NorthStar Horizon Restoration - Part 2

This is one of my favourite computers. I own four of them in various states of repair. So I decided to do a rebuild to make a really nice one that works. This page will be updated until the project is working. Last change was

17th January 2018 Thanks for the memory

I cleaned up the working memory card and it thanked me by ceasing to go however, found another machine with a HRAM6. On some of the others C8 has exploded on initial power up, so the question is to replace it -or- risk it blowing and possibly damaging the last board I have. I saw it was rated at 35v so decided to try it. It went bang and caught fire. However replacing it the board works 100% and passes the memory test. So I now have a working machine.

20th January 2018 Replacing an incapacitor

After a bit of poking around on a duff HRAM board, I determined there was a short on the +12v rail.

This turned out to be C3 which is on the output of the regulator. The capacitor on the input blew when the card was powered up, but the regulator limits the current on the output side. After replacing the capacitor the board passes a memory test and a second board had the same fault and is now 100% too.