Tascam Porta 02 Mk II | 1/2 speed & Tape Stop FX | Simple voltage starve Pitch Mod using stock motor

I know a few youtubers have covered this topic already - adding a pitch control to a portastudio which no pitch control, but the tutorials are either long and seem to imply you can get an electrical shock from the inside of the Porta 02* or only show a method where the motor which came with the unit was replaced with a motor with 4 input cables.

The advantage of using a motor with a 4 pin input is you can attach two resistors in parallel, a base or calibhration trimpot and a larger pot accessible to the user oputside the unit's case. This method mimics the electrical topology of pitch controls on more expensive portastudios, and means you the user pitch control never slows the motor to a dead stop, it makes it maybe 20% slower, which is ideal for matching the pitch of the recorded material to an intrument you can't tune easily like a piano, but not so much fun for experimental sounds and textures.....

For the novice it is simpler,and requires fewer components to just wire in a potentiometer in series with the positive voltage inpiut of the supplied two pin motor, whichb is what I demonstrate in this video.

Doing this means you can easily run the tape at half or even quarter the original speed for crazy grainy textures you can't get from a standard pitch control. It also means that with the potentieometer at full resistance the entire 12 volts drops over the potentiometer and the motor stops completely, producing a "tape stop" effect you can usually only get with reel to reel players.

*Although the AC current which comes out of your wall is potentially lethal, that is converted by the Porta 02's external power supply into harmless 12v DC, so once I've tested that the PSU's output with a multimeter, I know I can tiouch the circuit while it is turned on without electricuting myself.

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