Invader Jim

Read my first posts before asking a question! We are here to HELP you, not do it FOR you. All the info you need is on this page. Unlike 99% of 'Ultimate Thread' starters, I've been active in this thread since the beginning. As such, I have continually updated it with info from certain posts within this thread. This makes the size of the thread irrelevant, for those of you looking for an excuse not to read this page. If it isnt on the first page, it most likely isnt in this thread.

There are links on this page that TEACH you about this stuff (highlighted in red text below). If you learn about the components and how they interact, you can do this stuff for yourself, and maybe even help out others! Please read up on this stuff.


Couldn't have said it better myself.

For links to many other great threads, check out the GB&C Central Hub.

I'm gonna keep this mostly about guitar and bass wiring issues. Do not ask for pedal or amp schematics. We're not in that business. If you looked through these first posts and didn't find what you needed and you still have a question, feel free to post it!

It's my belief that if someone is looking for wiring diagrams, the first place they'd look is the website of some big-name manufacturer. Apparently, though, this isn't the case...

So here are some helpful websites with plenty of wiring diagrams. I even linked directly to the page so you don't have to search the site.

Seymour Duncan
EMG
Fender
DiMarzio

And here are some other sites that are just chock-full of useful info:
http://music-electronics-forum.com/...read.php?t=2114- This may help out if you have any noise issues you can't resolve.

http://www.audereaudio.com/FAQ_PUNoise.htm- This may help out if you have any noise issues you can't resolve.

http://www.audereaudio.com/FAQ_PUMag_Gnd.htm- This may help out if you have any noise issues you can't resolve.

http://guitarnuts2.proboards45.com/...lay&thread=3159- Mods to the Jimmy Page wiring scheme.

Stew-Mac Info on guitar parts and how they work.

http://www.jpbourgeois.org/guitar/microsbis.htm- Many really interesting passive wiring mods. Check these out!
*NOTE: Special thanks to Baconfish for finding where this page had been relocated!

http://guitarelectronics.zoovy.com/...iringresources/- Wiring resources.

1728.org (the .com domain was stolen)- Many neat diagrams of unconventional wiring schemes and how some parts work.

Guitar Nucleus- Some schemes for a few individual guitars.

GuitarNuts- Lots of useful info.

And let's not forget Google, for God's sake.
http://www.google.com/

COMING SOON: Give me ideas.

NOTICE: This thread is and shall remain a work in progress. If you see something that's not here and should be, tell me and I'll add it in. If you find broken images or dead links, PLEASE PM ME so I can fix them!

Special thanks go to (in no particular order):
MonkeyLink07
james4
cedricsmods
zakkwyldefan79
bellerophon
wiliscool
blandguitar
SomeoneYouKnew

For their help. Cheers, guys

Invader Jim

Before you do any of the troubleshooting tips listed here, rule out the obvious: test different cables, guitars, and amps to see if the problem lies in these. Also be sure to check the batteries. If the problem persists, then keep reading.

I want/need to learn how to solder. Any tutorials?

http://www.instructables.com/id/How-to-solder/

My guitar's output is really low/makes intermittent sound when I wiggle the jack or volume pot.
It could be one of several things. If it cuts in and out when you wiggle or turn the volume pot, then that pot is dead and needs to be replaced. If the same happens when you mess with the jack, then the jack is defective and should be replaced. Another cause, though less probable, is there's a component or wire shorting to ground and thus killing your signal. You might also just have crap soldering. A word about that...

You'd be surprised at how much bad soldering affects the performance of a circuit. If a solder joint is bad, then it has some resistance. Since these "resistors" are scattered all over, they make lots of series and parallel circuits with the other components. Bad soldering can also make accidental diodes. Diodes always have a forward voltage drop, meaning if the voltage is the wrong polarity or isn't high enough, these "diodes" won't even pass any current. If it does manage to pass current, the AC audio signal will be turned into a string of partially-rectified DC pulses, which might have a hard time getting past the coupling caps in pedals and amps.

