so i was thinking..  the guitar puts out ac wave forms...so what as long as u have decent output pickups.  u should put out around 180-300mv of power with your pickups..  so what if we were to rectify that.  using some small shotcky diodes.. and have say a 3V lithium bat pack on board for a jfet preamp circuit.. so what i was thinking is making a charging circuit that creates voltage as you play?? i know there is alot more to it than this. but worth thinking about..

now.. i have an x2n in my guitar. which is supposed to put out 510mv and i use at least 13's on it so surely i coudl get some sort of juice otu of it.. hmm mayve add an ultra small transformer from one of those camera flashers in a disposable camera.

hahahaha I was actaully thinking about the same thing last night...doubt the voltage is high enough though...

how about a self powered wah ? :-D

the lowest forward voltage drop for a schottky diode that I can find is 320mV.  You loose twice this in a full wave bridge.  Even if you had 1VAC (twice what you have!) coming out of your pickups you'd only end up with 0.25VDC.

And any current draw from the charging circuit would load the pickups down and the voltage would drop even further.

Perhaps better off having a solar panel on your guitar?  That way, when you play big stadiums with heaps of lights...

No, wait... a generator hooked up to your arm, so when you do the "windmill" move you're charging your battery?

Hook something up to your drummers bass pedal?

Sit on an excercise bike?

Wear lots of nylon?

I'm surprised no ones using phantom power for guitars.  Easy enough to convert it to a balanced system, and phantom is readily available from mixers and stand-alone units!

What about using this gizmo in a Wah-Wah to recharge a main battery used by many effects?


http://www.haimei.com/novelty/index.htm

Some old clocks have an electromagnetic driver to sustain the pendulum's movement, maybe something like that inside a guitar body could work the other way around.

or you could simply build passive pedals like my earth-saver boost, which was a custom transformer-based booster.  8^)  went over like a lead balloon... i think i sold 2.

i also made a one-off earth saver boost/octave, also with no battery.  transformers are nice for that kind of thing.  8^)

Quote from: zachary vexor you could simply build passive pedals like my earth-saver boost, which was a custom transformer-based booster.  8^)  went over like a lead balloon... i think i sold 2.

i also made a one-off earth saver boost/octave, also with no battery.  transformers are nice for that kind of thing.  8^)

zachary zepellin  anyone..???

sorry z just pickin with ya..  you don';t ahve  a pic of thist thing do ya i 2would like to see it.

I'd also like to see it, I remember talking to you a tiny bit about it a long time ago...

-Colin

....I put a wind up DC generator that I removed from one of those wind-up radios into a box with two 1.5 volt versions of that Olsen Fuzz.....it sounds interesting,but works o.k.......now if I can build a wind up Leslie cabinet/amp..........

FEW!  Glad I apologised in advanced yesterday... coz those calcs I gave were way off!   I did stumble accross an interesting circuit last night though.  No idea of the cap or diode values, no idea of the current requirements... but it's interesting nonetheless!


      ------------------->|---------------o
      |          |              |
     ---         -              |
2Vsec ---         ^              |
      |          |              |
      |          |              |   Vout = 3Vsec - 3Vdiode
      |---->|----|              |
      |          |              |
  -. ,-         ---            ---
   )|(          ---Vsec        ---3Vsec
   )|(           |              |
  -' '------------------------------------o

                   Half-wave voltage tripler


created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

One of the depressing things about formal training is that you sooner or later come face to face with the three laws of thermodynamics. The laws say in essence:
1. You can't win. (you can't get more out of something than you put in or is already in there)
2. You can't even break even. (friction, conduction, and other radiation losses eat up some of every energy transformation, so you lose some every time you do something with it)
3. You can calculate how bad it will be. (stuff about entropy, etc.)

Taken together, you have to put in enough energy to power whatever it is that you want to power, plus supply the losses in any transformation.

It is certainly possible to power pedals from a bicycle-driven generator. It is probably possible to run some pedals from a wah-style rocker that you whomp on continuously. It is unlikely, given the efficiency of electromechanical conversion at guitar pickups, that you could power even a single pedal from pickups. The pickups don't pick enough up from the strings, or the strings wouldn't ring like they do. Maybe a thousand guitarists and some pretty fancy circuitry might power one pedal, but I don't know even ten guitarists that can play in unison, so the human element might be the failing there. 8-)

Lots of people have tried to break one or more of the three laws, but these all qualify as something that Mother Nature has said is non-negotiable. Energy out is always equal to energy in (including stored energy) plus losses, and without really good efficiency, losses kill you.

