restorer-john
Grand Contributor
I saw something quite interesting whilst poring over the world's first CD player, the Sony CDP-101 schematic:
CX-193. Pin 19 "strobo". And a bunch of unused (tied to Gnd) functions on the Disc Motor Servo IC. What were they for?
The CX-193 is a very early IC number from Sony and all the player ICs are in the 4 digits (CX-xxxx)
Was it actually a dedicated Quartz Lock DD turntable IC they used for the world's first CD player's BSL motor drive? Hence the unused 'strobe' output?
Yes it was! I thought of a few Sony TTs with a single point PLL derived strobes, the PSX-50 and the PSX-70 from 1978/79. These guys with the nice PUA-xx arms:
PS-X70 Turntable:
PS-X50 Turntable:
Very cool adaption of an already existing Sony Turntable IC by Sony engineers. The RAM control IC (CX-7934) controls the CX-193 to speed up or slow down the disc to ensure the RAM buffer remains optimal.
Handy to know, if you need a CX-193 for a PS-X50 or 70, as they are inside old Sony CDP-101s or vice versa.
CX-193. Pin 19 "strobo". And a bunch of unused (tied to Gnd) functions on the Disc Motor Servo IC. What were they for?
The CX-193 is a very early IC number from Sony and all the player ICs are in the 4 digits (CX-xxxx)
Was it actually a dedicated Quartz Lock DD turntable IC they used for the world's first CD player's BSL motor drive? Hence the unused 'strobe' output?
Yes it was! I thought of a few Sony TTs with a single point PLL derived strobes, the PSX-50 and the PSX-70 from 1978/79. These guys with the nice PUA-xx arms:
PS-X70 Turntable:
PS-X50 Turntable:
Very cool adaption of an already existing Sony Turntable IC by Sony engineers. The RAM control IC (CX-7934) controls the CX-193 to speed up or slow down the disc to ensure the RAM buffer remains optimal.
Handy to know, if you need a CX-193 for a PS-X50 or 70, as they are inside old Sony CDP-101s or vice versa.
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