I think by what was meant is that the Matchbox has a lower impedance
matching range when compared to the "infamous 'T' match" circuit. I know
the 'T' matches I have owned or built were capable of handling several
thousand Ohms. I believe the Johnson Matchbox upper limit is something like
1200 Ohms.
By the way I used my Matchbox on the WARC bands. You just use which ever
position of the band switch works for that particular WARC band. The 40
meter position usually handles 30M, either the 20 or 15 meter position for
17M, and the 10 meter position for 12 meters.
I have also had success using the Matchbox as well as 'T' matches and the TT
238 on 6 meters using either a 160 foot dipole (with balanced feeders), or a
200 foot longwire.
Reid, K7YX
-----Original Message-----
From: Sherrill WATKINS [mailto:SEWATKINS@dgs.state.va.us]
Sent: Wednesday, March 29, 2000 1:18 PM
To: tentec@contesting.com; SEWATKINS@dgs.state.va.us;
reid.w.simmons@intel.com; jmlowman@ix.netcom.com
Subject: RE: [TenTec] Re: Ten Tec antenna tuners
I don't mean to keep beating a dead horse, but I really get a good laugh
when some of you microprocessor types tell me what narrow bandwidth my old
Johnson Matchbox has! I have used it to feed 500 watts into my 130ft.
center fed zep from the low end of 80 meters to the high end of 10 meters
with perfect match beween the tuner and my transmitter. Oh yes, for you
mathematics types that is called a conjugate match. I'll agree, I haven't
tried to use it to load my 2 meter rig into my 130 antenna as of yet. I
will conceed that it lacks the bandswitch positons for the WARC bands. Heck,
it was made 20 years before those bands were even though of! By the way,
on 10 meters I estimated the vswr at 8 to 1 and the old Johnson Matchbox and
the open wire line just keep on working great with excellent signal reports
and with no heating what -so- ever. ( Also, i conceed that I have not tried
to tune a mobile antenna with it.) By the way, it was rated at 250 watts of
100 percent plate modulated A.M. That translates to 750 watts of pep ssb!
Narrow bandwidth?? BALONY! - Sherrill W. k4own.
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