Ttpilot
Experienced Member
About a year ago I fired up my ancient North Star Horizon. It had sat since about 1986. Lo and behold it worked...for a couple of weeks, after which it would no longer boot. I finally got myself a multimeter and started checking voltages on the motherboard (it's been 40 years since I've done this sort of thing, so I'm pretty rusty). The voltages from the power supply to the motherboard were all good. The voltages powering the floppy disks were also good. I got about +10v on bus pins 1 and 51, +20v on bus pin 2, and 0v on bus pin 52. Looking at the motherboard power supply schematic, I'm guessing one of the tantalum capacitors (C1 perhaps?) has failed. I've included the schematic. I'm looking for advice from folks who are more experienced than I am, and I'm guessing that's most of you
Thanks in advance
Thanks in advance
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