Technics 1200 mk2 Turntable Erratic Pitch

[Bean333]

Hi All....I'm new here, sorry if I posted in the wrong place.

One of my Technics (1200 MK2) is having an erratic pitch issue. This happens after the deck is warmed up. On zero, the table spins fine, as soon as I slide the pitch up or down, the dots go wacky and pitch is all over the place. So far I have done the following:
-changed pitch control with PCB
-changed diode 301 on main board
-changed ic301 (AN6682).
-calibrated pitch

I have read other threads on here addressing this issue, but, nothing I've seen here or researched online has helped me with this yet.

Any other suggestions would be appreciated. Cheers!

 

[Tajzmaj]

Check power supply. I think you need 20V at it's output(from my memory). You might have defective pass transistor( or some other ones). Check electrolytic capacitors especially if your unit is well used and old. Service manual is available online.

cheers

 

[Bean333]

Thank you, I will check it out.

 

[Lordlidder]

Hi All....I'm new here, sorry if I posted in the wrong place.

One of my Technics (1200 MK2) is having an erratic pitch issue. This happens after the deck is warmed up. On zero, the table spins fine, as soon as I slide the pitch up or down, the dots go wacky and pitch is all over the place. So far I have done the following:
-changed pitch control with PCB
-changed diode 301 on main board
-changed ic301 (AN6682).
-calibrated pitch

I have read other threads on here addressing this issue, but, nothing I've seen here or researched online has helped me with this yet.

Any other suggestions would be appreciated. Cheers!

Hello I've found most problems with technics turntables can be diagnosed via YouTube.... Viper frank I seem to recall. Best of luck chap