In article ,
Bob Miller wrote:

It's probably a 4:1 voltage balun which does exhibit
a DC short. That's actually good for cutting down on
static electricity.

Okay, Cecil, Dave, one more elementary question. My copy of the
instructions for the Murch 2000B says the following:

"Connect balanced line to connection marked Balance Line with Jumper
as indicated on back panel."

On the back panel, there's a painted line between the two balanced
line connections. Surely, they don't mean to run a jumper wire between
the two connections *while* a balanced line is attached?

No, I think the painted line is meant to indicate "the line is
connected to/between these two points." The "jumper" they refer to
probably refers to a short section of balanced line, to be connected
between the transmatch and whatever terminals you use to terminate the
ladder-line or open-wire line when it comes into your shack.

It seems to tune fine without the jumper -- I'm afraid I'd blow
something up with the jumper.

Yeah, you'd be trying to tune a near-short-circuit... often difficult
and the results are less than productive :-)

There are some transmatches in which the balun is normally out of
circuit, and has to be jumpered to the hot side of the unbalanced
output when you want to use it. That *might* be what they're
referring to?

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Bob Miller wrote:
Okay, Cecil, Dave, one more elementary question. My copy of the
instructions for the Murch 2000B says the following:

"Connect balanced line to connection marked Balance Line with Jumper
as indicated on back panel."

On the back panel, there's a painted line between the two balanced
line connections. Surely, they don't mean to run a jumper wire between
the two connections *while* a balanced line is attached?

It seems to tune fine without the jumper -- I'm afraid I'd blow
something up with the jumper.

If it's like my MFJ-949E, the balun is completely out of the
circuit until the jumper is installed. Without the jumper on
the MFJ, there would be no output at the balanced line
output terminals. Do you have a schematic?
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

On Sat, 04 Jun 2005 19:24:15 -0500, Cecil Moore
wrote:

Bob Miller wrote:
Okay, Cecil, Dave, one more elementary question. My copy of the
instructions for the Murch 2000B says the following:

"Connect balanced line to connection marked Balance Line with Jumper
as indicated on back panel."

On the back panel, there's a painted line between the two balanced
line connections. Surely, they don't mean to run a jumper wire between
the two connections *while* a balanced line is attached?

It seems to tune fine without the jumper -- I'm afraid I'd blow
something up with the jumper.

If it's like my MFJ-949E, the balun is completely out of the
circuit until the jumper is installed. Without the jumper on
the MFJ, there would be no output at the balanced line
output terminals. Do you have a schematic?

Sorry, I don't have a schematic.

On my MFJ 989c, I have two balanced line connectors. I also have a 3rd
connector for Random Wire, and a 4th odd connector. For balanced line
operation, I install a jumper between the Random Wire and 4th
connectors.

On the Murch 2000B, there are two connectors for balanced line. And a
3rd connector for Random Wire. The directions seem to be saying put a
jumper on the balanced line connectors for balanced line operation.

"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


Bob
k5qwg

Bob Miller 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?
--
73, Cecil http://www.qsl.net/w5dxp

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

"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?

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.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On Sat, 04 Jun 2005 21:49:25 -0500, Cecil Moore
wrote:

Bob Miller 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?

One Balanced Line terminal goes to a balun winding wire. The second
Balanced Line terminal goes to another balun winding wire; the second
terminal also has a wire going to the Antenna Selector Switch, which
selects the balanced antenna. The Random Wire terminal has a wire
going to the same Antenna Selector Switch, which also selects the
random wire antenna.

Those are the only wires on these three terminals.

bob
k5qwg

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.

Bob Miller wrote:
One Balanced Line terminal goes to a balun winding wire. The second
Balanced Line terminal goes to another balun winding wire; the second
terminal also has a wire going to the Antenna Selector Switch, which
selects the balanced antenna.

That's different from the MFJ which has wires from the balanced
output terminals going only to the balun.

The Random Wire terminal has a wire
going to the same Antenna Selector Switch, which also selects the
random wire antenna.

MFJ saved money on the switch by combining the balanced and
random wire functions. Sounds like your tuner has separate
switch settings for balanced and random wire. So I don't
know what that jumper statement is all about.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

The line he is refering to simply indicates which of the three terminals to
connect a balanced line to. It has nothing to do with a jumper.

"Cecil Moore" wrote in message
...
Bob Miller wrote:
One Balanced Line terminal goes to a balun winding wire. The second
Balanced Line terminal goes to another balun winding wire; the second
terminal also has a wire going to the Antenna Selector Switch, which
selects the balanced antenna.

That's different from the MFJ which has wires from the balanced
output terminals going only to the balun.

The Random Wire terminal has a wire
going to the same Antenna Selector Switch, which also selects the
random wire antenna.

MFJ saved money on the switch by combining the balanced and
random wire functions. Sounds like your tuner has separate
switch settings for balanced and random wire. So I don't
know what that jumper statement is all about.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet
News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000
Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

On Sun, 5 Jun 2005 10:50:17 -0400, "Fred W4JLE"
wrote:

The line he is refering to simply indicates which of the three terminals to
connect a balanced line to. It has nothing to do with a jumper.

Thank you, that's what I finally have figured out -- Murch made
several versions of their tuner; perhaps my copy of the instruction
manual refers to some other version, or maybe they just weren't clear
in what they were trying to say.

Thanks to all...

bob
k5qwg