Rare 68008 CPU in a BBC Micro: The Ultimate Vintage Computer Upgrade!

"Do We Repair This Rare 68008 CPU BBC Micro upgrade ? New Tools and Techniques!"

Description:
In this video, we dive into the repair of a rare upgraded BBC Micro featuring the 68008 CPU—the ultimate vintage computer upgrade! Using new tools in our arsenal, including a thermal camera, we troubleshoot this unique machine to see if we can bring it back to life. Will we get the upgrade working? Join us as we explore different techniques.

Timestamps

00:00 - Intro
01:03 - Lets Crack on
04:50 - Look over the board
06:33 - Lets start the repair Caps
10:04 - Battery Damage Diodes
10:41 - first problem OHNO
11:50 - Lets make a OS9 Rom
15:58 - What is OS9
18:10 - Snapped Cap Identity
18:48 - New day Problems. Can you help ?
22:24 - Predator Vision
24:57 - Outro

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#bbcmicro #bbc #cumana #retro #vintagetech

[BitRetroReFix]

That bad boy wants replicating ;) ... nice bit of kit there, buddy 😉

[ngbarnes]

I emulated this board in MAME a few years ago, so know what to expect when you get it working. I've never seen a real board running, only my emulation, and doubt anyone else has either in likely over 20 years! A surprising amount of documentation exists for this board, including schematics, which I presume you've found?
So your board didn't come with the ROM, presume you have the OS9 floppies or have you downloaded those too?

[spacebwoy]

Tantalum caps often fail short rather than open and are always worth a check.

[lloydieization]

without having a circuit diagram its hard say if 35 omhs is low, but since you are not getting 5 volts (I assume) that clearly implies something is gone (technically 35 omhs isn't a short) you should remove all the socketed chips and see if your 5 volt line returns... you tend to get low resistivity from/near power supply circuits (analog circuits)... so provided the board was disconnected from its PSU while measuring, the omh reading does seem low for a digital board, that said, there does seem to be analog circuity in lower left quadrant of this board, but your thermal imaging doesn't show much heat coming from this area... touch tests might be better than your thermals as no digital IC from this era should be so hot that can touch them for at least couple second... if you can touch for a split second that implies a bad chip.

[kwanchan]

the 68008 isn't the younger brother of the 68000 family

its more like the brain damaged sibling with learning difficulties