OK Teckies....I need some assistance.

[ajish4]

HELP!

Ok you tech type folks, I am going to try this on my own.....with your help of course!

I know this may be basic stuff, but I don't get it.

Here is the situation....I have a Peavey Dyna bass that needs to have the 1/4" jack replaced. It's wired correctly, just worn out, the guitar cable just falls right out.
I just purchased a NOS Peavey Jack on Ebay.
HERE:

http://www.ebay.com/itm/300644273304?ss ... 1497.l2649

As far as I know, this old bass was wired MONO, YES?

The situation is that the Jack in the bass has FOUR wires going to it. TWO in the inside ring portion, then two separate wires to two outside connectors.
I tried to take pics, but it's so tight, they just don't come out clearly. My rotten auto-focus isn't working.

What am I missing here? DO I NEED a stereo connector?

I'm totally new at this stuff guys, I'm not even sure of my soldering abilities, I'm VERY, VERY RUSTY.

Any help with a direct link to the proper part would be greatly appreciated. The TOTAL length of the jack from tip to tip is 2 1/4" long.
The guitar has a gold tone, but I really don't care, just would like a reliable, inexpensive way to do this.

Thanks!

[scotty]

I thought you typed Trekkies! Tony lol i was all ready to set phasers to stun.

[ajish4]

I thought you typed Trekkies! Tony lol i was all ready to set phasers to stun.

[jdawe]

This is a shot in the dark, since I'm not at all familiar with these basses, but my understanding is that the Dyna-Bass has an on-board pre-amp (powered by a 9-volt battery). According to the manual, which I found on line, the 1/4" jack is also used as a switch for the pre-amp, so that when the plug is removed the circuit to the pre-amp is broken (so that the battery won't drain).

This is nothing more than a guess, but it seems likely that they used a stereo TRS jack to act as a switch for the pre-amp when you insert a standard mono cable. (Indeed, the manual expressly says that a stereo cable won't work). This is a fairly standard way to use a plug as a switch. From Wikipedia:

A standard stereo jack is used on most battery-powered guitar effects pedals to eliminate the need for a separate power switch. In this configuration, the internal battery has its negative terminal wired to the sleeve contact of the jack. When the user plugs in a two-conductor (mono) guitar or microphone lead, the resulting short-circuit between sleeve and ring connects an internal battery to the unit's circuitry, ensuring that it powers up or down automatically whenever a signal lead is inserted or removed. A drawback of this design is the risk of inadvertently discharging the battery if the lead is not removed after use, such as if the equipment is left plugged in overnight.

So I'm guessing that although the bass is wired mono, you still need a stereo connector to use as the preamp switch.

What does the existing jack look like? Does it have only one piece that makes contact with the tip when a plug is inserted, or is there a second similar-looking thing that touches the plug a bit lower down on the barrel? If so, it's a stereo jack.

[rickenbrother]

Tony lol i was all ready to set phasers to stun.

He doesn't need anyone's help with that. There's already too many phasers set to stun pointed at him already!

[scotty]

Aye and Janeys in the wings with her Tinkerbell rolling pin! Sorry back to the thread....

[jdawe]

There's already too many phasers set to stun pointed at him already!

At least he hopes they're set to stun ...

[cjj]

Hey Tony, just beam it over to my house, I'll get it all sorted out for ya!





The preamp and using the jack as a switch sounds like a good possibility. Unless, yours doesn't have a preamp...

Oh, and it should be spelled "Techies...

[rickenbrother]

Aye and Janeys in the wings with her Tinkerbell rolling pin! Sorry back to the thread....

Tony doesn't know it yet, but there's a Tinkerbell tattooed on his back!

[doctorwho]

I did a quick Google search on "jack for use with an active bass" and this discussion was in the list of hits:

*** URL to other forum removed by moderator ***

Based on what I read there, a stereo jack will work by using the two lower lugs for the active (battery) on/off shorting connection.

Tony, you might want to cross-post this in The Vibrola section.

[cjj]

Gary, I deleted the link to the other forum as it's against the rules. Sorry about that...

Here's a good diagram of how a stereo jack is used for power switching (in effects boxes, but the method is the same):


Here's the actual page where that image comes from:
http://www.geofex.com/Article_Folders/w ... rapper.htm

[ajish4]

OH MAN!

Thanks everyone!

Jonathan, YES there is a preamp. It's switchable too, I can switch it on or off and run passive.

It's a barrel jack, so I can't see inside.

Gary, could you PM me that link?

CJ, I know LOLOLOL....I spelled it that way intentionally. WHY? I have NO IDEA, I just like it better!

So I take it, this isn't a good first attempt to try? I'd really like to get it working again...

Joey & Scotty.........................I'll tall ya later!

[cjj]

PM with other forum link sent...

[ajish4]

Thanks CJ,

Pm replied.

I'll try some pics in the am.

I'd really like to get this bass back into the rotation!

[jdawe]

So I take it, this isn't a good first attempt to try? I'd really like to get it working again...

I don't think this will be too tricky a project, but you're going to need to get the right part first - I'm now pretty confident that you need a stereo barrel jack, rather than the mono jack you got on eBay.

The stereo jack will have two different connectors on the back side - one for the tip and one for the ring of a stereo plug - plus a third connector on the side for the sleeve. If you look at how it is connected now and follow the wires back, I think you will find that the wire connected to the ring lead goes to the battery, the wire connected to the tip lead is your signal wire, and the two wires connected to the sleeve lead are ground. Once you figure out which wire is which, sticking in the new jack and wiring it up the same way shouldn't be too tricky.