Andy R Posted August 10, 2011 Share Posted August 10, 2011 The jack is wired to the tone pot, with the (ground, neutral, whatever) to the back of it. ALL the pots are wired together on the back (yellow) and the neutral from the pups as well. that means if the switch is wired to from the center (as it APPEARS?) in the photo to the back of the pots (yellow) that would mean the hot and neutral of the pups would be a short. I (we?) are missing something or not seeing the way the switch is wired. It should NOT work. I love a good mystery. Not when the pickup selector isn't in the middle position.... Link to comment Share on other sites More sharing options...
stein Posted August 10, 2011 Share Posted August 10, 2011 Not when the pickup selector isn't in the middle position.... I thought the center lug of the switch was the hot that would complete the circuit for the pups. I.E. left brown to yellow, both brown to yellow, right brown to yellow. Link to comment Share on other sites More sharing options...
Andy R Posted August 10, 2011 Share Posted August 10, 2011 I thought the center lug of the switch was the hot that would complete the circuit for the pups. I.E. left brown to yellow, both brown to yellow, right brown to yellow. You're exactly right so think about it... When the switch is one way or the other one of the pickups isn't being sent to ground... Link to comment Share on other sites More sharing options...
stein Posted August 10, 2011 Share Posted August 10, 2011 You're exactly right so think about it... When the switch is one way or the other one of the pickups isn't being sent to ground... AHA!!! I will look again. Link to comment Share on other sites More sharing options...
stein Posted August 10, 2011 Share Posted August 10, 2011 OK...still, the brown wire to the switch has got to complete the circuit SOMEWHERE...so if it isn't the yellow, then it must be the red. And, still, there must be something about the switch I don't see. If the switch is somehow using the red as the hot, then that would explain the use of 3 wires for a "kill" switch. Link to comment Share on other sites More sharing options...
Andy R Posted August 10, 2011 Share Posted August 10, 2011 OK...still, the brown wire to the switch has got to complete the circuit SOMEWHERE...so if it isn't the yellow, then it must be the red. And, still, there must be something about the switch I don't see. If the switch is somehow using the red as the hot, then that would explain the use of 3 wires for a "kill" switch. A couple of notes: When I said here is the ground I meant what should be the ground for the 3 way selector switch. Also called the "output" the "Input" but you should get the gist... http://www.youtube.com/watch?v=TY0HZQ81uLw Link to comment Share on other sites More sharing options...
Andy R Posted August 10, 2011 Share Posted August 10, 2011 And here is a vid with the red and yellow wire swapped ( I also twisted the red and white wire just to provide a bit more shielding. I am also not consistent with my usage of the kill switch being on or off but again you will get the gist. BFG in short.... Just swap the yellow and red wires on the 3 way pickup selector and 99% of you issue will be gone... Andy http://www.youtube.com/watch?v=gWfeP_jZx90 Link to comment Share on other sites More sharing options...
stein Posted August 10, 2011 Share Posted August 10, 2011 ANDY: Brilliant! And, it sounds fine as far as noise. So..just for my own learning, Am I to understand that what WAS happening is that the signal was "bleeding" through the ground? (it sounds like it from what I can tell with the reduced output and picking up all that noise). Also, not that I would change it, (well, I might)...why THREE wires for the kill switch? would it not be quiter if it was just used as a short? (in other words, just one additional hot parallel from the switch or jack to the center of the kill switch, and a ground to short the signal on one of the outside lugs. I am assuming it is a SPDT switch). Link to comment Share on other sites More sharing options...
Lammas Day Posted August 10, 2011 Author Share Posted August 10, 2011 BFG (TAR)? How is it going? I hope all this technical stuff isn't overwhelming you or scaring you off. We here to help if you need it. I have to leave for work soon, but me and the guys on this thread have a history of sticking around to help "fix" stuff when it needs fixing. Hahahaaa - yeah, I'd like you to imagine my jaw slowly dropping and some drool coming out the corner. I'm just seeing how much it'd cost to fly the guitar to Indiana... Annnddddyyyy :) The trouble is though, I've only used a soldering iron twice (not in anger) once to fix an input jack on my Peavy Classic Chorus combo, and the other to fix a thermostatic control switch on a shower - both worked, but starting to pull out the wires on my guitar needs some deep breathing and just focus the mind :) I've not got the copper tape yet, I'm going to try Andy's fix before that and I'll let you know - probably be the weekend because I'm looking the kids, and kids and solder don't mix. Keep you updated Link to comment Share on other sites More sharing options...