All series circuits are voltage dividers, and the largest voltage is always found across the largest resistance. Just for fun, draw a wiring diagram and throw in a bunch of tiny value resistors, then do some Ohm's Law. Those tiny values can have a huge effect on the voltages in that circuit. Wires have ultra-low resistances and bad solder joints have far greater resistances. This means that those bad joints have far greater voltages across them than are in the actual wire (see the first sentence of this paragraph).

I just rewired my guitar and now there is a loud, constant buzzing and when I touch metal the buzzing gets worse.
You might have swapped the jack wires by accident. The lug connected to the inner circular part is the ground. The other lug is hot.

My guitar buzzes, but the buzzing stops/is reduced when I touch the strings or other metal parts.
Relax, it's normal.
Are you sure?
YES. But if you think otherwise, read through this thread.

Can I mix active and passive pickups?
This is from EMG's website:

"It is possible to mix EMGs with passive pickups.
There are three possible wiring configurations; one is better than the other two.

1. Use the high impedance (250K-500K) volume and tone controls.
The problem is that the high impedance controls act more like a switch to the EMG's [either Full Volume or No Volume].
The passive pickups, however, will work fine.
If you have a guitar with two pickups and two volume pots, with a three-way switch, there is another alternative.
Use the 25K pots for the EMG, and the 250K or 500k pots for the passive pickup.
This way you can use one or the other with no adverse affects,
but with the switch in the middle position the passive pickup will have reduced gain and response.

2. Use the low-impedance (25K) volume and tone controls provided with the EMG's.
The problem here is that the passive pickups will suffer a reduction in gain and loss of high-frequency response.

3. This is the best alternative.
Install an EMG-PA-2 on the passive pickups. There are two benefits to doing this.
With the trimpot on the PA-2, you can adjust the gain of the passive pickups to match the EMG's.
The PA-2 acts as an impedance matching device so you can use the low-impedance EMG controls (25K) without affecting the tone
of the passive pickups.
You will also be able to use other EMG accessory circuits such as the SPC, RPC, EXB, EXG, etc.
For this application, we recommend ordering the PA-2 without the switch for easy installation on the inside of a guitar."

Can I mix actives and passives without buying EMGs stuff?
Yeah, but I advise against it. It's expensive (lots of pots and switches), complicated (pots and switches), and in my opinion more trouble than it's worth (again, pots and switches). If you REALLY want to cheap out and ignore EMG's advice, post and someone might make you a diagram. We don't like making diagrams unless we just have to, so hopefully you can follow written instructions...

What kind of wire should I use for wiring my guitar and where can I get it?
You don't really need anything special. Smallbearelec.com and radioshack sell spools of wire. Look for something around 20-24awg. 22awg is ideal. You can either use shielded, solid core, or regular stranded wire. Obviously, shielded wire can help with noise. Solid core is easier to work with b/c you don't have to twist and tin it, but it can break inside the insulation if handled roughly.

Can/should I wind my own pickups?
The supplies and winder are not cheap, and the wire (~42awg) is literally hair-thin and very fragile. You will waste alot of money and ALOT of wire before you get a pup that sounds even passable, much less comparable to DiMarzio, Duncan, or one of our resident custom pickup makers, like nuthinbuttrubl8 or CorduroyEW. You should start slow; get an old junker pickup that you can cut the coil out of and use the bobbin. Make a winder yourself (or buy one if you have $300 to piss away) and practice with thread. Then get a small spool of magnet wire and try it out. Only start using magnet wire when you have a perfect feel for your winder and how it performs, and even then you should start slower than you would normally. Talk to any of the resident pickup winders to learn more.

I have an unknown pickup. How can I figure out which wires do what?
It's pretty easy.

Say you have 4 wires; A, B, C, and D.

Measure the resistance between all of them.

