Bare Knuckle Pickups Forum

Forum Ringside => Pickups => Topic started by: TwilightOdyssey on April 22, 2005, 04:25:53 AM

Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 22, 2005, 04:25:53 AM
Hi all,

I just wired up my guitar according to the diagram below, generously provided by a friend.

My symptom is, I'm sure, a common one, and I'm sure I'm probably overlooking something really basic here, but I'm totally lost at the moment.

I am getting the most horrific hum from both the humbucker and single coil pups until I physically touch either the control pot, the metal jacket to the guitar cord, or the claw screws to the tremolo.

FYI: The bridge pup is a 2 conductor humbucker (BK Miracle Man), with a braded shield. The neck pup is a 2 conductor single coil (BK Irish Tour). I have all of the cables grounded to the left lug of the volume control/push-pull pot, just as the drawing indicates. I also have that lug grounded to the bottom of the trem's spring plate.

Any assistance would be greatly appreciated!!

(http://img.photobucket.com/albums/v723/TwilightOdyssey/simple_switch.jpg)

Thanx in advance! :)
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Bird on April 22, 2005, 05:05:36 AM
Just a guess, but it sounds like it may not be grounded correctly.I think there's a post on it in the pickups section.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 22, 2005, 05:25:18 AM
Thanx!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 22, 2005, 06:54:31 AM
Is the body of the pot grounded?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: PhilKing on April 22, 2005, 10:07:32 AM
Is the bridge grounded?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 22, 2005, 10:20:53 AM
Quote from: PhilKing
Is the bridge grounded?


Probably

"I also have that lug grounded to the bottom of the trem's spring plate. "
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: PhilKing on April 22, 2005, 10:40:46 AM
Sorry - it's a bit early :oops:
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 22, 2005, 10:42:24 AM
Quote from: PhilKing
Sorry - it's a bit early :oops:


Know that feeling...
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 22, 2005, 02:33:54 PM
Thanx for the input, guys!

It appears that I need to attach the ground lug to the side of the pot; I tried doing so this morning, with piece of wire, and the hum stopped dead.

I will solder the wire in place tonight, and I think that my hum issue will be solved.  :oops:

I shouldn't've panicked ...

At least with a project this size, I was able to put the body aside and worked on getting the tuners into the peghead ... got 4 out of the 6 in there!

I might actually have a WORKING GUITAR tonight!!
Woo hoo! :D
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 03:56:06 AM
Okay, by connecting the ground lug to the pot, I was able to eliminate 90% of the hum ... good deal!

However, when I touch the braid to the humbucker, or the metal sheath to the cable, the hum still totally goes away.

Soooo, I know I'm missing some additional grounding. Any further ideas?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 04:58:18 AM
This is really pissing me off now!
I've tried de-soldering everything, checking all the connexions, and re-soldering them back; I'm sure that I have the basic wiring down.

I'm still getting a mid-level hum, tho, which goes away when I touch the sleeve to the guitar lead, the volume pot, or the braid to the bridge pup.

Any ideas??!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Bird on April 23, 2005, 05:08:12 AM
Could be something to do with the amp. Make sure that's not the problem.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Tim on April 23, 2005, 09:12:23 AM
What you need to do is strip it all back down again and start slowly-make sure that the bridge p/up braid, the neck black wire, the jack and the ground wire of the guitar all share common ground. If in doubt whip open one of your other axes and see how they've done it.

It's one of those things were if I had the guitar in front of me I could sort it out quickly but it's like working blind-I'm out playing tonight, won't be back till the wee hours of Sunday morning but if you're still stuck post up a pic of the wiring cavity so I can see what you've got going where and I'll try and sort it out.

good luck!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: FELINEGUITARS on April 23, 2005, 10:12:10 AM
Do a quick check to make sure you havent got the wires to the jack socket the wrong way round- it doesn't sound likee it , but always worth a check
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 04:02:22 PM
Thanx for the tips!

I've checked and re-checked, but I am now going to de-solder, cut back, and re-attach everything nice and fresh, and see if that makes a difference.

At least I was able to finish the neck while pondering the hum issue -- got the tuners and nut in; just have to screw down the tuners and string retainer.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 04:37:34 PM
Okay, here's what I did:

After disconnecting everything, I attached the humbucker directly to the output jack using aligator clips: HUM.

When I touched the SIGNAL clip, I got signal.

When I touched the GROUND clip: HUM STOPPPED.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 23, 2005, 04:54:14 PM
Quote from: TwilightOdyssey
Okay, here's what I did:

After disconnecting everything, I attached the humbucker directly to the output jack using aligator clips: HUM.

When I touched the SIGNAL clip, I got signal.

When I touched the GROUND clip: HUM STOPPPED.


This is wierd....it has to be a ground issue. If you touch the amp chassis does the hum stop?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 05:58:09 PM
Quote from: HJM
This is wierd....

Ageed.
Quote
it has to be a ground issue.

Agreed.
Quote
If you touch the amp chassis does the hum stop?

