Recent content by Elemenoh

@jktw which board(s) do you need to recap?

I got the original PrairieTek 20MB hard drive imaged. Here's the recipe I used. Beige G3 desktop Mac with a USB card installed USB hard drive USB thumb drive Burned a CD with Debian linux 8 (debian-8.11.0-powerpc-CD-1.iso) Put gddrescue_1.19-1_powerpc.deb on the thumb drive Installed Boot X on...

Repair update: I did get the old drive working after replacing the blown opamp. It has Outbound software version 1.3b2, which I think is already available online, but I'm going to attempt to image the drive regardless. As I was working with the machine, I noticed side-to-side tracking was...

I connected the HDD's 12V/5V rails to a bench power supply and it still wouldn't spin up and was dragging down the 5V rail. Checked its main board with a thermal camera and found that a L272D at U15 was getting hot. That's an opamp that likely drives the motor. While I wait for a replacement IC...

Almost 100 capacitors later and this machine is working again. I need to adjust the CRT a bit, but otherwise she's working well!

Here's what the HDD sounds like at boot. A ~1sec attempt to spin while the boot chime is happening.

It turns out this bodged in resistor near one of the legs of the HDD bracket was shorting against it. I added some kapton tape to it and the machine turned on! 🎉 Unfortunately the HDD is now not fully spinning up. It tries for maybe a second before giving up. Tried a bunch of cycles but it...

Do you know what itd be listed as other than a flat flex?

Thanks. That makes sense intuitively. It was a bear to get out and might have gotten damaged. I’ll beep it out.

Still just getting horizontal lines on the screen. They're usually regularly spaced and thin, but occasionally chunky and random. Things I tried doing that didn't change the symptom: - Separated back panel from system - Removed ROM - Cleaned ROM and RAM incl. sockets with contact cleaner -...

While I was at it I measured the caps pulled from all of the other boards. So many! Power Supply RatedMeasured% DevDFNote 0.47µF 100V506nF+7.7%0.02In spec 10µF 63V9.4µF-6.0%0.04In spec 9.6µF-4.0%0.04In spec 10µF 250V10.9µF+9.0%0.02In spec 10.8µF+8.0%0.02In spec 47µF 25V44µF-6.4%0.09In spec...

I finished recapping the analog board on the MegaPixel display. Though it seemed to be working fine, many of the caps were out of spec or outright bad. RatedMeasured% DevDFNote 0.47µF 100V447nF-4.9%0.08In spec 1µF 100V778nF-22.2%0.18Out of tolerance 1µF 160V930nF-7.0%0.20Borderline DF 22µF...

Slightly better shots of top and bottom side.

@Kai Robinson I'll try to get better photos the next time I tear it down, but here's what I have.

@trag I found one new on eBay for a decent price so got that. Thanks for the model ID!