I've recently come by a ZX81 from a friend of a relative who sadly died. I've been cleaning it up, but haven't dared switch it on yet! I have learned a lot from you, but have nowhere near your level of expertise, so I hope it just works.
Excellent video and work. For heat issues, I use my compressed air can and hold it upside down. Cold air comes out, and I spray IC in question. Works the same as you adding heat. Thanks for sharing another great video
Great tip, I've always bent the leg out. Sometimes accidentally breaking legs off. You may want to get a Z80 tester kit. Fun little soldering project and they work great.
Your "bad z80" might not be bad at all.. i noticed it's a modern one, and those are CMOS whereas the originals are NMOS. My guess would be the CMOS one is unhappy in this system as there are slight differences in levels and driving strengths
Love that pin isolating trick. Definitely stealing that! 😂
Great video 😁
Handy when trying to find which ram chip is shorting out a voltage supply
I've recently come by a ZX81 from a friend of a relative who sadly died. I've been cleaning it up, but haven't dared switch it on yet! I have learned a lot from you, but have nowhere near your level of expertise, so I hope it just works.
Are you able to check the polarity and output voltage of the PSU before plugging it in?
Excellent video and work. For heat issues, I use my compressed air can and hold it upside down. Cold air comes out, and I spray IC in question. Works the same as you adding heat. Thanks for sharing another great video
Thanks Rudy!
Great tip, I've always bent the leg out. Sometimes accidentally breaking legs off. You may want to get a Z80 tester kit. Fun little soldering project and they work great.
I shall have a look!
Great video :)
Waiting for the next Jet Set Willy playthrough though.... ;)
Next evening I have free from bench work!
Great vid. I’ve re-subscribed.
What doesn't fit in a ZX81 is a socketed ULA with a heatsink. Ask me how I know. D'oh!
Oh no!
👌🏼
Your "bad z80" might not be bad at all.. i noticed it's a modern one, and those are CMOS whereas the originals are NMOS. My guess would be the CMOS one is unhappy in this system as there are slight differences in levels and driving strengths
Interesting! Thanks. I'll see if I can find it and test it, I can't remember if I put it in the IC graveyard