Say:
A+B=12k and A+D=6k. Then A and D are one coil. C and B are the other.

Now set the DMM to DC volts and get something magnetic, like a screwdriver. Lay it onto the pole pieces of, say, the North coil and move it around. If you get nothing on A and D, that means C and B are the North coil. A and D are the South. If the voltage goes negative, then swap the wires. The wire on the red lead is hot for that coil.

Say you have only 3 wires; A, B, and C.

Measure the resistance between all of them.

Say:
A+B=12k, A+C=6k, and B+C=6k. A and C are one coil and B and C are the other, meaning wire C is the tap because it is common to both coils.

Ground it to split the coils; the remaining 'on' coil is determined by which wire is grounded with the tap. If the pickup ground and the tap are grounded, one coil remains on. If you ground the pickup hot and tap, the other coil stays active. Use this info to make sure the pickups in your HSS or HSH configuration are in phase when selecting the single and humbucker/split humbucker. Wiring the tap to hot and the pickup's hot to ground will put the coils in parallel.

Figuring out which wires go to which coil is the same as with 4-wire.

I have an HH guitar with 2 volumes [and other stuff maybe] and 1 pot affects both pickups. WTF?
This is normal for LP style wiring. Try swapping the wires on the 2nd and 3rd lugs of each volume pot (looking at the pot from the front of the guitar). If that doesn't work, try changing the volumes to linear pots as well.

My volume or tone pot sounds scratchy/acts funny. Should I replace it?
Yes. A scratchy pot means it is either dirty or worn. Either way, it's a sign of a cheap/aging pot. It's best to replace it now before it causes problems down the road.

Do I have to have F-spaced pups for my tremolo bridge? Does pole piece spacing make a difference?
No to both. I have a guitar with rails (Peavey Horizon), had a guitar with properly spaced pups (Kaman GTX33), and had a guitar whose pups didn't match at all. There was no difference in performance. It's all about aesthetics.

Is it possible to convert a two-conductor pickup to 3- or 4-conductor?
Yes. Go here: http://www.ultimate-guitar.com/foru...d.php?t=1144316


More to come, when I think of more questions...

Invader Jim

Here is a clipboard of switches, pickups, etc. that you can save to your computer and use to better illustrate your own diagrams, since most of you are quite MSPaint challenged. :P

Switches

Now I'm going to explain how typical garden-variety switches work (this pic should be pretty self-explanatory, actually). An important note: On a toggle switch, when the lever is down the poles connect to the upper throws and vice-versa. So if the lever is pointing one direction, the poles connect the opposite throws. It's kinda counter-intuitive. If you are unsure, just use an ohm meter to see for sure.



And now for the switches that are mainly only used in guitars.

http://i41.tinypic.com/5b5um8.jpg

This is the inside of a typical Strat-style PCB blade switch. They are classified as DP3T for 3-ways and DP5T for 5-ways. 3-ways and 5-ways are identical; 5-ways just have more detents.

The solid traces in the inner part of the switch are the poles. They are common to all the throws. The outer traces (the ones divided into 3) are the throws. The throws are connected to their respective poles via the leaves of the lever section (pictured at left).

In standard guitar wiring practice, the two poles are connected and sent on their merry way. That is how the tone pots get connected to their respective pickups (except master tones, which are paralleling the pickups via the volume pot). Note that the 2nd pole is not actually needed for the tone pots. You can get away with only using "half" the switch. Just wire the tone pots directly to the switch lugs of the pickups you want them to control. This frees up the other half of the switch for other wiring stuffs (like auto-splitting a bridge humbucker in position 2 of a 5-way switch).

http://i44.tinypic.com/11hdvua.jpg

As you can see from the labels in the left pic, whichever trace is connected to the circuit on one side, the opposite trace is connected on the other side (as illustrated by the red line in the left pic).

In the left pic the switch is selecting the bridge pickup and anything connected to the other pole, like a tone pot.

