NSM Festival 160

3.5.2006:



My great Rock-Ola 451 only has room for 50 singles, so this 80 single, or 160 selection jukebox gives more freedom of choice. The NSM is also more gentle to the records than the 10 years older, but of course more good lookin Rock-Ola that will move to my gameroom for "sunday use only" while the NSM stays home.











20.5.2008:

NSM ES CPU board is from 1980, meaning the on board EPROM chips are already 28 years old. That is almost the limit of EPROM data retention, so it would be a good idea to burn new EPROMs and have the code safe for another 30 years. But, the three supply voltage 2708 chip is no longer supported by modern EPROM programmers. So I had to make a special adapter to read the chip contents. And how about writing it? No chance! The original board had one 2708 and one 2716 chip, so totally 3 kilobytes of program code. A 4k 2732 chip will be enough, and those can be handled by most programmers. It needs a little wiring though:

Between the 2732 and CPU board IC6 socket, an extra socket is needed so a few wires can be re-routed:

2732 pins 18,19,20 and 21 do not touch the IC6 socket corresponding pins. All other do.

If you can't read the 2708, download here the 2732 image.



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