Hmmm... thumbnailing the signal levels, you get 100mv from a guitar pickup from maybe a 5K impedance. With a matched load of 5K for best possible power transfer, you are getting 100mv*100mv/10K= 1*10-6 or 1uW out, of which half can be transferred to that 5K load. That's about the best you can do, if you can strum fast and hard enough to keep that 100mv going. Super humbuckers turn out maybe half a volt, but from a 20K impedance or so. No win there.

So you have half a microwatt to start with. Your pedal has to use less than that, and any losses subtract from the amount the pedal has to use.

You need to make the voltage at least ten times as large as the rectifier losses to get the efficiency of the rectifiers themselves to 90%. So even with schottky diodes, you need to step the voltage up to 6V or so for 0.3V drop schottky diodes (I'm assuming you want to full wave rectify and not throw away half the power there.) Might as well go all the way and step it up to 10-11V with a really ..good.. signal transformer that doesn't lose any of the highs, and produce 9V directly. Except that rectification is really only good for peaks, so you throw away about 3/4 of the power by rectifying only peaks. Lets say you now have 375nW at 9V and are not losing much elsewhere. Your pedal circuit can have 41nA to run on. That's about the leakage current of three or four diodes NOT conducting.

It won't run an indicator LED, either  8-)

well you know for every crazy scheme that willl work that i come up with i have to come up wiht one like this. or i wouldn't be mee..  but then again i did do something that is kind of hard on this forum i got everyone to think and not complain. lol

:? Well I believe I have one circuit lying around somewhere, that tried to take "free" energy. It was a super low current consumption led blinking circuit, and the idea was that the energy was taken from ac mains hum which is easily available in most places :wink: But I remember you needed ten meters long antenna for it. But current needed for the led blinker was something that a normal battery would last for years. Maybe you could take some mains hum signal from a guitar cord with two hot conductors and take the power to super low consumption led blinker from it. But you would need a battery for the rest circuit anyway. But maybe you *can* put a led to Z Vex eco pedal, or any passive design, without batteries using this kind of idea :roll:

There has been some circuits around for battery-less superbright led torch: take output from a stepper motor, rectify it and store the voltage in a big el cap. Few twists and led lights up for long time. Think they use similar in submarine boats :roll: Sure this could be used for wah...

[quote"Nasse"]Sure this could be used for wah...[/quote]


Yeah, and it'll build up your leg muscles at the same time!  Get good at playing at funk fusion tempos before attempting this!  My boss has built one of these, and it takes reasonable effort.  It does light for a long time, but at a dull glow, the useful light fades fairly quickly.  Perfect for those pesky blackouts!

you may not be able to get something for nothing, but you can get something for something.  here's a guts pic of my earth saver octave/boost showing the custom-designed transformer and the rest of the parts... 4 germanium diodes, a dpdt selector switch, dpdt stomp switch, one cap, and two jacks.  the thing had an enormous number of taps.  multiple humbucking coils, actually.  no battery!

http://acapella.harmony-central.com/forums/attachment.php?s=&postid=7187721

oh, and the outside.

http://acapella.harmony-central.com/forums/attachment.php?s=&postid=7187712

cool  i like that.. man.     al i need to know now is wehre is the sound sample.
and or how did it sound. and

THANK YOU MAN

well, in boost mode it was kind of funny.  it doubled the output of the guitar (amplitude was basically 2X) but the frequency response was horrible going straight from guitar to boost to amp.  the low-end was perfect, huge, but the treble really got lost.  turned single-coils into humbuckers.  however, and this is the funny part, if you used it after ANY non-true-bypass effect like a boss or ibanez, it sounded excellent... louder and clearer.  buffered-bypass effects have such low-output-impedance that they can drive transformer-based boosters quite well.  it was really creamy and natural sounding, of course, being just a transformer.

and the octave was similar to an octavia, not terribly loud, but very very pure and pretty.  it did the octave thing better than boost by itself.  the decay on the octave was quite dramatic... it would decay at an alarming rate if the guitar was plugged straight in.  like a damped bell.  still really pretty though.

sometime i'll make a sample.  my m-box isn't osX compatible yet... or at least i haven't installed the new software, which i must have around here somewhere.

cool man so the tranformer was like that of the octavia

yes, but instead of relying on a transistor-based boost driving the transformer, it was carefully designed to transfer as much energy as possible from the very poor high-impedance pickups (actually varying by frequency from 5k to about 10 megs) of a guitar into a set of voltage-losing germanium diodes and onto the hell the horrible input impedance of a typical amp (1 meg).  why they don't make 5 or 10 meg input impedance amps is way beyond me.  they would sound so much nicer, although they'd quickly reveal the flaws in your cables and connections.

cool man