There is no input coil on that matchbox.
It uses a symmetrical "T-Filter" and has an input capacitor.
Besides, it is not as good to try to compensate for the high impedance
inside the matchbox, as it is to change the impedance of the antenna system
by a simple adjustment of the feedline length (1/8 wavelength {electrical}
longer).
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Denton
Sent: Sunday, February 13, 2011 10:35 PM
To: geraldj@weather.net; Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Antenna follow up- asked for help in January- need
more help.....
I use a horizontal loop..about 235 ft in length.
My current matchbox has an adjustable tap on the input coil. With a little
tinkering with the input tap, feedline length, feedline width, I have gotten
my matchbox to work 80 thru 10 meters, WARC bands and 60 meters (if 2.25 to
1 swr is acceptable on 60 meters)included.
Quite a bit of work....but to me it was all worth it.
----- Original Message -----
From: "Dr. Gerald N. Johnson" <geraldj@weather.net>
To: <tentec@contesting.com>
Sent: Sunday, February 13, 2011 6:00 PM
Subject: Re: [TenTec] Antenna follow up- asked for help in January- need
more help.....
> That is an effective but sometimes inconvenient way to handle an antenna
> and feedline that gets the feed Z out of the range of the tuner, a
> significant problem with the limited range of the Johnson Matchbox.
>
> 73, Jerry, K0CQ
>
> On 2/13/2011 7:49 PM, Ken Brown wrote:
>> I have a center fed dipole, fed with 450 ohm ladder line. I built it to
>> the dimensions that were convenient, without much regard to how the
>> dimensions relate to a wavelength on any particular band. On the bands
>> that my Johnson KW Matchbox can tune it, with the shortest length of
>> ladder line from the feed through the wall to the Matchbox, I operate it
>> that way. On the bands that it cannot tune it that way, I add lengths of
>> ladder line, until I find a length that allows the Matchbox to tune it.
>>
>> Not quite as convenient as if only changes in the tuner knobs were
>> needed to change bands. It works though.
>>
>> DE N6KB
>>
> _______________________________________________
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> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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