Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dude on March 22, 2012, 04:25:23 pm

Title: NOS Switchcraft jacks (How too wire)
Post by: dude on March 22, 2012, 04:25:23 pm

I got several packs of these old Switchcraft jacks at a Guitar show

I can see the tips gets soldered in the well, solders nicely but how do you attached the ground?

There's no place to solder...? I soldered the ground to the sleeve but a lot of medal to heat..?

Anyone seen these jacks before and how to attach the ground side?

Thanks as always,

al

Title: Re: NOS Switchcraft jacks (How too wire)
Post by: Willabe on March 22, 2012, 04:36:00 pm

They look nice and strong.

Some guys might have just used the crimp band, but I would think that the connection over time will fail because of corrosion.

If you pre-tined the ground wire and used a hot/big enough iron it well bond/solder well to the sleeve. I'd sand the sleeve where it would be soldered to with fine sand paper right before being soldered.

Title: Re: NOS Switchcraft jacks (How too wire)
Post by: stratele52 on March 22, 2012, 04:37:21 pm

You solder the ground on the long sleeve/ body. Yes it is a lot of metal too heat .

Title: Re: NOS Switchcraft jacks (How too wire)
Post by: stingray_65 on March 24, 2012, 12:44:59 am

Those are some REAL nice jacks you got there.

Those jacks were made specifically for telephone switchboard operators and designed to make over 1,000,000 connections before failure. They are HEAVY DUTY industrial grade parts.

When soldered properly, high heat and flux, using the proper cable, they will give years of good service.

the cable that was intended for had a cloth covered center wire and cloth covered jacket, it did not melt like some modern plastic insulation will.

Solder the braid to the sleeve as you called it first, leaving the center conductor a bit long.

Then  trim the  center conductor and strip, solder it into the well.

A Weller soldering gun is useful here.

Ray

Title: Re: NOS Switchcraft jacks (How too wire)
Post by: dude on March 24, 2012, 12:46:08 pm

Ray, thanks. I did use standard instrument cable available today.

I cut the cable to the proper spec's and before I did the tip I soldered the ground to the sleeve with the cable wire hanging.
Surprisingly, the metal heated up faster then I expected.  I wonder what the "gold colored metal is..?" Finished with  the tip, used the clip to hold the cable.

I did notice that the jack is a little thicker than a normal guitar jack, but still fits. It's nice and tight.
I picked up 10 packages for a dollar each at the Phila. Guitar show a while back, I bought all he had. He had NOS sockets for dollar, too. All kinds of nice goodies. He wasn't there last year. I remember the guy telling me he can't make a buck anyone doing this, too bad I miss his table every time I go the show, maybe he'll be back later this year...?

What's the best cable to use without biting my wallet? I'm tired of stepping on the cable and destroying the plug. Even the newer Switchcraft jacks bend when to step on the cable doing a Neil Young...,ha.

Thanks,

al

Title: Re: NOS Switchcraft jacks (How too wire)
Post by: stingray_65 on March 24, 2012, 11:31:15 pm

Quote from: dude on March 24, 2012, 12:46:08 pm

I wonder what the "gold colored metal is..?"

a beryllium copper alloy or phosphor bronze alloy, which is also a copper alloy.

no opinion on "best" cable.

a lot like asking what's the best coupling cap.

Ray