technics 1200 pitch correction

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Moderator
Joined 2003
Paid Member
Hi megatron and welcome. ;)

Excerpt from the Service Manual:
“When the pitch control knob is located at the center of the
position after turning on the power, the green LED indicator
is lit showing the operation condition for the predetermined
speed (either 33-1/3 or 45rpm). The pitch control is variable
in a range of about 8%.
Adjustment should be done on the basis of indicator scale.
Figures on the indicator show approximate percentages for
variable pitch control.
When the strobe dots in 4 stages marked at the peripheral
edge of the turntable appear to be stationary, variation of
individual pitches is shown.
The strobe illumination of this unit employs a
strobe-illuminator LED synchronized with the precise quartz
frequency.
For fine adjustment of the turntable speed, be sure to
effect the adjustment according to the LED illumination.
The LED illumination is not synchronized with fluorescent
lamps.”

In other words:
Remove the platter, remove the plastic cover underneath the platter and turn VR301 (only a tiny bit) which is the +/-0% adjustment of the pitch control. Mark it carefully before turning.
After every small change you’ll have to test till your satisfied with the result.

/Hugo :)
 
Moderator
Joined 2003
Paid Member
megatron said:
ok so.. in order for the pitch to be perfect i have to make sure the dots line up and are stationary?
Yes. The above description assumed you had no frequentie counter.
In case you have, things become a lot easier.
With your platter and the underlying cover removed and your pitch slider in the middle position (green LED on) connect the counter between TP27 and TP26 (ground). Now calibrate VR301 for 262.08Khz, +/-0.05Khz. This is your +/-0% pitch adjust.

/Hugo :)
 

Attachments

  • pitch1200.jpg
    pitch1200.jpg
    59.6 KB · Views: 189
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.