In the right pic we see what happens when a 5-way is in the second position, where the bridge and middle pickups would be selected. Note that the pickups are in parallel.

http://www.epiphone.com/images/N_LPfeat3.jpg

This is an LP-style 3-way toggle switch, also called a skeleton switch due to its open construction. It is classified as SPDT on/on/on. These are really only used with two pickups (usually humbuckers) to select one, both, or the other. These are used instead of 3-way blade switches because they are much smaller and fit in tight control cavities.

The way they operate is simple. A plastic peg connected to the lever moves a leaf off of the pole when moved in either extreme direction. The two leaves are always wanting to contact the poles due to their spring-action design. So when the lever is in the middle position, the peg doesn't lift any leaves so they both connect to the pole. Note that the pickups are in parallel.



Popular opinion is that these types of switches suffer from a major design flaw: they rely totally on the spring action of the leaves to operate properly. A common cause for the failure of a circuit that uses this switch is that the leaves' spring action has worn out so they are only making intermittent contact with the poles.

You can fix this quite easily; just put the lever in the middle position and bend the failing leaf back into contact with the pole. Test it with an ohm meter to see if the plastic peg still lifts the leaf. This should merely be considered a temporary fix, though. Getting a new switch is best. One way to prevent the premature failure of this switch is to leave it in the middle position when you are not playing the guitar. This helps save the spring action of the leaves so they last that much longer.

http://i42.tinypic.com/xm8u91.jpg

This is a 'traditional' strat lever switch. On the left is a 3-way from a 1960 homemade tele and on the right is a new 5-way. Notice how the older one is taller. These old switches will not fit into a modern guitar without doing some routing. I put that into my Affinity and had to chisel out some wood. I actually removed ALL the wood, leaving just the extremely thick paint. So if you find an old 3-way like this lying around, it probably won't fit into your guitar. Please don't ruin your guitar's paint job like I did trying to find out.

Ok, so that's out of the way... I'm going to be referring to the 5-way from here on unless noted.

http://i43.tinypic.com/2rqc4m9.jpg

You see how there's a contact that touches the rail of the wiper? That's the Common (pole) lug. See the blade on the end of the rail? That is the throw. Whatever lug(s) it touches is connected to the pole. Here it is in position 2 (mid+bridge). Note that the two lugs are in parallel. Here it is in position 5 (neck):

http://i40.tinypic.com/e7gc5e.jpg

And here is the 3-way when caught between detents, for the 2 and 4 positions. You'll notice that the wiper on the 3-way is slightly narrower than on the 5-way, but it is still just wide enough to jumper both of these lugs:

http://i42.tinypic.com/295a2o0.jpg

Until about '77, Fender only used 3-ways in their strats. You may have heard about people (like Hendrix) sticking toothpicks or matchsticks in the slot to hold the switch between detents to get these 'new, never-before-heard' (lol) sounds (which were out-of-phase*, if I remember reading correctly). Also, these positions weren't hum-canceling back then. Strats didn't use RWRP middle pickups until the implementation of 5-ways*

*Correct me if I'm wrong on these.

Other than these mechanical differences, they are exactly like the PCB switches I talked about earlier.

Here's a comparison diagram of the two switches.

MonkeyLink07:
It may almost be easier to look at the switch in halves.

You have your common, and 3 poles, your common is lug 4.

1 2 3 4

In position one, it connects the common (4) with 1, position 2 with 2 and in position 3 with 3.

So you have 3 possible connections, 1 and 4, 2 and 4, and 3 and 4.

If you wired a battery up to 4, and 3 light bulbs, labeled 1, 2, and 3, on lugs 1, 2, and 3, in that position, the power would be connected to that light bulb and it would work.

But then, since you actually have 8 lugs, you just have 2 of those 4 lug switches, they just are controlled by the same lever. Completely independent electrically, but will be connected to their own poles based on the same mechanical action.

