If I recall correctly, that same QST article indicated that the 300-watt
MatchBox was the most efficient and well-balanced of those units tested.
The 1KW MatchBox although good, was not as efficient in its tuning and
matching function as its smaller brother. I've been using the 300-watt
transmatch for some time now and even today it's an incredibly well-built
and well-designed apparatus. However, Steve has already noted its
shortcomings; perhaps the most important being its somewhat limited tuning
range. The Matchbox was designed for reasonably-sized (even small) dipole
and long-wire antenna where multiband operation was required. It was never
meant to load-up the proverbial "bed springs." If you can find a matchbox
that has not been tampered with, I highly recommend purchasing it if you
foresee a need for a multiband antenna system. For me, I like the fact that
I only have to throw the antenna up once and never worry whether I have the
antenna tuned to perfect resonance. The desktop Matchbox handles this pain
for me.
-Paul, W9AC
-----Original Message-----
From: Steve Ellington <N4LQ@iglou.com>
To: Steve Ellington <N4LQ@iglou.com>; Sherrill WATKINS
<SEWATKINS@dgs.state.va.us>; tentec@contesting.com <tentec@contesting.com>;
reid.w.simmons@intel.com <reid.w.simmons@intel.com>; jmlowman@ix.netcom.com
<jmlowman@ix.netcom.com>
To: <tentec@contesting.com>
Date: Thursday, March 30, 2000 12:10 PM
Subject: [TenTec] Re: TenTec VS Johnson.
>
>Lest I be misunderstood. The Johnson Matchbox is at the top of the heap as
>far as LOW LOSS goes. Not LOSS. Sorry for the bad wording.
>Steve
>N4LQ
>----- Original Message -----
>From: "Steve Ellington" <N4LQ@igLou.com>
>To: "Sherrill WATKINS" <SEWATKINS@dgs.state.va.us>;
<tentec@contesting.com>;
><reid.w.simmons@intel.com>; <jmlowman@ix.netcom.com>
>Sent: Wednesday, March 29, 2000 8:00 PM
>Subject: Re: TenTec VS Johnson.
>
>
>> We all know that you can't just stick a balun on the input of a single
>ended
>> tuner like the 238. The tuner would have to be totally redesigned.
Instead
>> of only one roller inductor, you would need two if one wanted to match
the
>> same range of impedances. Fussing at TenTec because they don't just move
>the
>> balun to the input just doesn't make sense.
>>
>> Secondly. The fact that you have a wire 1/2 wave length on 80 meters fed
>> with open wire line and the Johnson tuner can match it doesn't mean that
>it
>> will work for everyone. Feeder length is just as important and some
>lengths
>> will give even the Johnson problems. I know because I've got one setting
>> right here on the shelf. Of course one can always add to remove some
>feeder
>> to bring the impedance within range of the tuner. The impedance range of
>the
>> Matchbox and the Johnson is no secret. It's published in the manuals plus
>> QST ran an extensive test on tuners a few years ago. The old Matchbox was
>> near the top of the heap as far as loss goes. The TenTec wasn't tested.
>>
>> If the 238 has some weak points it's these:
>>
>> Hard to read coil scale.
>> Dial lights burn out often.
>> Flimsy construction.
>> Crank Crank and Crank
>>
>> Good points:
>>
>> Widest matching range on the market.
>> Matches looks and construction of other TT stuff.
>>
>> Johson Matchbox Good points:
>>
>> Built like a tank
>> Balanced output with no balun loss.
>> No coil to crank and crank and crank
>> No dial lights needed.
>>
>> Johnson Bad points:
>>
>> No 160 meter coverage
>> No antenna selector switch
>> KW model is huge
>> Doesn't match looks of TT stuff. (like I care)
>> Sometimes works ok on WARC bands, maybe.
>>
>> So you may have noticed I hate to crank those inductors. That's why I'm
>> using a new Ameritron ATR-15.
>>
>> Steve
>> N4LQ
>>
>> ----- Original Message -----
>> From: "Sherrill WATKINS" <SEWATKINS@dgs.state.va.us>
>> To: <tentec@contesting.com>; <reid.w.simmons@intel.com>;
>> <jmlowman@ix.netcom.com>
>> Sent: Wednesday, March 29, 2000 1:35 PM
>> Subject: RE: [TenTec] Re: Ten Tec antenna tuners
>>
>>
>> >
>> > As I understand it, the tuner problem is not because it is a T or an L
>> network type. The problem is because the balun is feeding
>> > power into a high reflected wave (swr). Moving the balun to the input
>> corrects this problem. If Ten Tec does not do this in their
>> > most recient model, then their tuner still has the basic problem. I
>have
>> used my Johnson Matchbox Antenna Tuner to operate o any
>> > h.f. band, as well on 10 meters, while feeding my 80 meter antenna with
>> excellent results. - 73's- Sherrill W. k4own
>> >
>> > --
>> > FAQ on WWW: http://www.contesting.com/tentecfaq.htm
>> > Submissions: tentec@contesting.com
>> > Administrative requests: tentec-REQUEST@contesting.com
>> > Problems: owner-tentec@contesting.com
>> > Search: http://www.contesting.com/km9p/search.htm
>> >
>> >
>>
>
>--
>FAQ on WWW: http://www.contesting.com/tentecfaq.htm
>Submissions: tentec@contesting.com
>Administrative requests: tentec-REQUEST@contesting.com
>Problems: owner-tentec@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
>
--
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
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Administrative requests: tentec-REQUEST@contesting.com
Problems: owner-tentec@contesting.com
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