No, this balanced link matchbox was limited in its matching range and could
definitely NOT match just about anything.
Time and again we saw that at field day when using a Johnson Viking Matchbox
275w with two different openwire fed antennas.
Often we had to play with feedline lengths to get them to work on all bands,
but when I substituted my MFJ-974B for the Viking, we could get a good SWR on
all bands without having to adjust the feedline length.
The JVM was limited in matching range.
The downside is, the MJF has a lot more loss than the JVM.
So in each case we chose the lazy way out and simply used the MFJ.
The correct answer (and procedure) is to read the information on my web site
about the JVM and think about what I have written. It will be apparent why the
JVM has limited matching range.
THEN follow my guidelines to modify your JVM and it will have the matching
range we need and THEN it becomes the best matchbox ever - because then it
becomes an ANNECKE - which is the best matchbox ever made.
Cheers!
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Gary J
FollettDukes HiFi
Sent: Saturday, July 16, 2016 7:51 PM
To: - -
Cc: Discussion of Ten-Tec Equipment; Scott Harwood
Subject: Re: [TenTec] OT: Question to the group
Not “wrong”, just dated a bit in regards to WARC band operation.
The balanced link matchbox design could match just about anything. It was not
terribly lossy and it was easy to use.
I have used them with solid state radios and they work beautifully on the bands
for which they were intended - far better than the autotuners.
I did not intend to give the notion that it was perfect. However, for a
balanced line tuner, it was better than what is commercially available today,
IMHO.
Improvement is always welcome though…
Gary
> On Jul 16, 2016, at 11:29 AM, - - <rick@dj0ip.de> wrote:
>
> Sorry Gary but you're wrong about the Johnson V Matchbox.
>
> It was a long ways from being the best matchbox ever. It had a couple of
> deficiencies which back in the days of no WARC bands and tube radios with
> Pi-Networks, didn't make much difference.
>
> 25 years later its deficiencies were very apparent.
>
> On my web site I explain that in detail and show people how to modify their
> JV Matchbox to bring it up into the modern times.
>
> See:
> http://www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/viking-v
> s-annecke/
> <http://www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/viking-
> vs-annecke/>
>
> See:
> http://www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/j-viking
> -upgrade/
> <http://www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/j-vikin
> g-upgrade/>
>
> Several people have successfully modified their JVM using my instructions and
> all are much happier campers now that the dificiencies have been fixed.
>
> 73
>
> Rick,DJ0IP
>
>
>
>
>
>> Gary J FollettDukes HiFi <dukeshifi@comcast.net> hat am 16. Juli 2016 um
>> 04:31 geschrieben:
>>
>>
>> The old EF Johnson Matchbox, both the 275 watt and the 1 KW version were
>> truly balanced output.
>>
>> That was the very best tuner design ever. The actual matching coil was the
>> balun.
>>
>> Virtually every other tuner uses an unbalanced tuning system and then uses a
>> BALUN too couple to balanced feed lines. Therefore, no BALUN is, of course,
>> needed at the antenna.
>>
>> I used 600 ohm balanced line once to feed a cubical quad (Gem quad) and it
>> worked extremely well.
>>
>> Oh, I too always wonder why folks fret so much when they only get 90 watts
>> output instead of 100. no one anywhere can hear the difference between 90
>> and 100 watts, not even in a head-to-head shout down. Turn it down to 50
>> watts, use half the electricity and the listener will barely tell the
>> difference on the other end.
>>
>> Gary
>>
>> W0DVN
>>
>>
>>> On Jul 15, 2016, at 5:59 PM, Jim Allen <jim.allen@longhornband.net> wrote:
>>>
>>> I had one of those, not at 60', about half that. CC&Rs and all that.
>>>
>>> What is a "well designed truly balanced antenna tuner?" From what I've
>>> read, there aren't many. I have an MFJ 974HB. There is the Palstar whatever
>>> the latest model nomenclature is. Rick has the whole run down on his
>>> extensive website.
>>>
>>> What is good at lower heights?
>>>
>>> 73 de W6OGC Jim Allen
>>>
>>> Sent from my iPad
>>>
>> >> On Jul 15, 2016, at 17:28, Scott Harwood <scotthsr@earthlink.net>
>> >> wrote:>> Well, for 80 - 10 meters, how about a 135 foot wire dipole up
>> >> about 60 feet fed with 600 ohm open wire line into a well designed truly
>> >> balanced antenna tuner located right at the transceiver, as one example?
>> >>
>> >> Scott K4VWK
>> >>
>> >>
>> >> -----Original Message-----
>> >>> From: Jim Allen <jim.allen@longhornband.net>
>> >>> Sent: Jul 15, 2016 5:53 PM
>> >>> To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
>> >>> Subject: Re: [TenTec] OT: Question to the group
>> >>>
>> >>> What is "a low-loss matching and feed system into an efficient antenna?"
>> >>>
>> >>> This is the "Holy Grail" of amateur radio, if we can find it.
>> >>>
>> >>> 73 de W6OGC Jim Allen
>> >>>
>> >>> Sent from my iPad
>> >>>
>> >>>> On Jul 15, 2016, at 16:05, cegtv1 via TenTec <tentec@contesting.com>
>> >>>> wrote:
>> >>>>
>> >>>> a low-loss matching and feed system into an efficient antenna
>> >>> _______________________________________________
>> >>> TenTec mailing list
>> >>> TenTec@contesting.com
>> >>> http://lists.contesting.com/mailman/listinfo/tentec
>> >>
>> >> _______________________________________________
>> >> TenTec mailing list
>> >> TenTec@contesting.com
>> >> http://lists.contesting.com/mailman/listinfo/tentec
>>
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