The only difference in a 5 way is that it has two extra positions between 1 and 2 and 2 and 3. This is easily thought of by what they used to do before they had the 5 ways. They would take a toothpick or something small and jam the switch halfway between positions, so that it connects the things that would be active in both positions 1 and position 2.

So all they did was add an extra notch to the switch so it would stop "in between" activating both contacts, and boom, 3 way into 5 way. If we went back to the light bulb analogy, in position "1 1/2" it would have both light bulb 1 and 2 on, and in position "2 1/2" it would have light bulb 2 and 3 on. Because they didn't want to say "Position 1 1/2" or "Position 2 1/2" they just moved the naming over, calling what was position 2 position 3, calling what was position 3 position 5 and throwing in the extra positions as positions 2 and 4.

Up next: Potentiometers. Or capacitors. Idk yet.

Invader Jim

Anyone with severe noise problems should read through this thread.

A version of the treble bleed mod:
http://i44.tinypic.com/zlu70y.png
SomeoneYouKnew: One of the problems with a parallel resistor is that it changes the taper of the pot. When you first start rolling down the volume, it won't change as much as it would without the resistor. If that's a problem for you, use a somewhat larger resistor. In the example shown, I would use a 470k for R1. It's a personal taste sort of thing. Scale the values down by 1/2 for a 250k pot, of course.

The Fender Greasebucket tone control:
http://www.tdpri.com/telephoto/data...et_Circuits.jpg
This circuit is supposed to cut high frequencies WITHOUT "adding" bass. Mostly it has to do with that 4k7 resistor in series with the pot. That makes it where it'll never get to 0. In other words, you can do almost the same thing by simply not turning the tone all the way down (the cap on the wiper complicates things a bit though. It forms a parallel RLC circuit with the pickups and I really don't want to get into that).

EDIT: I tried the circuit and I was quite surprised that it actually does what they say it does. I recommend it to anyone.

Wiring a killswitch and an LED where the LED is on while the switch is pressed:
http://i40.tinypic.com/fwlzd0.gif
The In/Out labels are meaningless since the jacks are in parallel. The switch is wired so that the battery is only connected while the switch is pressed, eliminating the need for a stereo jack.

Pin-out for the Ibanez VLX53 switches:
http://i207.photobucket.com/albums/...LX53Innards.jpg

Wiring the second tone pot in a strat as a BASS CUT instead of a second TREBLE CUT:
http://i41.tinypic.com/14io9hf.jpg
There is a subtle volume drop at 10 [most bass cut]. YMMV.

More Jimmy Page mods:
http://www.deaf-eddie.net/drawings/jp-lp.jpg

Common switch pin-outs:
http://www.deaf-eddie.net/drawings/5-ways.jpg

A pin-out for Aria switches (compliments of stuartm65):
http://i38.photobucket.com/albums/e...tm65/switch.jpg

How to wire an effect pedal into your guitar:
http://i38.tinypic.com/10z9umr.gif

Wiring LEDs for whatever reason you see fit:
http://i48.tinypic.com/2848j5.jpg
Lower resistor value=brighter. Don't go much lower than 220Ω.

This is how my '60s Conrad is wired. Use this as inspirado or references to similar schemes you want to implement.
http://i47.tinypic.com/30codb7.jpg
2 pickups, 1 volume, 1 tone, 2 pickup switches, and a different version of a killswitch.

This is how to wire a DP6T rotary switch for 3 pickups to get all the standard 5-way lever switch settings (and in order!) plus the Neck and Bridge pickups activated.
http://farm4.static.flickr.com/3274...e314d6dba_o.gif
The numbers along the top are the positions and the numbers on the sides are the poles. The O's are the switch lugs.

