I have been using vinyl for 20 years, Technics 1210’s not Gemini so my thoughts may not be valid, however your turntable must be 100% level you can check this using the spotlights on a 1210 not sure about yours, also your tonearms must be at factory settings, if they have ever been adjusted chances are they will have lost this, the screws on the top and side of the tone arm assembly are machine tightened and are not supposed to be adjusted so if they have been chances are you will never get it quite right, You can check by removing the Cart and the counter weight and rotating your antiskate from side to side this should if all is correct move the tonearm in and out again. If this doesn’t work as I say it may not be applicable on yours but certainly gives you an indication on 1210’s that they are not quite right… In reality it doesnt really matter that much unless you are a vEry heavy handed scratch DJ, is there a particular rwason why you need them to be zeroed?
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