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Chat about Equipment Info
 #74836  by erock
 Wed Feb 24, 2010 1:07 pm
I haven't tried melting them with a lighter :) I figured it was wasn't pure graphite.

since i'm lazy, and don't have shielding material on hand so I'll see what happens when i go (not so crazy) at it with my wire clippers.

I have wondered how I could ground the switches. I may have to bite the bullet on shielding it, but I'll hold off and see if this corrects the problem.

perhaps I'll just order some shielding tape as well
 #74973  by erock
 Fri Feb 26, 2010 9:08 am
ok i cleaned up the shielding, and re-did some of the grounding.
I made a schematic of the wiring, but think i need to go at with some colored pencils, as all i had on hand was a sharpie. its a mess. I also think some of my solders onto the bare ground wire may be cold, and could cause some problems down the road, so I am going to re-do them this weekend with my soldering gun as that will be a lot quicker than with my 30 W iron. Another potential i thought of for a ground loop would be the brass plate connecting the two outputs. could this cause a loop?

i really should just shield this sucker.

for posterity, here's the drawing i did last night. it's a mess. Does anyone know a good free/cheap software I could use to draw it out?

Image

<edit>
for the record, crackle is still there, and I noticed it is really only there when i run the pickups in series. parallel is fine as is north coil. I do have the pickup shields connected together, then running to ground. I am going to change that to connect the shield to the ground point on each pickup switch just to keep them apart until it hits ground.
 #75152  by JonnyBoy
 Wed Mar 03, 2010 11:24 am
Since the post about where to get a reup on these picks surfaced, in a few days their quantity went from 120 bags to 10. Wow. I wonder how many here made a mad dash. :lol: At least their hopefully staying with those (family) that appreciate them, hopefully not on Ebay where they're trying to sell them for $100 a bag. That's just plain wrong, yet the American way. The guy even has them displayed on a "Head" styled guitar. To give him some credit and doubt, he may not know they still sell them. Also, he is giving some proceeds to charity :smile: . What ever they are worth to you is the point. Peace.
 #75202  by erock
 Thu Mar 04, 2010 7:13 am
update, in addition to the ground loops from the shielding, there was a ground loop through the brass plate around the jacks. I snipped the ground going to the sleeve of the effects loop, and no more crackle (ground is still getting to the sleeve via the plate). Everything is playing nicely, no more crackle or buzz.

now all that is left is i need to re adjust the pickups higher, and it should be good to go.
 #75208  by tcsned
 Thu Mar 04, 2010 8:12 am
hmmm . . . I might be having a similar issue, I'll check it out - though no effects loop or preamp on mine. Strange that I only have the issue using my Twin not the Boogie or the JCM 800. Good news, I found an unopened bag of Adamas picks while looking for a guitar synth cable in my huge pile of old musical crap. I saw someone selling those picks for like $10 each on eBay - pretty insane. Didn't find a synth cable though dammit.
 #75209  by erock
 Thu Mar 04, 2010 8:17 am
maybe there is a grounding issue on your twin then?

on my guitar, i had the issue on every amp i tried (probably three of them), and with every cable i tried.

I have several bags of Adams picks un-opened. when i found out months ago Dunlop still had them, I stocked up.
 #109744  by erock
 Sun Feb 19, 2012 9:35 pm
Bump

After this problem being intermittent for a while, I finally solved it.

Instead of just testing for continuity, I decided to check the ohms at various ground points.
Everywhere inside the guitar I was getting about .4 ohm of resistance. From anywhere in there, to the strings, I was getting 10 ohms. Not enough to break continuity, but enough that I was becoming the quickest path to ground when touching the strings.

I putzed around with the wire going to the bridge, and problem was solved.