Hi Rick...didja get stuffed yesterday?
This is currently just a recieving antenna, but found my configuration just
worked out to resonance on 3.60 mhz.
I am using a few buried radials....most of my extensive radial field from a
past ground mounted vertical is glitch...new bedroom/bath construction sits
on the site. Will bury some new ones this spring or next fall.
Usually I use a 4 to 1 or 1 to 1 voltage balun....just to dump noise and
static to ground. I am not too concerned about matching at this time since
the station is going to be moved into another room in a couple of months,
and I will be busy running coaxal and 600 ohm feeders inside the old wooden
walls, etc.
To my thinking, signal to noise should be much improved but it got a lot
worse.
----- Original Message -----
From: "Rick, NJ0IP / DJ0IP" <Rick@DJ0IP.de>
To: "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Sent: Friday, November 23, 2007 7:36 AM
Subject: Re: [TenTec] balun noise?
> Hi Denton,
>
> Not sure why you are experiencing that, but more important, why are you
> even
> trying to work with a balun? This is an unbalanced antenna.
>
> I suggest you follow the design of the 160m version which Scott, W4PA,
> published many years ago - just build it half size.
>
> - Make the vertical section as long as possible, and the overall length
> about 75 to 80 ft.
> - Cut the radials to a quarter wavelength.
> - Insert a small variable capacitor between the antenna and the center
> conductor of the coax (at the feed point). 500 pF should suffice.
> Probably
> less.
> - Tune the variable C for lowest SWR at resonance (should easily be below
> 1.5:1 - mine went to 1.1:1)
> - Replace the variable C with a fixed C that is capable of handling the
> high
> voltage. For this I used a fixed C slightly lower than the required
> amount
> and then used a piece of RG-213 soldered in parallel to the fixed C to
> provide the rest. Cut this piece of coax longer than needed and prune to
> the desired length (such that you have best SWR again).
>
> I would recommend inserting an RF choke in the coax at the feed point,
> either by coiling some coax to make the choke, or use one of the many
> commercially available ones (source: Radio Works, MFJ, etc.).
>
> I ran this last year on 160m during CQWW CW and it out-performed all other
> antennas I had previously built (on my property) by a significant amount.
> I
> basically worked everything there was to be worked on that band (following
> the cluster) with just 500w, and most was worked on the first or second
> call. When calling CQ I even had transatlantic answers. (Call sign was
> DJ2T last year).
>
> Good luck in the contest this weekend.
> Unfortunately I don't have much time this weekend due to a death in the
> family, but I will be on in the evenings.
>
> 73
> Rick, NJ0IP / DJ0IP
>
> -----Original Message-----
> From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
> On Behalf Of Denton
> Sent: Friday, November 23, 2007 1:19 AM
> To: Discussion of Ten-Tec Equipment
> Subject: [TenTec] balun noise?
>
> Not really a ten tec question...but this little group seems to be
> particularly knowledgable...
> I am tinkering with an 80 meter inverted L antenna, and I noticed that
> when
> I hook up any kind of balun at the feedpoint, the signal to noise is much
> more prevalent than when feeding the L directly with coax.
> The L has a few radials attached and shares a common ground rod with the
> radio station ground.
> Wonder whythe worse signal to noise. Thanks...
>
>
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