TS1000's (ZX81's) black screen

Discussions about Sinclair ZX80 and ZX81 Hardware
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PokeMon
Posts: 2225
Joined: Sat Sep 17, 2011 6:48 pm

Re: TS1000's (ZX81's) black screen

Post by PokeMon » Sun Jan 07, 2018 4:00 pm

Here found 10 pieces for less than 1 GBP including shipment. 8-)

https://www.aliexpress.com/item/MPS2369 ... 56880.html

dessony
Posts: 196
Joined: Tue Oct 29, 2013 2:26 pm
Location: Indiana, USA

Re: TS1000's (ZX81's) black screen

Post by dessony » Wed Feb 28, 2018 5:49 am

Transistor MPS2369.jpg
Transistor MPS2369
I ordered these certain 5 transistors less than a month ago. Then, I took two NTE123A off the TS1000/ZX81 motherboard. The NTE123A's datasheet did not show any time on or time off. How sad! Anyway, I put these new two MPS2369 on the motherboard. I could read the voltage off the CPU's pin #17 and ULA's pin #16! Lastly, I put four ICs back onto the board and then hooked it up to a monitor and a power supply unit. Finally, I saw a black square with a white "K" within its area on a white screen. It worked fine now! :lol: :lol: The computer's black screen problem is finally SOLVED! :lol:

Cheers,
Dessony

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1024MAK
Posts: 2162
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: TS1000's (ZX81's) black screen

Post by 1024MAK » Thu Mar 01, 2018 2:58 pm

Well done :D

Good to hear that you have got it working 8-)

Mark

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