Audio Systems: Lasonic CDP-299 Boom Box, audio cassette player, diameter shaft

Question
The audio cassette player had a broken drive belt.  I replaced it and a second
belt it had with new.  Tape speed is slow, at 1.45 ips instead of 1-7/8 ips.  
Obvious slowness in sound.  Drive motor voltage is 1.4 VDC.  Is that too low,
too?  Could it be a power supply problem?  I can read schematics and do some
troubleshooting.  Thanks.  David Babbitt

Answer
Probably the belt is too tight, the friction is too high around one of the capstans or guides.  The excessive friction will drag down the speed.  If you have changed the motor it could be the wrong diameter shaft that has changed the speed.


Those are some things to look at.

Best wishes.