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Author Archives: rjarratt
Olivetti M24 Power Supply Failure
I have had two Olivetti M24s for a while, one with monitor and keyboard but no HDD controller and one just the base unit with a HDD controller but no drives, not even the floppy disk drive. Recently I acquired … Continue reading
Olivetti M24 ANK 2462 Keyboard
When I acquired my first M24 it came with a keyboard. I had found it to be unreliable with some of the keys needing to be pressed multiple times before they were registered, and the enclosure was held together at … Continue reading
Rainbow 100A Restoration
I acquired a Rainbow 100A a while back. It had a few problems: It also came with a Floor Stand, an LA50, manuals and disks. PSU Inspection Before switching it on I checked the PSU visually, mainly for any bulging … Continue reading
VT101 on Display at Reading Museum
As part of Reading Museum’s Digital 60 event I was asked to loan my VT101. Some months ago the museum sent a driver to my house to collect it, he wrapped it up very carefully and duly took it away. … Continue reading
VT100 External Video Fixed
I have been making progress on restoring the VT100 I acquired some time ago. The RAM is now OK and the keyboard interface is working. However, I was still not getting any output on the screen and I know that … Continue reading
Posted in Retro-Computing, VT100
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VT100 Keyboard Constant Clicking Fault
In my last post VT100 RAM Fault I reported progress on fixing my VT100, getting past a RAM fault, but I left it with a fault where the keyboard constantly clicked the speaker. I knew the keyboard was OK because … Continue reading
VT100 RAM Fault
[Updated 14th October 2023] I acquired a VT100 a while back. It was just the video unit, without a keyboard, but I have a couple of keyboards for my VT101 and VT102, so I would be able to use it … Continue reading
Rainbow H7842 Finally Fixed
I previously posted about the failure of the H7842 power supply in my DEC Rainbow. I reported that after replacing some parts I was getting an overcurrent detection in the -12V output. This was under bench test conditions using a … Continue reading
DEC Rainbow H7842 Power Supply Failure
A couple of days ago, I received a request to format some RX50s in one of my Rainbow machines. So, I got this one out to check that it still works. I was happy that it just powered up fine. … Continue reading
PDP 11/24 Progress
A few years ago I was given a PDP 11/24, followed a few months later by the cabinet and two RL02 drives. Not long after, once I had first tried the PSU with a dummy load, I attempted to power … Continue reading
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