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Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Fri Feb 02, 2024 9:55 am
by t0nyt
Am going to change IC16 as a last throw of the QL dice
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Fri Feb 02, 2024 11:09 am
by t0nyt
t0nyt wrote: ↑Fri Feb 02, 2024 9:55 am
Am going to change IC16 as a last throw of the QL dice
Oh well, it had some effect but Minerva is still complaining about IC8
Will now break up for spares and just keep an eye on eBay for a replacement mobo
Thanks for all the advise
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Fri Feb 02, 2024 11:14 am
by Chris_68
Hi,
Sorry to hear, if you replaced the logic circuitry and the RAM that throws an error plus cleaning up the solder joints I have no further ideas.
But, if you planning to get another MB then wait to break up this one. With some luck you can by swapping components find the error and repair it.
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Fri Feb 02, 2024 11:50 am
by t0nyt
Chris_68 wrote: ↑Fri Feb 02, 2024 11:14 am
Hi,
Sorry to hear, if you replaced the logic circuitry and the RAM that throws an error plus cleaning up the solder joints I have no further ideas.
But, if you planning to get another MB then wait to break up this one. With some luck you can by swapping components find the error and repair it.
Will do. Am going to pack up all my QL stuff, until I find one, so will put it back in its case to protect it
Thanks for teaching me how to replace chips properly!
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Mon Feb 05, 2024 1:25 pm
by Popopo
t0nyt wrote: ↑Fri Feb 02, 2024 11:09 am
t0nyt wrote: ↑Fri Feb 02, 2024 9:55 am
Am going to change IC16 as a last throw of the QL dice
Oh well, it had some effect but Minerva is still complaining about IC8
Will now break up for spares and just keep an eye on eBay for a replacement mobo
Thanks for all the advise
You (perhaps) are blaming to the wrong IC.
Instead to look to RAM ICs... put an eye on multiplexers that are in charge of addressing the memory
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Mon Feb 05, 2024 1:34 pm
by t0nyt
Popopo wrote: ↑Mon Feb 05, 2024 1:25 pm
t0nyt wrote: ↑Fri Feb 02, 2024 11:09 am
t0nyt wrote: ↑Fri Feb 02, 2024 9:55 am
Am going to change IC16 as a last throw of the QL dice
Oh well, it had some effect but Minerva is still complaining about IC8
Will now break up for spares and just keep an eye on eBay for a replacement mobo
Thanks for all the advise
You (perhaps) are blaming to the wrong IC.
Instead to look to RAM ICs... put an eye on multiplexers that are in charge of addressing the memory
Thanks, but am breaking the board for spares.
Having changed logic ic’s & some memory I’ve given up and have purchased a replacement motherboard.
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Mon Feb 05, 2024 2:37 pm
by NormanDunbar
t0nyt wrote: ↑Mon Feb 05, 2024 1:34 pm
Thanks, but am breaking the board for spares.
Ok, I'm not a hardware expert -- just ask anyone here -- but if you have not solved the problem, then breaking the board for spares is going to mean, I think, that you will never be sure if the spare part is working or faulty!
Just a though.
Cheers,
Norm.
Re: Piggyback 4164 to Diagnose Memory Fault
Posted: Fri Feb 09, 2024 11:28 am
by t0nyt
Although I’ve given up on this board, I haven’t demolished it yet, but can confirm the zx8301 is good as it works on another board
Minerva still says IC8 is faulty, but can't be the IC as I've tried many and the socket all seems soldered ok with no shorts etc.