1/4" jack needed, tip is shunt, isolated make circuit

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xtian
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1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

This Mesa Mark I schemo shows a special jack with the standard tip shunted to ground when no plug is inserted, and ALSO an isolated make circuit. I'm not able to find both of these options in the Switchcraft line. Anyone know how to find?

I actually need this specific jack for my Mitchell Pro-100!
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Smokebreak
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by Smokebreak »

I think it's the 113 and I only say that because I found this thread a while back while researching the MkI. Looks like switchcraft carries 113X
http://music-electronics-forum.com/t269/
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

Good try, but nope. Not the 113, nor any other listed on this PDF:

http://www.switchcraft.com/Drawings/110 ... ies_cd.pdf
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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

Here it is, in this PDF:

http://www.switchcraft.com/Documents/Ja ... matics.pdf

See XI (J4-1A).

OK, where do I order...
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by rock_mumbles »

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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

rock_mumbles wrote:I thought this was it but it's not exactly it ...

http://www.tubesandmore.com/products/W-SC-13

http://ax84.com/bbs/dm.php?thread=459968
Right, that's what's in the amp now, and the problem is it does not short the grid to ground when no plug is in the jack, and then you get some unwanted hum from the unused gain stage.
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Structo
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by Structo »

Tom

Don't let that smoke out!
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randalp3000
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by randalp3000 »

these old schematics don't show shorting jacks for the Mk1's or SOB?
http://www.webphix.com/schematic%20heav ... oogie.html
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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

randalp3000 wrote:these old schematics don't show shorting jacks for the Mk1's or SOB?
http://www.webphix.com/schematic%20heav ... oogie.html
I agree, they don't. But they don't show EITHER jack shorting the tip to ground, and I know that causes trouble in a high-gain amp!
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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

Structo wrote:How about the 14B?

http://www.switchcraft.com/Drawings/14b_cd.pdf
Has a "break", not a "make" circuit, and not isolated. Thanks, though.
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randalp3000
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by randalp3000 »

You could shoot Boogie an e-mail. They're usually pretty nice and helpful. Could be something proprietary that's custom made.
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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

randalp3000 wrote:You could shoot Boogie an e-mail. They're usually pretty nice and helpful. Could be something proprietary that's custom made.
Yes! Did that this morning. Will let you know.
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by JazzGuitarGimp »

xtian wrote:
randalp3000 wrote:You could shoot Boogie an e-mail. They're usually pretty nice and helpful. Could be something proprietary that's custom made.
Yes! Did that this morning. Will let you know.
I had a pleasant exchange with MB when I had a DC5 on the bench for repair. I'm sure they will help you out.
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xtian
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Re: 1/4" jack needed, tip is shunt, isolated make circuit

Post by xtian »

Yup. Just got off the phone. Part 610130. $12.95 (!!) plus shipping.
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