At my whit's end with this one... Pro-Ject Classic SB Turntable repair

All,

I bought this turntable for $150, with the knowledge that it did not "turn on". It's a $2k turntable new and after research, I found the replacement parts for about $250. So, all in, I figure I'd have a roughly $2k turntable for about $400, after repair (so I thought!)

Anyway, I have now replaced all electronic parts of this turntable (Power PCB, Speed Control PCB, Motor, and new power supply 15V DC). After connecting all the new parts together, outside of the turn table casing, it still does not power on. Regardless of the turntable, these parts should at least power on, right? I am posting pics of the new parts connected and the 15v DC power supply and picture of the back of the turntable asking for DC power. Any thoughts of what else I could try with this thing?

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Do you have any service information and circuit diagrams for this because without those its going to be difficult. All you can do is check the supply voltage is reaching all the boards and circuitry. There seems to be something that looks like a crystal on one of the boards, presumable divided down to generate the AC motor drive voltages. Scope checks on that chip (look up the data sheet) would also be an initial check.

If you have swapped 'everything' then maybe there is something simple like a missing 'on' or 'run' logic level somewhere that relies on some external input.