Sunday, March 8, 2020


If anyone is trying to use a TASCAM PORTA ONE but does not have the original PS-P1 adaptor, here is some info...

The original was:

15V DC, 400mA, center NEG, 5mm outer barrel 

The machine states 11-15V DC beside its jack, and requests that you only use the original adaptor.

I service these machines and from time to time see an original adaptor, but not often.

Many ads online claim to be PS-P1 equivalents but I have my doubts...

The funny thing is, I have tried apparently equivalent warts only to find varying degrees of 120 Hz hum in all the audio. Two 12V DC 400mA adaptors produced quite different results, both bad.

The Porta power supply PCB will regulate on board the machine, make sure you are not starving those regulators!

Unregulated DC wall warts will output a voltage at least as high as they are labeled but often much more. a cheap 9V might throw out 16V, for example. Measure yours to see what you are actually working with, rather than just trusting the label. 

I just popped out and found a used 15V DC 1200mA adaptor and that works great (no hum).

Modern switching adaptors often don't work at all. You might see the machine struggling to turn on (blinking power light) as the motor's surge current shuts down the switching adaptor over and over again.

The lesson is, get a good 15V DC adaptor with sufficient current handling ability in order to get proper performance, or use 10 C batteries haha!