Switch Craft jacks

[billyz]

It is even harder to fix a cliff jack than a good ol Switchcraft. I use a small needle nose plier . First pull the tip contact back a little then use the plier to twist (and or push/pull) the shorting contact to the tip contact. It does not have to make yet. Let the tip back and see if you have it closed. Also, I use a little sandpaper to clean up old jacks , just slip it thru a few time with some d5. I think I can make a switchcraft last for decades.

there are a bunch of chinese look a likes too, not as good ( junk)as the american made switchcraft. If They are making them in China then it is the end.

[M Fowler]

I prefer the switchcraft long thread jacks but since I am doing some Marshall and Hiwatt builds I wanted to with Cliff jacks.

I have never had a problem with high quality phono jacks and surely keep away from the cheap ones.

[David Root]

Tom the FET jack is Switchcraft 14B.

[Structo]

Thanks David but what is the one in #124?

Also, I would need a diagram to figure out how to wire it.

[M Fowler]

iknowjohnny,

The chrome nut cliff jacks I just received indeed are the long ones that work with faceplates, nice.

http://www.mojotone.com/amp-parts/Jacks ... Chrome-Nut

[Gaz]

So those have 3/8" long bushings like the Switchcraft long-bushing jacks? ...I've been having trouble with the shorting switch on them as well. bummer.

[M Fowler]

For no face plate, use the supplied two washers. For use with faceplate remove one washer and they fit perfect.

Mark

[David Root]

Tom, the standard #124 layout that Tony recently updated shows how to wire it. That's how I wired mine, by following the layout.

[David Root]

Just got another bad Switchcraft, managed to destroy it too.

The second one in the same position in two different amps, the internal loop Return jack. If it doesn't make firm contact, the signal partly bleeds off to ground thru the 220K grid leak attached to the tip contact. Sounds like s**t!

Does any other company make solid Switchcraft jacks like Switchcraft used to make?

[greenbottle]

Way back when i first found this wonderfull site I downloaded a cct diagram IZ4 rev2.4 4/2/08. I have just done a search for IZ4 with a zero result.

If you look at Rob Livesey site www.roblivesey.com/dumble the 124 gut shots :- row 7 , col 1 you will see the FET jack. A great big square thing with multiple tags out the back. IZ4 lists this as
Kobiconn 161-0083-E and I think you can get them from Mouser and Small Bear.

Most of the current cct diagrams show a stereo switched open jack.

If you go to www.switchcraft.com/products/jack-85.html I think 14B is the one required. Towards the bottom of the page there is a link to dimensional drawings and to insulated monting information.

Also the jack-101a.html may be of some interest.

Alan

[flythair0]

Mouser sells the mil-spec version of the standard Switchcraft jack but not with a long barrel for the thicker panel. They are quite a bit heavier built with better switch contacts but higher priced as well. The Mouser number is 502-C12AX. $6.20 ea for singles, 5.12 for 10 or more.

Scott

[David Root]

Thanx for the tip! The MILSPEC are better.

Right at the bottom of the spec sheet:-

"* Commercial jacks feature integral contacts. Integral contacts should not be used where low contact resistance is a requirement."

The MILSPEC jack is lower contact resistance:-

"Contact Resistance:

Commercial Jacks - .030 ohms maximum (initial), .050 ohms maximum (after humidity, durability exposure). Per MIL-STD-202E.

Military Jacks - .010 ohms maximum (initial), .020 ohms maximum (after life), .10 ohms maximum (after salt spray). "

And here's why the MILSPEC is better:-

"Integral contacts are standard in the isolated switching circuits; fine silver contacts in C12A switching circuit."

So I discovered the hard way that in any circuit where the pin and shunt contact is connected to ground directly thru a resistor, as in my case in the Send jack in my loop, the standard commercial grade jack may not cut it.

I'm going to get 10 of the C12AX Mil-Spec jacks and compare them.

[Cliff Schecht]

I didn't know about those either. What's the price difference like?

[David Root]

Double. $5 each if you order 10, $6 each below that.

Silver has doubled this year to $30/oz.