How do I wire an LED to the switch of an 'Active'Circuit?

[JTM45]

Hi Guys!
           As you can probably tell from my post title,I am an electronic cripple and this is my first post here.I'm after some information about 'Onboard Guitar Electronics'.Most of the 'guitar people' I've asked for help don't seem to have a clue about much more than pickup connection(myself included!).
           What I want to do is to be able to connect an LED so that it will illuminate when I flick the switch to operate an 'Active-Boost' circuit on a guitar.It would preferably be switched on by the same 'Mini-toggle' type switch that I would use to switch the Active-Boost circuit,but I want to be sure that it won't actually effect the Active Circuit.
           I'd also like to use a similar method to enable me to have LEDs that would light when I selected each pickup on the guitar(one LED for each of 2 or 3 pickups).
           I have been told that I need to use '3PDT' mini-toggle switches,but this means nothing to me(Sorry!).I'd be HUGELY greatful to anyone who can help me out with this electronic dilemma.Maybe I can start to learn something at the same time too.That would be great as I've always had an 'LED fetish' but never had the knowledge to do much more than burn them out with an oversized battery,lol!
          Please help me!!!! I will be eternally greatful.Maybe I can even get into making some wicked effects as well then with my newly acquired knowledge.
           Thanks for your tolerance Guys.We've all gotta' start somewhere,lol.All the Best+Many Thanks.....................JTM45!!!!!!!!!!!!

[NaBo]

Hello, welcome to the forum!

You'll find a lot of information on these sites that will help you figure things out:

//www.generalguitargadgets.com
//www.tonepad.com
//www.geofex.com
//www.muzique.com

The FAQ sections on these sites are absolutely priceless.

I suggest definitely looking at a few of the wiring diagrams at General Guitar Gadgets (GGG) or tonepad, and this article on geofex to get an understanding of how switching works: http://www.geofex.com/Article_Folders/bypass/bypass.htm

To add an indicator LED for the booster in your guitar, you should use a 3PDT toggle, "three-pole, double-throw".  It's a switch with 3 sets of 3 lugs.  Your booster circuit (store-bought or homemade?) probably uses a DPDT, "double-pole, double-throw", switch (2 sets of 3 lugs).  It's possible to use some clever circuits to use this kind of switch to light an led as well, but this will take up a bit more room and won't be as easy to wrap your head around just yet.

As for your guitar pickup indicators, you need more information.  What kind of switching scheme does your guitar use right now?  A rotary switch? Toggles?  What kind?  How are they wired? ... etc...  you might want to leave this project aside til you get your feet wet a bit.

LEDs require a current limiting resistor (usually 4.7 kilohms for common types) between the positive end of the battery and the cathode end of the LED (usually the long lead).  You'll learn about that too.

Take your time and read up on everything you can, use the search function on this forum (there's some incredibly useful information here!).  A word of advice: some of the salty old dogs of the forum () get a little peaved when the same questions get asked over and over, so at least make an effort to locate the information you need on one of the great sites I mentioned (theres more out there too!) or on this forum.  I'm not quite old or salty yet, but I've garnered at least some basic knowledge and I'd be happy to help go over anything you're unsure of at first.  Feel free to pm me.

P.S.... I completely understand your fixation with LEDs.  Most people around here would... It's why we buy 3PDT switches and 50 cent 5mm ultra bright water-clear LED's, and 75 cent chrome bezels... It just looks too sweet  

[JTM45]

Many Thanks 'Nabo'!
                            You've restored my faith in the human-race!(and in Forums for that matter).You've given me more information and help in that one reply than I managed to get from about 10 different Forums.Plenty of stuff to be going on with there anyway.
           Thanks for your offer of further help too.I may well take you up on that.I'm bound to encounter problems along the way.The guitar is one that I'm putting together as a project.I've never believed in doing things by-halves so it's turning into a 'dream-project' sort of guitar.It's definitely not going to be ordinary.I've got an Hollow Aluminum Tele shaped body coming and a really smart Flame-maple neck with an Ebony board being made for me.I'm also hoping to fit a 'Fishman' Piezo Bridge to it and I'm still deciding on the pickups.That's why I've gotta' have the electronics all nicely sorted too.Oh,the 'Active-Boost Circuit' is coming from 'Neal Moser',the guy who did a lot of the early BC Rich guitars.It's  exactly the same circuit as those used in the top of the range BC Rich guitars,so it should be a good one.Once I've got all of the parts I can really get to work on the electronics(THEN I'll really need some help,lol).
         I've got the added problem of living in the UK(Wales),which isn't a problem in itself,but all the parts are having to be ordered from the US(mainly because the prices of guitar stuff is Ridiculous over here!).
         Anyway,Thanks again and I'll be back in touch soon.I'm gonna' have a look at some of those sites in the meantime to see if I can try and soak some of it up.Talk to you soon!
      All the Best!.............................JTM45!!!!!!!!!!!!!!!!!!

[NaBo]

Wow!  Sounds like a VERY cool project.  You'll have to post pics and sound samples here when its finished.

As for the 3PDT switch, it's a 2 position switch.  The middle lug of each column connects to the lug directly above or below it.  Look at this diagram from GGG for reference, I added little diagrams of the connections in both positions of the switch: http://img.photobucket.com/albums/v515/Nabotics/3PDTWiring.gif... in this case, position "1" is the "off" position, or "bypassed" position, and position 2 is the "on" position.

As it is right now, your booster probably uses a DPDT switch (omit lugs 1 2 and 3), wired one of these ways: http://www.muzique.com/schem/dpdt.gif The top diagram here corresponds to the first link, just flipped around.  Either way, the wiring is such that the guitar signal is directed by the switch to the output jack in one position, and in the other position it connects the input jack to the circuit board's input and the circuit board's output to the output jack.

Anyways, the 3PDT has an extra row of lugs that you can use to light an LED when the switch is in the "on" position.  The ground from the LED is connected to lug 2.  In the on postion, lug 2 connects to lug 3, which connects to the board grounds, so electricity will flow through the LED.  When the switch is in the "bypass" position, lug 2 is connected to lug 1, which is connected to nothing, so the circuit is incomplete and the LED will be off.

You can think of the LED as always being connected to the positive end of the battery, and being connected to the negative end of it by the switch.

PHEWF!  Let me know if that helps any!

[JTM45]

That all looks Fu*kin' great NaBo!!!!
                        I haven't quite had a chance to fully absorb it all yet but I had a look at the 'Photobucket' link diagram(squinted a lot trying to read it for 5 mins,then realised I could enlarge the picture,duh! Everything then became a lot clearer,lol.).
       I'm sure by the time I've had a chance to study all the information more thoroughly I should have the full idea.I can allready understand its basic theory,so all of your information has helped a great deal.You must have a mine of info stored in your noggin,fairplay!
       I'm still waiting for my body and neck to arrive but they should be with me within the next couple of weeks I hope.I can start getting all of the other bits and pieces togehter then.I've sourced most of it so it's just a case of buying most of it.I wanted to wait until I've got the body so I can be sure of measurements and stuff.There's no problem with having somewhere to fit any circuit-boards and bits as the body is more or less hollow(it has a sort of 'support frame' inside).I just can't wait to start putting it all together!
       I've got a few guitars as it is(1979 Gibson Flying V,Gibson SG+a coupl of Ibanez guitars too)but I've always wanted to build a guitar to my specs with everything(well,most things)I want on it.I hope it turns out as cool as my ideas anyway!
       Thanks a Million for the help! It's totally appreciated and fully welcome! I hope you don't mind if I PM you again when I start moving things along a bit.I'm sure to need further help.All the Best!...........JTM45.