This is a schematic I saw in a home-made semi-hollow Tele-style dated 1960. Use this as inspirado or references to similar schemes you want to implement.
http://i47.tinypic.com/69nhgo.jpg
2 pickups, 2 volumes, 2 tones, 3-way blade switch. You may want to leave out the 33k resistors; they reduce output quite a bit.

This is how my 1963 Hofner 172 is wired. Use this as inspirado or references to similar schemes you want to implement.
http://profile.ultimate-guitar.com/...914_image_0.GIF
2 pickups, 2 volumes, Rhythm/Solo switch, Bass On switch, Treble On switch.

Invader Jim

Thanks to MonkeyLink07 for this part. I will expand on it in the future.

This is a Rotary Switch:


Rotary switches come in many different sizes, and are classified like normal toggle switches with Poles and Throws. The Pole can be thought of as a common terminal. In any position, this terminal will always be connected to another terminal. Which terminal is is connected to is determined by the position and is called the Throw. So in position 1, throw 1 and the common terminal will be connected. In position 2, throw 2 and the common terminal will be connected, and so on.

This switch is a 4 Pole, 6 Throw, with 4 common terminals and each of those common terminals having 6 throws. These Poles are all seperate and no connections are made between different poles. It can be thought of as 4 different 1 Pole 6 Throw switches if you like, but all controlled with one knob.

Here is a pinout of the 4P6T switch. CT stands for Common Terminal:


And the schematic version of one of the poles, for a better visual concept.


Also, let's cover Super Switches. A super switch is a 4P5T switch in a 5 way blade style. They work on the same basic throw and pole system as a rotary switch.

This is a Super Switch:

Invader Jim

Electricity doesn't have to make it into the earth to be a complete circuit. Pick up your MP3 player, or any battery powered device. Plus everything that uses a power transformer with a 2-wire line cord; none of these are actually grounded. What people call the ground of a circuit is ACTUALLY supposed to be called the return. Another tidbit, the return (aka ground) can usually also be thought of as "oblivion". The only way you can truly call it ground in a circuit is if it is actually connected to the earth's ground.

That ground symbol used in schematics shouldn't be used unless it refers to the earth ground, but hey. It's convention. It's wrong, but it's convention. The right symbol to use would be what we call the "chassis ground" symbol. That's what should be used to mean a common circuit return.

All transformers (except variable ones) provide voltage isolation. What I mean by 'voltage isolation' is this: If you look at the schematic symbol for a transformer (figure A in this pic), you'll see 2 coils of wire on each side of some vertical lines (usually 2) that represent an iron core. This is a wonderful symbol because it shows graphically exactly what happens in the transformer. The 2 coils of wire are completely isolated from each other (except of course for leakage current, since there is no such thing as a perfect insulator, but this leakage current can be totally ignored).

So your amp isn't actually grounded to the earth unless it has a 3-prong grounding line cord. The neutral and ground wires of your house are connected right inside the main breaker panel ('check local listings' for UK wiring). The reason for this is because the NEC doesn't want a single wire doing double-duty as a neutral and ground wire (actually a recent change in the law requires the neutral and ground to be connected at the kW/hr meter outside the house, not in the breaker panel; this makes them seem less like a single wire). In the WWII era, copper was rationed so houses were wired with a hot and neutral wire and the ground prong (if the outlet even had one) was pig-tailed to the neutral. It works just the same.

The 2 wires of the line cord are directly connected to the primary of the PT (excluding the fuse and power switch). If there wasn't that 3rd wire from a grounding line cord, that is where the earth's ground connection stops.

Since modern amp line cords have that third wire connected directly to the chassis (and the chassis is connected to the circuit's return), then the whole amp actually IS grounded. You can run an amp with or without the chassis earth-grounded; you wouldn't know the difference (sometimes lifting the chassis ground can reduce noise a bit, though this is ill-advised). The reason they use the third wire is for safety* (yeah right). Should you plug into an improperly wired outlet, or the chassis somehow become live with an appreciable voltage, it would short the hot and neutral (via the ground wire) together and blow the amp's fuse and/or the circuit breaker in your house.

