This turntable was part of an integrated system: I only have the turntable and am trying to figure out how to make it work standalone.
There is an 8-pin DIN plug on the back that once connected the turntable to the main unit. This plug is marked "TO CACEIVER" J106 on the following sch ematic for the turntable:
The same plug is marked "PL CONT" on the schematic for the main unit:
Working from the schematics, I saw that the turntable uses a -12 0 +12 powe r supply, which I've duly connected to pins 1-6-4 on the plug (29,28,27 on the turntable schematic). Sure enough, the unit powers up, the track indica tor 7seg LED lights up, and I can operate the tray using the "Open" button on it, the fwd/rev buttons that move the cartridge left/right, and the vari ous programming buttons on the tray (track select, program, etc.)
However, the turntable never spins, the "Start" button has no effect. I thi nk this is because I am not providing the correct signals on the pins marke d "SYNC", "AF" and "STP" (shown on the main unit schematic).
Two of these three pins (24 & 25) are connected to IC151, a BA612 quad driv er, on the turntable circuit board: 24 seems to be an input signal to the t urntable (since it goes to a BA612 driver input, pin 2). The other, 25, loo ks like an output signal from the turntable to the main unit. Finally, pin
26 also looks like an output, some sort of current source from Q221?I'm at the limit of my expertise with this - can anyone suggest how to conn ect pins 24,25,26? Any ideas about what "SYNC", "AF", and "STP" might mean in this context?
Thanks!