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
> >
> >
>
--
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