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QRS Computer-controlled Perforator
By Mike Walter

Hi all,  Carl Zwanzig was asking about the computer and program that
is used to operate the QRS perforators.  Back in the mid 1980s QRS
had a gentleman from the Midwest design a system whereby each paper
master being used for production was scanned and saved on a 5.25-inch
floppy disk, using a proprietary program and an Apple IIe computer.
This particular system has been used since that time and works well
to control the entire perforating process.  5.25-inch floppy disks
are still being used and there seems to still be a supply of them
"out there".

The computer reads the floppy disc row by row and sends electrical
signals to a bank of solenoids that correspond to individual notes.
When a specific solenoid receives an electrical signal, the solenoid
is activated and the armature, which has a leather pallet on top,
is pulled away from a hollow tube, allowing air to enter the system,
thereby activating a single pouch in a primary chest.  The rest of
the system is basic player piano technology.

The perforator punch head operates at approximately ten complete cycles
per second, which seems to be quite fast for a machine that was built
around 1915.

Best wishes,
Mike Walter - Former Production Manager, QRS Music Technologies


(Message sent Mon 27 Apr 2009, 13:30:04 GMT, from time zone GMT-0700.)

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