Need schematic

I have a linn pre tek pre amp and the left channel  recently went  and the right Chanel  is clipping the amp. I am using by back up pre amp a nad 1000 ELNA but the sound is lacking dose anyone  know where I can get the schematic  for the linn pre tek I have a shop that can fix it if I can find a schematic  they have had no luck thank you Mal11963