Wurlitzer (and others?) in the 60s (don't know the exact year range )
also offered jukeboxes that played both regular 45s and 7-inch, 33 1/3
"small hole" discs that they advertised on the machine itself as "LP."
The speed selection occurs as the record is loaded onto the platter. The
mechanism that locks it into position in the center of the platter also
detects the size of the hole, and when it senses (senses is probably not
the right word; it implies more sophistication than this mechanism
really has) the small hole it shifts to a second drive pulley/belt.

 

Dave Morton

Atlanta 

 

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