04-06-2024, 11:40 AM
(This post was last modified: 04-06-2024, 11:53 AM by ppppenguin.)
First light!
No drama, no smoke. The 5V rail came up correctly. Quite a lot of it is working. There are hints of a circle. I hope there isn't a problem with the magnetic core memory. There are several SN7525N sense amplifiers around the core: http://marc.retronik.fr/CoreMemory/Memor...17p%5D.pdf I don't have any and it might be tricky getting hold of some if I need them.
There is some text on the screen so the text board is fitted. I haven't looked to see how the text is programmed in. The board has 6x 74150 16:1 multiplexers and a 24 pin x 0.6" ceramic cased chip that's probably a ROM. It's soldered in! Probably replaceable with a 27xx EPROM and a bit of fiddling. Correction: I've looked up the manual, the ROM contains the character set. Programming is by wire links.
Apologies for the hideous photo. The diagonal bars are camera artefacts and there are loads of reflections from the screen. This is the Y (luminance) output only. I need to hook up the RGB outputs to my bench monitor which means getting it down from its shelf and a fair bit of fiddling around. Maybe I'll look and see if I have another monitor with RGB inputs.
No drama, no smoke. The 5V rail came up correctly. Quite a lot of it is working. There are hints of a circle. I hope there isn't a problem with the magnetic core memory. There are several SN7525N sense amplifiers around the core: http://marc.retronik.fr/CoreMemory/Memor...17p%5D.pdf I don't have any and it might be tricky getting hold of some if I need them.
There is some text on the screen so the text board is fitted. I haven't looked to see how the text is programmed in. The board has 6x 74150 16:1 multiplexers and a 24 pin x 0.6" ceramic cased chip that's probably a ROM. It's soldered in! Probably replaceable with a 27xx EPROM and a bit of fiddling. Correction: I've looked up the manual, the ROM contains the character set. Programming is by wire links.
Apologies for the hideous photo. The diagonal bars are camera artefacts and there are loads of reflections from the screen. This is the Y (luminance) output only. I need to hook up the RGB outputs to my bench monitor which means getting it down from its shelf and a fair bit of fiddling around. Maybe I'll look and see if I have another monitor with RGB inputs.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
