how decrease Technics 1200 TORQUE

[gufokiller]

Hi everybody,my name is Giulio from Napoli (italy) i have more 15.000 vinyls and i want to create aprototipe like 700 of Biz Markie. i'm working on my prototipe 7 inches technics turntable. you can see the video here:
https://www.youtube.com/watch?v=hMLkqOTLd0Q

I have to modify the electronics of the turntable. I have to reduce the engine torque. I am not an expert and I ask you about the forum.

an6675.jpg

pcb piste 1200.jpg

pcb service.jpg

I have to decrease NewtonM (torque) because rotor 7 inches dosen't have the same heavy on circonferenza rotation.
So i have just two way to fix this problem: put inside the rotor 7 inches 1.2kg more of plum (i try and works perfectly) or i decrease torque of technics because i don t have force of inertia.
thx to all pepole of this fantastic forum

[markrob]

Why do you want to decrease the torque. Is the servo unstable with the smaller platter?

[gufokiller]

Yes torque is too high and plattern doesn't have inertial force because is 7inches

[symatic]

awesome project I hope you manage to recreate these!

[boryo]

Great project and I wish you luck! I have to admit that I was a little disappointed when I saw 7" platter on top of 12" turntable Not sure if it was you or someone else but I saw a few days ago kind of the same project, 7" platter on 12" turntable, it just looked strange. Since you have small platter maybe maybe for the next revisions try to create a small body and I can assure you people will go crazy on your project Good luck!
By the way, why do you want to make it 7"? Anything to do with hip-hop?

Best,
Bob

[apoklis]

This may be helpful/or not, but this guy reverse engineer the feedback for the for a SL1200 then redoes it in a anolog form.It could be helpful if you want to go with brushless dc motor with feedback timing. Might be helpful
https://youtu.be/cOcQy9uppPM.