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Old June 5th 05, 04:25 AM
Bob Miller
 
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On Sun, 05 Jun 2005 03:21:08 -0000, (Dave Platt)
wrote:

"Connect any antenna with single wire feed to connection marked Random
Wire. Connect balanced line to connection marked Balanced Line with
Jumper as indicated on back panel." (and there's a painted line
between the Balanced Line connectors.)

If it's helpful, there are pictures, inside & out, of the Murch tuner at
http://cgi.ebay.com/ws/eBayISAPI.dll...m=5757714 402

I suspect the jumper wire needs to go between the random wire
terminal and one of the balanced line terminals. That's the
way it is on my MFJ. On the inside, do the balanced line
terminals go anywhere besides the balun?


According to one note I saw on the net, many of the Ultimate
Transmatch designs had an internal strap/jumper to connect the
unbalanced tuner circuitry to the balun, when necessary.

I rather strongly suspect that this is the case for the Murch. The
photos show that it has internal switching of the tuner output. The
switch has five positions - 1 2 3 (which I assume correspond
to the three unbalanced jacks) and two I can't really read clearly in
the photo - perhaps the random-wire output, and the balun for the
balanced output?


That's right, the 5-position Antenna switch selects coax 1, 2 and 3,
and R for Random Wire, and BL for balanced line.

bob
k5qwg



Sounds to me as if no external hot-to-balun jumper is requires,
especially as the OP reports that it tunes a balanced antenna just fine
without one.