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[veganempire]

Hi, I've tried to do the voltage  drop crash bend on my casio sa-1, in the same way that's showed in the tips section. I've soldered a 1K log pot ,but when I turn it slightly the sound dies. No weird sounds, just dies. What I'm doing wrong? Sorry If my english sucks, but I'm spanish. Thank you!

[Signal:Noise]

The obvious one is try a lower value pot. After that maybe try a log rather than lin pot, but if that doesn't work then I'm afraid i'm stuck.

[catweazle]

If the circuit needs a lot of amperes then you can try the following...
Get a  LM317  (linear adjustable voltage regulator 1.2V..37V with up to 1.5 Ampere)



Datasheet:
http://cache.national.com/ds/LM/LM117.pdf

... and they are very cheap

(the input voltage of the LM317/LM117 can be in the range of 5V..38V)

[veganempire]

I've tried some pots of high and low values, lineal and logaritmic, but it doesn't work! Maybe it's because I use batteries?

[catweazle]

try the following ... (simple voltage divider)



http://www.geocities.com/franzglaser/txt/vdiv.html

this should work - I hope

[catweazle]

Important thing about the potentiometer:
the value isn't critical but should not be lower than 10 kilo Ohms.
The Pot is parallel to the batteries, so at 6Volt  0.6mA  flows all the time
Higher Pot values decreases currentflow 

Formula  I=U/R

 I=current in ampere  (1mA = 1/1000 Ampere)
 U=input voltage
 R=potentiometer resistance in Ohm (10k=10000 Ohms)

But U should be careful with things connected that needs more power (driving a SK-8 for example)
The potentiometer will be blown (overheat and smokes away) !

Formula  P=U*I

 P = power in watts
 U = input voltage
 I = current needed from connected circuit in ampere

A normal pot can hold 1/4Watt (0.25 Watt) ->    I=P/U   (example U=6V then you can drive up to 40mA)   

If you want to drive a Keyboard or other big things better use the LM317 I described above (up to 1.5A)


You can left the capacitor C1 in the voltage devider schematic (it's only needed if the driven circuit hasn't one)