In fact, if it was a 100% guarantee that all outlets in the country were wired properly, there'd be no need for that third wire in the plug (as long as the plug was polarized). You could just wire the neutral directly to the chassis/circuit return.

Up until the mid-60s this is exactly what everyone did. But this isn't a perfect world so that is a horribly unsafe thing to do (especially since they didn't have polarized plugs yet). Without a polarized plug, the circuit would work just fine either way but plug in one way and the chassis would be hot with the full 120v line voltage when the power switch was on. Turn the plug around and then the chassis would be live with 120v when the power switch was off (because the chassis was connected to the hot wire through the series-connected tube heaters of cheap old table radios).

*Here's why I disagree with how "safe" it really is. Why are line-operated appliances so dangerous? Because if you touch the wrong wire you get shocked. Duh. Why do you get shocked? Because you are a path to ground.

The line current flows from the hot wire and wants to get back to the neutral wire (which is grounded). Since you are a path to ground, touching the hot wire gives the current a place to go (through your body) to get back to the neutral wire. Touching the neutral wire does nothing at all since it and you are at the same potential.

If the neutral was not grounded, the only way you could get shocked is by touching both the hot and neutral wires at the same time. Touching either wire by itself would do absolutely nothing because the ground is no longer part of the circuit, so your body (a constant path to ground) is electrically isolated from both wires. Touching both wires at the same time completes the circuit from the hot to the neutral. The ground would be irrelevant.


Other interesting stuff

Sometimes we need to get around the fact that the neutral is grounded in order to maximize safety or use a piece of test gear properly. To do this we plug into an isolation transformer. An isolation transformer is nothing more than a regular power transformer that has the same number of turns of wire on the secondary as the primary; put 120v in, get 120v out (actually there are slightly more turns on the secondary to make up for efficiency losses). Since all non-variable transformers provide voltage isolation, there is no way for either wire to shock you (unless you grab both at once) since neither is connected to the ground (or anything else).

If the neutral was not grounded, there wouldn't be any need to use an isolation power transformer and all this trouble could be avoided. The only reason they decided to ground the neutral in the first place was too help protect equipment; not people.

In case you were wondering about variable transformers, here's a quick rundown. Variable transformers (auto-transformers, more commonly called Variacs) do not provide voltage isolation because they are made of only 1 coil of wire wound on a toroidal (donut-shaped) core; the input and output share a wire (refer back to this diagram, figures B and C). They look like very large wire-wound potentiometers with 3 lugs and at least 1 more for a tap. They have 1 lug on each end of the coil, a lug for the wiper, and 1 for a tap near the end of the coil. The purpose of the tap is to provide a boosted output voltage, higher than the full input voltage. The boosted voltage isn't alot because it gets unstable if it gets too high. About the most you can get with a 120v input is 140v out. Smaller ones (like the one shown in the pic) will only give 132v output.

Isolation transformers and Variacs were intended as service aids in electronic repair shops back in the good old days. Every shop tech worth his salt had one, and usually they were put into homebrew boxes along with a dim-bulb tester as a single unit. They also make excellent variable AC/DC bench power supplies as they are far superior to controlling the voltage with a potentiometer. For even relatively low voltages and currents, you need a high-power potentiometer, which are uncommon, expensive, and get hot in normal operation. A Variac has no problem supplying several amps of current and at mains voltages.

A dim-bulb tester is a device that uses incandescent light bulbs of various wattages in series with the mains to current-limit the power going to the appliance, allowing you to safely power it up with a shorted power transformer, or a short across the mains somewhere else in the circuit.