Just checked that ... yes, it stops.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 23, 2005, 06:23:12 PM
I take it that everything is fine with other guitars?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 06:31:44 PM
Yeah ... hehe, I knew that question would come up. My other guitars are fine.

I'm taking a break from it and then I'm going to try using 2 seperate wires from the output jack ... right now I'm using a single shielded cable: the center conductor as signal, and the shield as ground.

Some of my guitars have seperate wires, and some are using one ... so, I will try it out and report back!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 23, 2005, 08:12:44 PM
Wow - don't know what it is......is the internal cavity shielded...although don't know if this would make any difference! :?:
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 08:20:07 PM
Yes, the internal cavities are shielded with conductive paint.

I'm going to try the seperate wires idea, and if that doesn't work, I'll string the bad-boy up, complete the setup, and then give it another go.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Peterku on April 23, 2005, 08:43:07 PM
Did you have the cavity's shielding grounded? Don't know whether that makes a difference, though...
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 23, 2005, 09:56:03 PM
Quote from: Peterku
Did you have the cavity's shielding grounded? Don't know whether that makes a difference, though...


You can get more hum sometimes with shielding paint....you get lots of little earth loops due to variance in earth potential accross the shielding paint...hence the idea behind star grounding all earths to one point. I knew all those science lessons weren't a waste of time....(hmmm)

Not that I think that's the problem here.

If you touch the pickup wires to the jack plug, with no socket, what happens to the hum?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 23, 2005, 10:27:15 PM
Quote from: HJM
If you touch the pickup wires to the jack plug, with no socket, what happens to the hum?

I tried doing this, but it's impossible to hold the pickup wires directly to the plug without using my hands!!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 24, 2005, 09:53:58 AM
Quote from: TwilightOdyssey
Quote from: HJM
If you touch the pickup wires to the jack plug, with no socket, what happens to the hum?

I tried doing this, but it's impossible to hold the pickup wires directly to the plug without using my hands!!


Gloves?? Or do what I do and get some insulating tape and make a spot where you can hold the braid..
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Tim on April 24, 2005, 12:09:29 PM
It's definately a grounding thing, strip back the braid so you've got a nice clear section of cloth inner core.Attach the inner core to hot and the braid to cold of the jack AND then earth the jack to the guitar and the hum'll go.Connecting a pickup direct to the jack leaves it with floating ground as it's not earthed to the guitar-hum city!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 24, 2005, 01:59:07 PM
Have you re-soldered teh trem claw connection, this must be a really good, bright solder joint, if it's dull, try agai. You'll need a meaty iron, 25w will struggle, try a 40w iron to make sure - if this is a poor joint it could be the cause of the problem. :idea:
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 24, 2005, 02:14:12 PM
Thanx for the tips, gents!

My iron is a 40 watter; I will be re-checking the connexions today and getting back to ya! :)
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: HJM on April 24, 2005, 02:28:27 PM
Quote from: TwilightOdyssey
Thanx for the tips, gents!

My iron is a 40 watter; I will be re-checking the connexions today and getting back to ya! :)
Should be fine - get the claw nice and hot!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 24, 2005, 11:56:54 PM
Well, I give up. I stripped back all the cables, as instructed, and resoldered the claw ground, as well as ran 2 seperate wires from the output jack.

I STILL have a hum going on! It complete goes away when I touch the ground wires, the cable sleeve, or my amp's chasis. I have never encountered this problem ever before!!

Is there any additional place I should/could be grounding the wires to?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 25, 2005, 12:25:58 AM
Before I hand the guitar over to a tech, can I ask one extremely stupid question?

I've been doing all this work with just the body; ie, no neck, bridge, or strings on the guitar.

Stupid question: NOT having the bridge/neck/strings on the guitar should have no baring on the ground issue, should it?
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: The amazing Phil on April 25, 2005, 04:07:51 AM
My SG always had a slight hum that goes away whenever I touch the strings or hardwear. And since I'm always touching them while playing etc, it's never bothered me in the slightest. You might want to try putting it all together, then play it just to see how it all is.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: Tim on April 25, 2005, 06:25:21 AM
Jackpot! You need to have the guitar strung up and bridge on etc so that when you hold the guitar you complete the ground.
Fit the bridge,string her up, flip the guitar over and complete the soldering job,check your joints,tune up and you'll be rocking.
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: The amazing Phil on April 25, 2005, 01:06:58 PM
If only we thought of this before it got soldered 20 times eh? :lol:
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 25, 2005, 01:08:58 PM
LOL!

I can't believe it .... :shock:

Ah well, live and learn, as they say!  :oops:

I shall be stringing up the neck tonight, tuning, etc ... almost there!!

THANX FOR THE HELP!
Title: ** WIRING ASSISTANCE NEEDED** (Pic incl.)
Post by: TwilightOdyssey on April 25, 2005, 01:10:39 PM
Quote from: The amazing Phil
If only we thought of this before it got soldered 20 times eh? :lol:

LOL! Totally!
I think it's a natural assumption that the guitar is together during all of this, not in "kit form"; but, this particular guitar is a complete rebuild on my part.