stein Posted August 10, 2011 Share Posted August 10, 2011 Hahahaaa - yeah, I'd like you to imagine my jaw slowly dropping and some drool coming out the corner. I'm just seeing how much it'd cost to fly the guitar to Indiana... Annnddddyyyy :) The trouble is though, I've only used a soldering iron twice (not in anger) once to fix an input jack on my Peavy Classic Chorus combo, and the other to fix a thermostatic control switch on a shower - both worked, but starting to pull out the wires on my guitar needs some deep breathing and just focus the mind :) I've not got the copper tape yet, I'm going to try Andy's fix before that and I'll let you know - probably be the weekend because I'm looking the kids, and kids and solder don't mix. Keep you updated The fix WILL work. ANDY has done it and tested it in real life, and even with vids. Seriously, good work there by Andy. Besides catching the problem, it really IS kinda goofy wiring on Gibson's part, and I think he saved you a LOT of hassle, as I doubt there is a common diagram and I doubt Gibson even has one. It should be easy, but feel free to get back should a problem arise or you have any questions how to go about it. Link to comment Share on other sites More sharing options...
Lammas Day Posted August 10, 2011 Author Share Posted August 10, 2011 The fix WILL work. ANDY has done it and tested it in real life, and even with vids. Seriously, good work there by Andy. Besides catching the problem, it really IS kinda goofy wiring on Gibson's part, and I think he saved you a LOT of hassle, as I doubt there is a common diagram and I doubt Gibson even has one. It should be easy, but feel free to get back should a problem arise or you have any questions how to go about it. just to double check what fix we're talking about, we talking about the first fix where I'm twisting the red and white wires from the kill switch to shield themselves etc - or should I re-read everything again? (APPOLOGIES, i don't mean to be disrespectful, I appriciate the wisdom VERY much, but as this is pretty new territory I can;t take in everything I've read on this post, so i had to skim read some of it ) Link to comment Share on other sites More sharing options...
Andy R Posted August 10, 2011 Share Posted August 10, 2011 just to double check what fix we're talking about, we talking about the first fix where I'm twisting the red and white wires from the kill switch to shield themselves etc - or should I re-read everything again? (APPOLOGIES, i don't mean to be disrespectful, I appriciate the wisdom VERY much, but as this is pretty new territory I can;t take in everything I've read on this post, so i had to skim read some of it ) BFG, No problem man... I'm not sure how much the twisting of the wires reduces the hum but doesn't hurt. You could just de-solder the Red wire and the Yellow wire on the 3 Way pickup selector and swap them. That is what is going to fix 90% of the hum and buzz. Should be a 5 minute fix. The "buzz" is 90 percent of what you are hearing and that is due to having a hot lead connected to the ground lug on your switch which is pretty much the same as what happens when you have a guitar cable plugged into an amp without it being connected to the guitar. The "Hum" you can determine if it is acceptable after you correct the first issue. I think it will be fine as in my example the amp was about 2 ft away and everything was exposed.... If the hum is still too much we can make suggestions for fixing it. Possibly wiring the switch differently, shielded cable and shielding the cavities with copper tape etc... Good luck! Andy Link to comment Share on other sites More sharing options...
Andy R Posted August 10, 2011 Share Posted August 10, 2011 ANDY: Brilliant! And, it sounds fine as far as noise. So..just for my own learning, Am I to understand that what WAS happening is that the signal was "bleeding" through the ground? (it sounds like it from what I can tell with the reduced output and picking up all that noise). Also, not that I would change it, (well, I might)...why THREE wires for the kill switch? would it not be quiter if it was just used as a short? (in other words, just one additional hot parallel from the switch or jack to the center of the kill switch, and a ground to short the signal on one of the outside lugs. I am assuming it is a SPDT switch). Yep .... I think it was bleeding through because of the output being connected to the tone control and the tone control doesn't have a leg that is directly grounded so there is no dead short to the output. It was just passing the signal through the ground circuit. The red wire was just an "open" output that was buzzing through the grounding chassis of the 3 way selector switch. I probably could have removed it and the circuit would have still "worked" with a bit less buzz. Concerning this switch and wiring you need three wires. A signal input to the killswitch which would be the center (output) of the the 3 way selector switch. Then you would need a way to return the signal ( the white wire from the switch) and a way to short the switch which is the leg to ground... So you are essentially splitting (tapping) the output lead of the middle lug on the three way switch and then cutting the connection by sending it to ground.... You might be able to use 2 wires and a switch to break the ground instead of breaking the hot signal.... Have to think about that one. Might cause switch popping... Andy Link to comment Share on other sites More sharing options...
