My 2 wire Beverages are in the 500-900' range in the air and as BOG's and
are used regularly on 30 and 40M with no meaningful degradation.
However I wound all my transformers based upon the high RF ground resistance
here and subtracted that from the theoretical book values for the antenna.
It could be possible that the commercial transformers are providing a "suck
out" . Try tuning well on both sides of 40M and see if this is a gradual or
sudden thing.
Carl
KM1H
----- Original Message -----
From: "Herb Schoenbohm" <herbs@vitelcom.net>
To: "Niko Safaric" <niko.safaric@bit.si>; "TopBand List"
<topband@contesting.com>
Sent: Tuesday, May 22, 2012 8:39 AM
Subject: Topband: Two wire Beverage Question
Thhanks Niko for sharing your experience with me. I did not find a
reason why this takes place so I ran a separate 600 foot Beverage about
50 feet away and parallel to the two wire. The single wire works fine on
40 meters to the direction of the termination. A possible reason why the
two WD1-A does not work in the reverse direction on 40 meters, but works
well on 160 and 80 could be that it is to long for 40. This is just a
gut reaction as I have not come up with any reason.
I hope someone of the topband list group here has an answer.
Herb Schoenbohm, KV4FZ
On 5/22/2012 5:02 AM, Niko Safaric wrote:
>
> Dear Herb,
>
> On topband contesting Ihavefound your question about strange manner of
> your beverage
>
> »I have a 900 foot WD1-A two wire Beverage that runs east and west
> and
>
> works well and has a great FB ratio on 160 and 80 meters. It is
> fed with
>
> a KD9SV box and reflection transformer for WD1-A telephone wire. I
> have
>
> swept the antenna with an analyzer and the antenna is relatively flat
>
> beyond 10 Mhz. However I notice that when I try to RX with it on
> 7Mhz
>
> the reception (noise level) drops to the floor and signals are not
> there
>
> in the West direction (Reverse Direction) but OK in the East. The
> noise
>
> floor drops a good 30 db and the receiver appears dead on 40 to
> the west
>
> but works well to the East. I have an identical WD1-A two wire
> Beverage
>
> running NNE and SSW which works fine on 40 meters in both
> directions. I
>
> have absolutely no idea why this should be the case except that the
>
> cable feeding the Beverage box is RG-6U and could have some water
>
> encroachment which increase the losses at 7MHz greatly. Before I
> do a
>
> new cable run I plan to just swap the two RG-6 cables and see if the
>
> problem reverses now to the East rather than the West. I post
> this to
>
> ask if anyone has had a similar experience with a well functioning
>
> Beverage that appears completely dead on 7 Mhz and above.«
>
> I have exactly the same problemas you hadexceptmy beverageis not
> completedeadin one directionon40mand higherbands.F/B ratio
> isalsostrange.With switching directions W/EI cangetup
> to30dBF/B,butonly for signals coming from East.On another
> directionF/Bratio issignificantjust for some signals coming from W,
> but not for allof them.
>
> I havealreadyreplacedtransformers, made a good ground with radials on
> both side, replacecoax RG59 with RG213...butnodifference.
>
> I am interested, how did you solve your problem?
>
> Best regards,
> Niko, S53a, 9J3a
>
>
>
>
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