Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: John on May 25, 2018, 06:03:54 am
-
Hi fellas, I've got the above on my bench with a dodgy input jack (the one he uses the most is pretty shot). The other 3 inputs are not that great either, so I was going to replace all 4 since I've got it pulled apart. It's got the PCB mounted cliff jacks on it. I *think* I can replace those with Switchcraft panel mounts by using short runs of 22 ga. wire; I seem to have enough space. My thought is, use 2-3" of wire from the jack to the PCB, feed it though the holes where the cliff jacks are mounted now, mount the jacks with the PCB laying in there, then flip it over and bring the pot shafts thru the holes, and voila.
So my question is, is there some major thing I should be aware of that makes it inadvisable? I know it'd be easier just to replace with the cliff jacks, but they look pretty cheesy to me, and the Switchcraft seem to last forever. Thoughts appreciated!
-
Sounds doable to me.
-
Cool, thanks! This is my very first Fender. :icon_biggrin:
-
You should decide how to ground the new panel mounted jacks, which is a good upgrade. I did a similar mod to my Hot Rode Deluxe. Per the Unofficial HRD website, I isolation mounted the jacks, and ran a ground wire back to the point on the board. This preserves the existing ground scheme.
-
So my question is, is there some major thing I should be aware of that makes it inadvisable?
See: Murphy's Law :icon_biggrin:
-
You should decide how to ground the new panel mounted jacks, which is a good upgrade. I did a similar mod to my Hot Rode Deluxe. Per the Unofficial HRD website, I isolation mounted the jacks, and ran a ground wire back to the point on the board. This preserves the existing ground scheme.
I'll double check, but it seemed like the barrel of the cliffs are making contact right to the chassis. Thanks for the heads up though!
-
So my question is, is there some major thing I should be aware of that makes it inadvisable?
See: Murphy's Law :icon_biggrin:
Well yeah, there is that!
-
You should decide how to ground the new panel mounted jacks, which is a good upgrade. I did a similar mod to my Hot Rode Deluxe. Per the Unofficial HRD website, I isolation mounted the jacks, and ran a ground wire back to the point on the board. This preserves the existing ground scheme.
I'll double check, but it seemed like the barrel of the cliffs are making contact right to the chassis. Thanks for the heads up though!
But aren't cliff jacks plastic bodies -- so they're automatically isolation mounted?
If your cliff jack body is chassis grounded AND its ground lug is also part of a grounding scheme on the board, then there's a ground loop to be eliminated.
-
These are a combo of plastic and metal. I'll take a pic of exactly what's in there when I get home. This picture is similar, but I'm pretty sure the front of the body on mine are metal as well.
http://www.amprepairparts.com/j512.jpg
-
https://photos.google.com/photo/AF1QipMgHdWljPWw3QoctumeKZia_LNlN3BV9JcmDd_r
That's why I don't trust my memory! They are just like the ones on ampparts website, I think I just couldn't see the metal face behind the nut on the other picture. Anyway, it doesn't have ground loop issues that I know of, so I'm just gonna worry about hooking up the Switchcraft jacks correctly. ;)
-
Can't see your google photos.
-
Here we go.
-
Cool!