Lammas Day Posted August 10, 2011 Author Share Posted August 10, 2011 BFG, No problem man... I'm not sure how much the twisting of the wires reduces the hum but doesn't hurt. You could just de-solder the Red wire and the Yellow wire on the 3 Way pickup selector and swap them. That is what is going to fix 90% of the hum and buzz. Should be a 5 minute fix. The "buzz" is 90 percent of what you are hearing and that is due to having a hot lead connected to the ground lug on your switch which is pretty much the same as what happens when you have a guitar cable plugged into an amp without it being connected to the guitar. The "Hum" you can determine if it is acceptable after you correct the first issue. I think it will be fine as in my example the amp was about 2 ft away and everything was exposed.... If the hum is still too much we can make suggestions for fixing it. Possibly wiring the switch differently, shielded cable and shielding the cavities with copper tape etc... Good luck! Andy Fantastic Andy, that's turned from something I was crapping my pants about starting, to a simple switch over which I'm really looking forward to having a go at - will of cause keep you posted. Before that though, can you add some background understanding to help me build up confidence to tackle something more advanced? My question is related to soldering the pots. I had a real close look at them, for the first time properly LOOKED, and it didn't seem to follow what I would of thought would of been normal mechanical/engineering/common sense. What I was expecting was a pot with tabs on, to where the wires were soldered, but as my photo shows, in many places wires are soldered just seemingly randomly blobbed onto the tops - I don't know the internal workings of a pot but wouldn't terminals to be wired be neatly arranged around the edge? (I mean, OBVIOUSLY not as it works as it is, but like I said, just to give me an idea of what's happening when a signal goes through) Link to comment Share on other sites More sharing options...
Andy R Posted August 11, 2011 Share Posted August 11, 2011 [<br> Link to comment Share on other sites More sharing options...
Andy R Posted August 11, 2011 Share Posted August 11, 2011 Man you are a glutton for punishment.... You apparently don't know how long winded I can get on these topics but I will try to keep it brief... So lets start by looking at the "innards" of a typical Potentiometer ( AKA "Variable Resistor") Notice that the lugs on each side are connected to the "resistive element" and the middle lug is connected to the "Rotating Dial" commonly referred to as the "Wiper" . When you turn the knob you are moving the wiper across the resistive element. As the wiper travels along the resistive element the resistance changes between the outer lugs to the center (wiper lug) So for example if you had an ohm meter and measured between the center lug and the lug on the right the more you moved the wiper to the left the more the resistance would increase. At the same time if you were measuring between the center lug and the left lug the resistance would decrease. In the picture below there would be more resistance between the middle lug and the right lug than there would be between the middle lug and the left lug. There are 2 main "types of Pots" one is linear and one is Logarithmic. A Linear Pot would have an equal amount of resistance between the outside lugs and the center lug when the pot is turned so the wiper is centered on the resistive element. So if it were a 5ooK pot when the pot is in the middle you would have 250K per side measured to the center lug. A logarithmic Pot would be weighted with more resistance towards one side or the other. So that is what is happening inside the pot as you turn it one direction or the other. End of part 1... Link to comment Share on other sites More sharing options...
stein Posted August 11, 2011 Share Posted August 11, 2011 NOTE: resistance is exactly what it sounds like, it RESIST electrical current. it is measured in OHMs , which is a random word (named after the OHM guy, you came up with the concept). The "k" after the number means x1000, so, 250k is a short way of saying "250,000 OHMs of resistance" to an electrical current. Another way to view it: look at the pic ANDY has of the pot. Imagine that is my head. the sweeper is my memory. the lugs on each side are my ears. the further away from my ear the sweeper is, the more resistance to the info I have coming from my ear to my brain. Link to comment Share on other sites More sharing options...
Andy R Posted August 11, 2011 Share Posted August 11, 2011 Then ponder on these for a while... Link to comment Share on other sites More sharing options...
Andy R Posted August 11, 2011 Share Posted August 11, 2011 Here are some good Links to watch. http://www.youtube.com/watch?v=rUkrpqEmXb8 http://www.youtube.com/watch?v=kTooyaxdDV0&feature=related Link to comment Share on other sites More sharing options...
