[TenTec] Antenna is up, but the coupler doesn't like 160 meters

[Robert Mcgraw]

The antenna at 50 ft and its present length will look more like 20 to 25
ohms on 160M    The "600" ohm feed should work OK.   The length of the
line appears to be a large part of the issue.  Change the line length by
10 to 20 ft or shorten the antenna some 10 to 15 ft on each end. 
{Someone else did a more detail analysis of the configuration and
presented detail numbers in an earlier posting.  I concur.}

I have one about this configuration being 256 ft of wire with the apex at
50 ft.  It is fed with 400 ohm window type line and it works all bands,
all frequencies 160M - 10M with the 238 tuner. There is no problem
matching this antenna.

My feed line is about 75 ft however and it did require addition of 10 ft
to zero it in on all bands.  The extra line just wanders through the
attic being supported by the roof joists.

As stated earlier, the 160M configuration is the most difficult to get
going but once done so, it works great.

73
Bob, K4TAX






> I'll give it a try when i am back on my feet.
>
> Looks like a zipper down the front me.
>
> I wonder why the thing works so good on the other bands. tunes right up.
>
> I am going to order the 470 pf doorknobs caps from the russian guy and
> install them inside the 238. seems to be an issue with high power and the
> 160 meter band
>
>
> Mike, WB8VGE
> SunLight Energy Systems
> The Heathkit Shop
> http://www.theheathkitshop.com/
> J e e p
> o|||||||o
>
> A man with one clock knows what time it is. A man with two clocks is
> never sure.
>
>
>
> On Oct 15, 2013, at 12:36 PM, Jim Brown wrote:
>
>> On 10/15/2013 8:28 AM, Mike Bryce wrote:
>>> there are two wires, one of each side, that are 131 feet long. they
>>> meet in the middle at the support and continue down 175 ish feet into
>>> the shack to a 1:1 current balun.
>>
>> The feedpoint impedance of this antenna is close to 50 ohms on 160M.
>> Feeding it with high impedance open wire line is an unnatural act! It's
>> no surprise that you can't match it.
>>
>> Replace that open wire line with 50 ohm coax and it will load nicely.
>> As to your "balun" -- those things often called a "current balun" are
>> really a common mode choke, and their most important function is to
>> keep noise picked up on the feedline from coupling to the antenna. To
>> do that, they must be AT THE ANTENNA, not at the shack.
>>
>> When you're buying coax, don't buy junk from a CB vendor at a hamfest.
>> The Wireman sells the good stuff. Same with connectors -- if it doesn't
>> say Amphenol on it, it's junk. The Wireman also sells several nice
>> center insulators.
>>
>> As to the "balun" -- see my RFI tutorial for detailed recommendations.
>> My material has been in the ARRL Handbook for several years.
>>
>> http://k9yc.com/RFI-Ham.pdf
>>
>> 73, Jim K9YC
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>
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I am a Tentec Ambassador and compensated according to the Tentec
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