Yamaha QY 300 Owner's Manual page 37

Select the Punch-in Record Mode
For punch-in recording you must first select the punch-in mode after engaging
the record ready mode (step 4 of the realtime record process, described above).
Press the [F6] function key ("PUNCH") to select the punch-in record mode.
Specify the Punch-in & Punch-out Points
Specify the "punch-in" and "punch-out" points, the punch-in point being the
measure and beat at which recording will begin, and the punch-out point being
the measure and beat at which recording will end.
Move the cursor to the punch-in and punch-out measure and beat parameters
and set as required. Then, before actually starting recording, set the measure
parameter a few measures before the punch-in point so you'll be ready to
record when the punch-in point is reached.
Start the Punch-in Record Operation
Start the punch-in operation by pressing the
when punch-in recording is started). Recording will begin automatically at the
specified punch-in point.
Stop the Punch-in Record Operation
Recording will stop, but playback will continue, when the punch-out point is
reached. Press the key to stop playback.
In the example display above, playback will begin at the first measure,
recording will begin on the first beat of the third measure and then stop on the
fourth beat of the fifth measure.
key (there is no count-in
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