Yes, I have a scope and a logic probe
Thanks
Mark.
Search found 25 matches
- Fri Mar 29, 2024 11:18 am
- Forum: Hardware
- Topic: ZX Spectrum +2a issue with all expansion cards
- Replies: 8
- Views: 3580
- Thu Mar 28, 2024 7:00 pm
- Forum: Hardware
- Topic: ZX Spectrum +2a issue with all expansion cards
- Replies: 8
- Views: 3580
Re: ZX Spectrum +2a issue with all expansion cards
Hey Mark,
Yes, I just tried a kempston joystick interface (which works on a 48K machine) and it's not working on the +2a.
I guess I'm possibly looking at a faulty ULA then?
Thanks,
Mark.
Yes, I just tried a kempston joystick interface (which works on a 48K machine) and it's not working on the +2a.
I guess I'm possibly looking at a faulty ULA then?
Thanks,
Mark.
- Thu Mar 21, 2024 3:30 pm
- Forum: Hardware
- Topic: ZX Spectrum +2a issue with all expansion cards
- Replies: 8
- Views: 3580
Re: ZX Spectrum +2a issue with all expansion cards
Which expansion cards / interfaces have you tried? Mark Hi Mark, I've tried the ByteDelight diagnostics card, 2 different V3 SmartCards from Retroleum and a Dandanator Mini - all which work fine on other Spectrum machines (including another 2a that I have). The edge connector has been cleaned, and ...
- Mon Mar 18, 2024 1:44 pm
- Forum: Hardware
- Topic: ZX Spectrum +2a issue with all expansion cards
- Replies: 8
- Views: 3580
ZX Spectrum +2a issue with all expansion cards
Hi all, Got a Spectrum +2a (black) that works just fine. It had an issue with a dead RAM chip which I replaced. My issue is that any expansion card that I plug into the back and power up results in a garbled screen once more. I thought it may have been an issue with a faulty Z80 with a bad /M1 line,...
- Mon Oct 31, 2022 6:34 pm
- Forum: Hardware
- Topic: Memotech Memopak 16 'through pcb'
- Replies: 7
- Views: 1313
- Mon Oct 31, 2022 6:32 pm
- Forum: Hardware
- Topic: Memotech Memopak 16 'through pcb'
- Replies: 7
- Views: 1313
Re: Memotech Memopak 16 'through pcb'
Thanks for confirming that, Mark.
Mark.
Mark.
- Mon Oct 31, 2022 5:46 pm
- Forum: Hardware
- Topic: Memotech Memopak 16 'through pcb'
- Replies: 7
- Views: 1313
Re: Memotech Memopak 16 'through pcb'
Hi Dessony, Your PCB's look different next to the key - each track and pad on the Memopak goes to another single pad. You have 2 pads connected together on your PCB (looks like GND?) - are you sure this would work with the memopak16? EDIT: I've attached pics of the front and back of the Memopak conn...
- Thu Oct 27, 2022 3:52 pm
- Forum: Hardware
- Topic: Memotech Memopak 16 'through pcb'
- Replies: 7
- Views: 1313
Memotech Memopak 16 'through pcb'
Hi all, Does anyone know if someone has recreated the little through PCB on the Memotech Memopak 16? The little PCB that's soldered onto the ZX81 connector that allows another peripheral to be connected to the back of the RAM pack? I have one that I picked up that has a broken connector - and someon...
Re: ZX Fail
IC25/26 being faulty will certainly cause you issues with upper RAM..
I would socket them both and replace them. Probably find that will sort the issue.
KbJ
I would socket them both and replace them. Probably find that will sort the issue.
KbJ
- Sat Nov 13, 2021 3:02 pm
- Forum: Hardware
- Topic: ZX Spectrum 128k toastrack horizontal bars at power up
- Replies: 21
- Views: 10930
Re: ZX Spectrum 128k toastrack horizontal bars at power up
Hi 1024MAK
It's a plastic OTP ROM (Intel P27256) I think? (Could be a mask ROM I guess).
I've attached a pic.
Cheers again,
KbJ
It's a plastic OTP ROM (Intel P27256) I think? (Could be a mask ROM I guess).
I've attached a pic.
Cheers again,
KbJ