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Yup sounds like the pitch needs to be calibrated. I've posted how to do it several times already, but hey, I'll do it once more (it just involved copy pasting a little how-to I made some time ago  )
You'll need to open up the base of your table for this. First secure all loose parts from your TT (lock the arm, remove the 45RPM adaptor and the headshell). Put the dustcover on (or top of the flightcase, anything that allows you to put the TT upside down without breaking the arm). It's best you put it upside down on a large pillow when you use the dustcover (for more stability because the pillow "absorbs" the little extrusion from the dustcover).
Once upside down, it's screwdriver time. First unscrew the four feet by hand. After that look at the black rubber base of the Technics. You should see 21 (not more) screws ordened in two circles. You'll have to unscrew them all. The only screws you shouldn't touch are those that hold the cable cache.
Once you unscrewed it all, remove the black rubber base (it can take some wiggling and pulling before it comes off). Watch out you don't rip off the cables.
You should see the bottom side of the circuit board now. Look where the pitch slider is (well the circuit board of it). There you should see a little hole (THAT's the one), it can make it easier if you unscrew the pitch slider, to improve accesibility.
Now the question is, do you have a multimeter??? If yes, it's easier. Measure the impedance/resistance of the little potentiometer (center pin - and, most outer pin +).
Factory default is 2.7 kOhm, but I've had several SL's where 3.25 kOhm gave a better result.
If you don't have a multimeter, no problem, just adjust it (be careful it's VERY precise, a slight turn is already a huge change in resistance).
Multimeter or not, it's always safe to try the setting and correct if necessary. Just temporarlily put the remaining part of the TT (no need to replace the black botton each time) normally on the pillow, and try the pitch slider. Just do it like this. Start at 0% and move to negative pitch. Watch very carefully. The dots should progressively start moving backwards (if they move forward at first, even slightly, you need to adjust more). Then do the same the other side (positive = dots should begin moving forward directly, not backwards at first...). Adjust again if necessary.
Ok if your SL wanted to cooperate (like I said before some are totally broken in that matter), you should only have one 0% left. Now wait. If you want, we'll calibrate the pitch range so it is factory default (+/-8%). Remove the platter, then the black plastic cache (4 or 5 screws holding it). You should see the TOP of the circuit board, and somewhere on it a blue potentiometer with PITCH written next to it. This is to adjust your pitch RANGE. Normally to be very precise, you'll use a frequency counter and set it to 262.08 kHz, but here it's better to do it by hand, always testing. The best way to calibrate is to set your pitch at +6%. Adjust until the +6% strobe dots stand still (the little ones, of course you need to put your platter back while testing). Once done that, set your pitch at approximatively 3.3% and the respective dots should (almost) stand still too. Same for -3.3% (I said almost, I can tell from experience that if you have a Techie that has PERFECT pitch, you're a lucky guy). Voila, calibrated.
PS : there's also another pot (older SL's : metal, newer : plastic blue) with brake written next to it. This is for adjusting the brake. Adjust it like you want (normally when set right, the platter should could to a FULL stop (this means full, not even going backwards again) in a angle from 90-120°. Test the brake several times, it should stop dead 9 times out of ten.
Once you are happy, just put everything back as it was (plastic cache, platter, pitch slider if you removed it, rubber base and all its screws, the four feet). Voila, if everything went fine, you should have a good working Technics now!!!
This is the basic calibration you should do (I wrote it for someone who had the double zero point problem, but it should suit you too).
If you don't feel confident doing this, then don't. It's a fairly easy calibration, if you're careful there is very little chance you can break something. But again if you don't feel like doing this, stay away.
I've done this on hundreds of SL's (had to check on 1200's in an electronics shop) and I can tell you on some decks it won't work (let's say 1/50 chance). If this is the case, there is probable something wrong on the potmeters or the pitchslider itself (resistance problem in most cases). Try it first and see if it solves your problem.
Normally on a perfectly calibrated
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after heated experimentation :)
