Re: Optical scanner for Music Box Discs
By Robbie Rhodes
Horst Mohr and a few others in our Digest group have built music roll readers using discrete photodetectors which replace the hoses and pneumatic sensors in a "tracker bar" reader. The "Optical Scanner" machine is a video system with no tracker bar. Wayne Stahnke has demonstrated that both methods are capable of recovering all of the critical detail and timing from a music roll, with sufficient precision that a "hole for hole" duplicate can be perforated. The primary advantage of the optical scanner "camera" is that it can easily be adjusted to scan any format of music roll, in any size.
If you wish to build a reader for music box disks you should contact our member Ron Yost, who built a reader using fiber-optic strands to couple the separate photo-detector array to the light at the holes of the tracker-bar. This method would accomodate the close channel spacing of the music box disk. I've seen photodiodes of 0.080-inch diameter, but I don't know if smaller devices are readily available.
I once saw a 36-inch music box disk; it seemed gigantic! How many channels does it have? Some styles of disks have a metallic projection on the rear side. Won't this create a problem in an optical reader?
{Jody, can you provide the current address for Ron Yost?}
[ I'll let Ron do that. Jody
Best regards,
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| Robbie Rhodes |
| Return-Path: rrhodes@foxtail.com |
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(Message sent Sun 4 Aug 1996, 21:27:29 GMT, from time zone GMT-0700.) |
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