[sdiy] [AH] TB-303 Problems and Questions

[Amos]

you might start by measuring continuity from component to component.
303s get cracked traces often; their circuit boards are made of flimsy
stuff.
As for various mods go to the x0xb0x wiki or forum and you'll find plenty.

On Mon, Aug 2, 2010 at 9:51 AM, cheater cheater <cheater00 at gmail.com> wrote:
> Hi guys,
> my TB-303 has some problems and I thought I would ask around if anyone
> knows how to fix them :)
>
> 1. line output not working
> yup :( no output. There is "perfect" output from the headphones output.
>
> 2. headphone output has a faint sound of digital buzz
> When the LEDs are blinking, I can hear a buzz when the LED is on. This
> might be the way it worked out of the box - but if so I would like to
> fix it with some mods. The sound is fairly prominent and can be heard
> when the synth is playing as well, making it useless for what I want
> to do (i.e. put the 303 stems in a mix not obscured by a lot of other
> sounds. I understand you wouldn't hear that in a very busy mix)
>
> 3. power-on thump
> I assume this needs some replacement of the electrolytic caps, but not
> sure which ones exactly. I wouldn't want to just go wild on it and
> replace everything
>
> 4. decay knob doesn't do anything
> No idea why. This started recently.
>
> 5. (hopefully a mod exists for this) the filter cutoff range is too
> small. I know you can change the range around a bit with one of the
> trimpots, but that doesn't give me the needed range. I would like to
> go from around 30 Hz to 30k if possible.
>
> 6. Potentiometers are noisy and slow, i.e. difficult to drag:
> the resonance knob is especially slow! The others feel a bit wonky too
> and are probably quite worn. Is there a good replacement?
>
> 7. Waveform switch is wonky and sometimes doesn't close contact properly
> is there a direct replacement part - or do I need to open it up and
> recondition it? I would really like to avoid that :X
>
> BTW, is there a mod to change patterns in write mode?
>
> Thanks a lot,
> D.
>