Thorens TD-224 Change Cycle

Change cycle:

1. Go get the record from the feed stack.

   The carrying arm moves to the left, to pick up the first record. It has a little pushing holder that fits into the hole of the top record.

2. Move the record over the turntable.

   The carrying arm picks up the record and carries it over until it is just above the turntable.

3. Check the record size by touching the record edge with the pickup arm.

   While the carrying arm holds the record still, the pickup arm moves in to touch the edge of the record with a little feeler bar. This gets the exact size of the record, for any record between 12" and 7". Since only one record is over the turntable at any one time, this means the changer can change intermixed record sizes between 12" and 7" in a random order of size.

4. Drop the record to the turntable and play it.

   The carrying arm now drops the record onto the turntable's spindle, and the arm moves in to play the record. A brush on the carrying arm cleans the record as it plays.

5. The changer trips at the end of the record, and the carrying arm moves the record to the stack of played records.

   The pickup arm lifts and swings out clear of the turntable. Then the carrying arm moves down, picks up the record, and then carries it to the left, depositing the record on the stack of already played records, which is underneath the feed stack.

6. Go get the next record from the feed stack.

   Now the carrying arm moves right, until it clears the records on the feed stack. Then it rises above the feed stack, and moves to the left to get the next record.

7. Pick up the record.

   The holder grabs the next record.

8. Move the record over the turntable. At this point, the change cycle is exactly the same as the first one.

   You can follow the continuation of this cycle in pictures 3 and 4. After the record finishes, another change cycle starts, in a manner similar to pictures 5 through 8. But this time, there is no record on the feed stack to be picked up. So the changer goes through the cycle with no record on the carrying arm.

9. At this point, the pickup arm is checking the size of the (nonexistent) record. Since the pickup arm did not find a record, it moved in close to the carrying arm. This causes the machine to shut itself off.

   After the pickup arm finds no record, it returns to the restpost. Then the carrying arm makes another trip to the played record stack, so things will be in the right position for either manual play of one record, or loading and unloading a stack of records.