Andy R Posted August 11, 2011 Share Posted August 11, 2011 More good info: watch the wiring Series this guy has. It is very good. http://www.youtube.com/watch?v=EHA4SLN4qeA&NR=1 Also check out the DIY Link in the Epiphone forums... Lots of good stuff here. http://forum.gibson....ated-questions/ Link to comment Share on other sites More sharing options...
stein Posted August 11, 2011 Share Posted August 11, 2011 Good links on how to do the work of wiring. The truth is, 90% of the time when we wire we just follow a diagram, not really needing to know exactly how it works. Sometimes, we know how SOME of it works, and sometimes, understand it fully. Or, put another way, you can competently wire up a guitar following a diagram without needing to know how it works. You can modify part of it knowing how some of it works (or come up with your own design by modifying and known diagram) OR, start from scratch and design the whole thing. Not trying to take anything from ANDY (he not only knows a lot, but he is pretty smart as well)... To answer about the pots, there are 2 things to understand. 1) they work by grounding, and are backwards in the sense that full on decreases less than half on), and 2) guitars are SINGLE ENDED in design. Link to comment Share on other sites More sharing options...
stein Posted August 11, 2011 Share Posted August 11, 2011 PART ONE: a potentiometer role in a guitar. EDIT: A short is when the positive and negative wires touch before they go through the circuit, (no sound) as opposed to a break in the wire (open circuit). A pot works as a volume by GROUNDING the hot signal. At full off, the signal between the hot and the ground are completely connected, which makes a "short", and there is no sound. When it is turned full up, there is RESISTANCE to ground. The more resistance you have to shorted signal, the more signal gets through. So, that is why a 500k pot is louder than a 250k pot. The 500k has more resistance to a signal, and it would make sense to think the more resistance you have, the less signal you get. But, we wire them NOT to give resistance to the hot signal, it RESIST the hot signal to being a dead short. Link to comment Share on other sites More sharing options...
Lammas Day Posted August 11, 2011 Author Share Posted August 11, 2011 The truth is, 90% of the time when we wire we just follow a diagram, not really needing to know exactly how it works. Sometimes, we know how SOME of it works, and sometimes, understand it fully. Yeah, I hear ya brother. I've spent many years teaching IT to people without any idea under the same premise, I'm the biggest advocate of "blaggers guide". As I've said before, if Michael Schumacher couldn't change a spark plug, it wouldn't stop him from being a phenomenal driver - you don't need to now how it works, just that it does work (if you do THIS, THIS and THIS... in that order... don't touch that though) Andy - all modesty aside, I could read stuff like that all evening. I've already downloaded your flv files and PDF'd the text for future. I'm a shameless student, I LOVE hearing from people who know their onions, I don't care if I sound stupid, just really happy to be learning more. Thanks again fellas, hope I can repay the help sometime. Link to comment Share on other sites More sharing options...
stein Posted August 11, 2011 Share Posted August 11, 2011 PART TWO: single ended design. (SUBTITLED: what the heck are you talking about Stein?) As everyone probably knows, in order for electricity to flow, there needs to be a positive and a negative. "single ended" is jargon used to describe an audio design as opposed to "balanced". When ever a electrical charge goes through something, there is a positive charge and a negative charge. In a "balanced" design, there is 2 signal carrying wires (positive and negative) and, a ground (to soak up stray signal that may have noise or buzz, stuff we don't want). Easy to understand, right? Both signals are equal, and both are connected the same to complete our circuit. In a "single ended" circuit, only ONE wire is used to "read" the signal, although the is still a negative wire in the circuit. Although there is two signals present (+ and -) only ONE of the wires is used to transfer the audio signal. The "other" wires besides this single wire are only to serve to allow electricity to flow in both directions, but the audio signal is not read from it. In this way, there does not have to be 2 equal wires, or 2 signal carrying wires, just so long as the signal carrying wire has a place to have the other half of the charge go. In the case or a guitar, the ground wire is used BOTH for collecting stray signals, and a place for the other half of the signal wire. Link to comment Share on other sites More sharing options...
stein Posted August 11, 2011 Share Posted August 11, 2011 SUMMING UP 1 AND 2 (the back of the pot) Using the ground as both the other half of the signal and a place to dump stray signal is only effective if the negative has more potential than the positive. Picture a shielded guitar cable. it is relatively quiet because the ground wire surrounds the hot, and any likely stray signals are likely to be picked up by the wire surrounding the hot. But, ALSO, there is MORE of the negative wire than there is the positive, (more potential to hold a signal). Any stray signal is likely to move from the smaller positive wire to the shield than it is for the signal to stray from the shield to the positive wire. So, in this way, using the metal casing on the back of the pot is a good way to use it for both a negative and a shield. Link to comment Share on other sites More sharing options...
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