You don't change the speed of the motor. You have to use a smaller rubber pinch roller on the capstan drive.

http://en.wikipedia.org/wiki/Tape_transport

http://www.terrysrubberrollers.com/

Don't you mean larger?

Jim

One thing you want to watch out for/checkout, is whether the cassette drive can handle that frequency response. If it is a good quality deck, then the read head and electronics will probably handle it.

What happens if you put twice the voltage to the motor only.? ie a battery direct to the terminals of the motor, and a switch on the outside?

maybe try it on a junk machine from a charity shop first, or ask for one on freecycle. I remember taking loads apart and the motors worked on any battery, but I don't remember if they went faster with more voltage,

Cnc jim

The size (diameter) of the capstan drive controls the tape speed, not the rubber pinch roller, which is just an idler. The capstan itself is coupled to the motor.

Might be easier to just buy a used 2 or 4 track recorder with variable speed control. A Tascam 424 comes to mind and can be had for +/_ 50 Bucks.

Thanks for that, I think a pwm controller connected to the motor powered externally is the best option. I have a few pwm controllers from old drills in my shed.

Your motor will be dc won't it, after the power supply, will the pwm work with that?

Also, is your 'thanks for that' directed at 5 not 6?

cnc jim

Not so! The pinch roller being rubber is driven by the motor shaft. It's the friction of the rubber that transports the tape, not the motor shaft. Increasing the diameter of the motor shaft would also work, but a tape casette can only accomodate a certain size shaft.

I have found that cassette tape motors in the cheaper sets are controlled internally by centrifugal circuit breakers. When the speed is too high, it switches off. The only option would be to replace the motor.

I have fixed it! I crammed a piece of tin foil into the hole on the back of the motor and now it runs at full speed. It has almost CD quality sound now. They all should have been made that way to start with. Of course, I had to re record all the music and data tapes I have.

I remember when I was a teenager I wanted to put all my music from cassettes over to a reel to reel tape recorder so I could have many hrs of music non stop & on my machine there was 2 ways of changing the speed. There was a switch to do it electronically & for mechanical speed change there was a small sleeve that you could slide over the capstan drive pin it had a small key on the end to drive without any slip. Running the recorder without the sleeve made it very slow & allowed up to 8 hrs of play on 1 tape for recording speeches, classes & any thing not requiring high quality. So increasing the capstan drive pin size speeds up the tape speed & the rubber roller is a free spinning wheel that is driven by the capstan pin. To me increasing the size of the capstan drive pin would be the easiest way to increase the speed of the tape. This way you would not be interfering with the electronic speed control that keeps the tape at a constant speed. I think constant speed would be critical to being able to reread the data on the tape.

never but 1-ce used the audio cassette tape drive to ?? commodore interface (too long ago (age 6 Yo! )) anyway

if you increase the tape speed the dt for flux to be stored per dL of the tape reduces it's likely (trivia) you should also rise the peak pulse voltage and narrow the peak at the same time (incase of the digital data) ...

^{don't know about this - no time to play with everything}

I don't understand what you mean.

you crank up the voltages to the motor...