Under normal conditions the bulb will barely light, if at all, because the cold resistance of the filamant is only a couple of ohms (as the filament heats up, the resistance increases to hundreds of ohms). If the mains is shorted in some way, the bulb will protect the appliance because it is the first thing the line cord sees, so a short after the bulb is nothing more than the same circuit for the lights in your house (essentially, anyway); the bulb becomes the load, dropping most or all of the voltage across itself instead of the appliance under test (which is shorted). Remember when I said the largest voltage is always across the largest resistance? Means a little more to you now, doesn't it?

The only thing I would change in the diagram in the link above is to put the power switch AFTER the bulb. Should something happen with the switch, the bulb would prevent shorts across the mains (the same reason you should always wire fuses and circuit breakers BEFORE the power switch).

chuckflan333

Due to a lack of space above and no one noticing this as a link. I (zakkwyldefan79) am hijacking Chuck's post so I can make this an image. Now maybe people will notice it.

A list of pickup wire color codes:

__________________

Gear

-MintSauce-

Reserved for myself, in case I have anything to bring to the table.

Edit: Also, great idea. This should be stickied.

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Current builds and progress
Ash Superstrat (carved): Project complete,
Mahogany Random Star: fretting and final neck shaping,
Unlimited 2012 - SF24: body and neck rough work.

tona_107

The birth of a legend.
I have some sites I'll post in a sec.

http://www.beavisaudio.com/projects/
http://www.montagar.com/~patj/tubedist.gif
http://www.diyguitaramp.com/tech.html
http://diycustomamps.com/index.htm
http://www.schematicheaven.com/index_HTML.htm

thischarmingsam

Errr are general wiring q's ok? I'll delete this if not. I got this:



off the lovely people at Irongear, but I don't know where to ground it, is just on the side of the pots ok?

chuckflan333

Ultimate wiring thread maybe?

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Gear

Invader Jim

Minibrowny: Wire it as-is and attatch a wire from the bridge to the case of a pot. Ground all pot casings to the sleeve of the jack.

thischarmingsam

Ahhhh thank you, I get it now I've never really understood them before. Cheers!

EDIT: Is it wired to the bridge on all guitars? I got a wraparound so would I just route out a small hole underneath and solder it to the bottom of the bridge?

Invader Jim

There should be a hole drilled into one of the shafts for the bridge post.

Protip: Editing a post doesn't bump the thread. Sorry for the late reply.

Invader Jim

Second post updated.

ezlntrooper

wow! that last diagram on the 2nd post is crazy. Great idea too!

Quick question, if there was no single coil in that diagram, would the switch need to be adjusted in any way? would it need a three way switch??

__________________
A man said to the universe:
"Sir, I exist!"
"However," replied the universe,
"The fact has not created in me
A sense of obligation."

STOP MODERN DAY SLAVERY

Invader Jim

You could change it, or you could come up with funky things to do with it. I think you can wire a standard 5-way to auto-split two humbuckers. I'd have to sit down and think. I know you can auto-slpit the humbucker in a HSS guitar. Simple to do, too.

Absent Mind

Sweet thread, yeah I'm getting pretty tired of all the repetitive $hit. UG = your personal search engine *sigh*

Also this wont be stickied, no 'ultimate thread' will ever be, there are too many, it takes up too much room. Although an 'ultimate ultimate' thread would be good, as there is no index of all the unstickied threads like 18V, killswitch, pedal mod, etc and the current stickies are old and not updated by the mods.

Most wiring diagram threads could just be answered by going to the Seymour Duncan website, they have a ton of diagrams there, people just dont look...

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snot_foster25

I have a question that's just to satisfy my curiosity. It's more of an installation question than a wiring question, but I thought I'd ask here and save some space instead of making a relatively pointless thread about it.

On a Les Paul or something similiar, how do you ground to the bridge? I know there's some kind of shaft leading from the control cavity, but if I needed to reground to the bridge, how would I do that?

Seems like a kind of impossible task, as though that's something that'd get done before the maple cap was put on. This is just something that I think might be a problem if I ever try to repair my LP with a broken headstock.

Sorry if this isn't the place for this question, too.