I know there have been a few questions on this in the past but a Plus/4 novice would like some help in diagnosing a fault.
I obtained a mint condition Plus/4 (“untested”) a few weeks ago which outputted a black screen to TV when turned on (power LED comes on). I have since purchased a second Plus/4 in poor condition to act as a donor machine but this also has the same symptoms.
I’ve checked old threads and the suggestions seem to be to replace the chips en masse until a combination is found that works, however I’m not sure this is a good idea given that both machines have the same symptoms. I could start to buy replacement chips but I would start to incur serious expense to fix a cheap purchase.
Is there anything I can do to try and narrow down the potential fault? I’ve looked at the Diag 264 but I assume that this would no be recommended due to the lack of screen output. Is that correct?
Any help would be gratefully received!
I obtained a mint condition Plus/4 (“untested”) a few weeks ago which outputted a black screen to TV when turned on (power LED comes on). I have since purchased a second Plus/4 in poor condition to act as a donor machine but this also has the same symptoms.
I’ve checked old threads and the suggestions seem to be to replace the chips en masse until a combination is found that works, however I’m not sure this is a good idea given that both machines have the same symptoms. I could start to buy replacement chips but I would start to incur serious expense to fix a cheap purchase.
Is there anything I can do to try and narrow down the potential fault? I’ve looked at the Diag 264 but I assume that this would no be recommended due to the lack of screen output. Is that correct?
Any help would be gratefully received!