Gerry, he said it was a MFJ-974, which I also own, and am very familiar
with.
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Dr. Gerald N. Johnson
Sent: Monday, February 14, 2011 11:07 AM
To: Rick - NJ0IP / DJ0IP
Cc: 'Discussion of Ten-Tec Equipment'
Subject: Re: [TenTec] Antenna follow up- asked for help in January- need
more help.....
How do you KNOW "that matchbox" has no coil to tap? If its a Viking
Matchbox its a link coupled with an input coil. He didn't say what kind
of match box.
73, Jerry, K0CQ
On 2/14/2011 5:44 AM, Rick - NJ0IP / DJ0IP wrote:
> 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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>>
>
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>
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