Pioneer PL-400 motor spins back and forth like a washing machine Help

[Ric Harris]

Picked up and old PL-400 direct drive at the goodwill. Plugged it in and the platter agitates like a washing machine. That's one I've never seen. Any guess as to a remedy.

 

[Ric Harris]

Picked up and old PL-400 direct drive at the goodwill. Plugged it in and the platter agitates like a washing machine. That's one I've never seen. Any guess as to a remedy.

It's kind of comical to watch.

 

[boreas]

That's what happens when the platter is removed.

John

 

[pustelniakr]

Picked up and old PL-400 direct drive at the goodwill. Plugged it in and the platter agitates like a washing machine. That's one I've never seen. Any guess as to a remedy.

What you described is generally caused by a missing F clock (TP4 on the motor drive board, comes from IC1 (PD1003), pin 15). If so, sorry, parts unit time. They don't make that chip anymore.

You will need some tech knowledge, an oscilloscope, and a service manual.

Enjoy,
Rich P

 

[Ric Harris]

That's what happens when the platter is removed.

John

LOL! You are correct! Thanks!

 

[Ric Harris]

What you described is generally caused by a missing F clock (TP4 on the motor drive board, comes from IC1 (PD1003), pin 15). If so, sorry, parts unit time. They don't make that chip anymore.

You will need some tech knowledge, an oscilloscope, and a service manual.

Enjoy,
Rich P

Fortunately putting the platter back on worked. I have a donor however. It's dead as a doornail.

 

[pustelniakr]

Fortunately putting the platter back on worked. I have a donor however. It's dead as a doornail.

Yes, the motor will rock back and forth without the platter installed, but the original description of the problem stated that the "platter" rocked back and forth. Hence, my confusion.

Glad you got her working.

Enjoy,
Rich P