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Timbucus · 2nd May 2020, 2:02 pm

I have compiled quite a dossier on this device and have been slowly assembling a history of it - there are quite a few surprises on it which I I hope to put into a coherent document which I will obviously share.

I have also pretty much completed a reverse engineer of the SCRUMPI 1 - these are my notes so far SCRUMPI1BuildNotes.txt

Feelers put out to known owners of them have not resulted in replies as I had hoped to get better scans of the actual PCB for an authentic layout. So for the moment I am just sticking with building on a vero board - my illness happened just as I was getting started so has been on a backburner for a while.

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On the rebuild front due to lack of time I have only managed to make the clock circuit work (on the breadboard in the above photo) to prove my guesses on the resistor values gained from study of the one or two photos online including the one in the above PDF.

Hopefully if others are interested we can work towards a real PCB - I do feel that adapting it to use the later +5v only NMOS version of the Chip is worthwhile before attempting to tackle the slightly more complex II or III for which at the moment the PROM images are missing.

2nd May 2020, 2:02 pm	#8
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,364	Re: Good review of SC/MP. I have compiled quite a dossier on this device and have been slowly assembling a history of it - there are quite a few surprises on it which I I hope to put into a coherent document which I will obviously share. I have also pretty much completed a reverse engineer of the SCRUMPI 1 - these are my notes so far SCRUMPI1BuildNotes.txt Feelers put out to known owners of them have not resulted in replies as I had hoped to get better scans of the actual PCB for an authentic layout. So for the moment I am just sticking with building on a vero board - my illness happened just as I was getting started so has been on a backburner for a while. On the rebuild front due to lack of time I have only managed to make the clock circuit work (on the breadboard in the above photo) to prove my guesses on the resistor values gained from study of the one or two photos online including the one in the above PDF. Hopefully if others are interested we can work towards a real PCB - I do feel that adapting it to use the later +5v only NMOS version of the Chip is worthwhile before attempting to tackle the slightly more complex II or III for which at the moment the PROM images are missing.