You are a LUCKY man, Rodney.
Take it on the road, using a different feedline length each time (each new
QTH) and you will run into problems.
Here is why it is working on 160m:
Normally the impedance would be very low under that situation.
A quarter wavelength of transmission line would transform it back to high.
A quarter wavelength of openwire (assuming Wireman type) is about 208 ft.
Your 182 ft. of feedline is close enough to a quarter wavelength that it is
transforming the impedance up into the range that the tuner can match. In
fact any length between 1/8 and 3/8 wavelength is going to transform it up
higher.
Most of the time my feedline lengths have been between 50 ft. and 75 ft.
long.
That probably would not have worked.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Rodney
Sent: Sunday, September 14, 2014 4:20 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Zepp?
My Ten-Tec 238 tune my 80 double ext.zepp on all bands 160-10 with a 4-1
balun 182 ft of 400 ladder line then the 4-1 with 20ft of coax.
-----Original Message-----
From: Bob McGraw - K4TAX
Sent: Saturday, September 13, 2014 9:59 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Zepp?
Because the MFJ 929 tuner only has unbalanced outputs thus no provision for
feeding a balanced load.
73
Bob, K4TAX
----- Original Message -----
From: "Richards" <jrichards@k8jhr.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, September 13, 2014 8:36 PM
Subject: Re: [TenTec] Zepp?
> Yes.... so, I try my question again: Why does he need a balun? Why not
> just connect the tuner to the feed line and skip the balun ?
>
> Here is why I ask: The tuner will take itself off line whenever SWR
> exceeds some threshold and power exceeds 75 watts. As the inquisitor
> said, he must cycle the unit off-and-back-on to resume or restart the
> tuning function.
>
> Let's just assume for a moment the problem is NOT CMC on the window
> line... why not just remove the 4:1 balun and see what gives?
>
> I hope this is no misplaced, but a serious application of Occam's Razor
> suggests to assume no balun is needed between the device and the antenna
> elements. Why presume CMC or other problems ? Why not just remove the
> 4:1 transformer and see if it tunes without it?
>
> That worked in my case. Less is more, sometimes.
>
> Any traction? Now where is my Teflon suit... ;-) ;-)
>
> ----------------------------- K8JHR ----------------------------
>
>
>
>
> On 9/13/2014 9:13 PM, Bob McGraw - K4TAX wrote:
>> My take is to bring the balanced line all the way inside to the tuner.
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>
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