
termination. You can make them using parallel/series out of carbon 1 watt
resistors. Don't worry about exact tolerances, 450 - 550 final resistance
is fine. Don't use potentiometers of any kind for the termination. It is
guaranteed that if your the power from your transmitting antenna does'nt
burn them out close lighting strikes will!
I use 1/2 wave beverages(250') long up 10-12' and they work great. I
even have a neighbor with an electric frence within 20' of one end
termination and listening on an opposite direction beverage it doesn't
bother me. The one thats' 20' away is of course another story. Luckily
the neighbor moves the horses for the winter and turns off the fence. Of
course if you can go 1 wave length or better, do it.
If you have that antenna analyzer, the final SWR on a 1/2 wave is
1.5-1.7:1 while a full wave will be close to 1:1. Mine are 1:1 on 80
meters.
I hope this helps. Good luck and see you on topband..
73's Ralph, W1ZK
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