As an added note: On the Beverage with the bad transformer also had a blown
termination.
Chuck W5PR
----- Original Message -----
From: "Chuck" <w5pr@swbell.net>
To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Sent: Sunday, February 28, 2010 12:46 PM
Subject: Re: [TowerTalk] Beverage Antenna Problem-Long-Final Results
> As a follow up to my emails about the troubles with 2 of my Beverage
> antennas: I found that one of them had an old connection between the
> beverage box and the antenna that had been covered with liquid tape and
> had
> deteriorated under the tape. Making a good connection to the antenna
> solved
> that one.
>
> The second was not so easy. Resistance measurements were normal and I
> traded out the transformer with a used one to no avail. (I decided not to
> take a working transformer out of a working Beverage so close to the
> contest.) I dragged the box and coax into the shack. I put a 75 ohm
> resister across the coax and had good SWR transmitting 1 watt into the
> feed
> line. OK, the coax is good. Then I put a 470 ohm resister across the
> output of the Beverage transformer (after reinserting it) and the SWR was
> bad. I then decided the core had become degraded somehow and it (and the
> other one I tried) were bad. I don't know how or why, but they were.
> Dave,
> K1TTT warned me about this so I put out an emergency message to find a new
> transformer or a core to wind one to no avail. It was the day before the
> CQ
> 160 contest, so I did not have any time to spare. I looked through my
> huge
> amount of stuff collected in my 53 years (and I am not even that old!) of
> ham radio and found an Amidon 150 core. I discovered it was close to the
> right permeability and ran to the "Shack" to get some #20 and #22 hookup
> wire. I was astounded that the young lady who greeted me actually knew
> what
> it was and how to find it, so I was off in a hurry. I had some glass cloth
> tape and I wound my first "UNUN" according to Jerry Sevick's formula and
> now
> have a 100 watt transformer with low SWR in my NW Beverage! I felt great
> that my first try at winding an UNUN worked and also that all 4 of my
> (albeit short) Beverages was working. (Now I am thinking about putting the
> 2000 watt rhombic terminating load I collected from who-knows-where on the
> end of a Beverage and transmitting into it... Hummmm)
>
> Anyway, I got everything working before the contest, but I have some noise
> source that kept the meter over S-9 all the time on the vertical transmit
> antenna. Since I am on a small piece of property, it was transferred to
> the
> beverages. The northeast beverage was the least affected luckily, so I
> heard about 25 strong Europeans. I was surprised the Europeans were so
> easy
> to copy and the stateside guys were, many times, much weaker. I never was
> able to copy any station on the vertical all weekend. The SE Beverage was
> the noisest by far. I think I transferred the noise from the power line
> close to the end of the SE Beverage to the vertical where the Beverage
> passes close to the end of one of the elevated radials. Then the vertical
> reradiated the noise.
>
> It kind of reminded me of the first year I made a huge ground plane for
> 160
> by converting the 160 inverted V to radials and flying a plastic helium
> balloon shaped like a wing to hold up the vertical portion of the antenna.
> I attached the balloon about 3 feet above the top of the vertical and the
> static charging was huge and made a terrible noise on receive. What an
> alligator I was! The next year, I put about 20 feet of nylon line
> separation between the antenna and the balloon and it worked ok. (But not
> as good as one would think.)
>
> The weekend before during ARRL CW, I worked 29 Europeans on the vertical.
> I
> noticed the noise then, but it went away before the contest.
>
> By the way, I found that power tool battery chargers left plugged in with
> no
> battery inserted can be a significant source of noise that sounds like an
> electric fence charger.
>
> Thanks everyone for the suggestions and the contacts on 160. I think I
> will
> go single band 10 meters next weekend. Hi
>
> Chuck W5PR
> ----- Original Message -----
> From: "K1TTT" <K1TTT@ARRL.NET>
> To: "'Tower and HF antenna construction topics.'"
> <towertalk@contesting.com>
> Sent: Thursday, February 25, 2010 6:16 AM
> Subject: Re: [TowerTalk] Beverage Antenna Problem
>
>
>> It can definitely be the transformer. Just had one go bad here either
>> from
>> lightning or moisture that corroded the connection, can't tell for sure.
>> Compare resistance readings to the working one or trade them and see if
>> the
>> problem moves.
>>
>>
>> David Robbins K1TTT
>> e-mail: mailto:k1ttt@arrl.net
>> web: http://www.k1ttt.net
>> AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
>>
>>
>>> -----Original Message-----
>>> From: Chuck [mailto:w5pr@swbell.net]
>>> Sent: Thursday, February 25, 2010 03:02
>>> To: tdxs-list@tdxs.net; Tower and HF antenna construction topics.
>>> Subject: [TowerTalk] Beverage Antenna Problem
>>>
>>> I have been trying to repair my 4 beverage antennas. Wires and
>>> terminations are good. 2 of the beverages work well, 2 are "dead" I
>>> have
>>> checked the coax and connectors are ok. Other than broken wires, what
>>> can
>>> go wrong with the transformer? What the heck am I missing? Short to
>>> the
>>> core? I will try moving a transformer from a working Beverage to a dead
>>> one to see if that is the problem. Both "dead" ones have RG-59 coax
>>> with
>>> foil and shield to them. The working ones have other types of coax. All
>>> have transformers from ON4UN that used to work great. 3 are 600' one is
>>> 800' the 800' and one 600' are not working.
>>>
>>> I guess I should try the substitution of another transformer first...
>>>
>>> Thanks
>>>
>>> Chuck W5PR
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
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>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>> _______________________________________________
>>
>>
>>
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