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Hello.

I am modifying an 80's model Sansui direct drive linear tracking player, which is working great and is very good condition. I want to modify it to play almost vertically, purely as a fun mod project and an attractive talking piece rather than as any kind of improvement.

I think I need to find a way to increase the current going to the copper coils that drive the turntable magnet as the speed struggles to remain constant when in a-near upright position, which is understandable.

I understand that this player obviously wasn't designed to do this, but I also have a Numark direct drive deck that has no problem with wow-ing or speed fluctuation when at a near 90-degree angle (I did this as an experiment to compare the two) but it's the Sansui I want to modify, not the Numark. Being a DJ player, the Numark has more torque and I'm hoping I can make the Sansui Direct Drive similar.

Does anyone have any ideas as to how I may be able to do this? I'm not a tech but I'm ok with replacing parts on a board.

I think I do have a schematic available, or I may have a printed copy with the manual, but I wanted to ask if this would be possible before I posted any images.

Many thanks to anyone who may be able to help.

No replies yet, so why not post the circuit? Or just that part of it?

A simple modification sounds attractive, but in fact you may find that the Sansui deck is built down to a price, and that you end up changing everything, motor windings, power transistors, driver transistors, other components, power supply voltage and output current, parts within the power supply, mains transformer etc. Seems a very large and complicated project.

SonicBullet, this is not an electronics problem but an engineering one. The main bearing of your Sansui is made to work with all forces being contained on a thrust pad, usually a ball on a hardened steel surface at the bottom of the bearing. When you rotate the bearing 90 degrees the sleeves that hold the bearing vertical are taking all the thrust. It will not work, unless you want to go to the effort of making a clamp to attach to the record spindle to both hold the vinyl on the platter and take the forces from the sleeve into a caged ball race. That would work. I suggest you forget it. The parallel tracking tonearm should be OK at any angle.