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Old 31st Jan 2021, 8:33 pm   #416
Timbucus
Octode
 
Join Date: Mar 2019
Location: Barry, Vale of Glamorgan, Wales, UK.
Posts: 1,363
Default Re: Non-working Commodore PET 3016

Quote:
Originally Posted by SiriusHardware View Post
If that were the case (very low resistance between +5V and BA10) I think Colin's resistance measurements earlier would have caught that.

It would have been quite difficult for the UB3 pin 16 signal to be what it was the first and second times it was scoped if there was a near irresistable force trying to pull that line high.
Ah yes - I said I was only paying partial attention - thanks I missed the resistance checks to +5v. Well it may just be the ability to drag them down then - ergo the buffer is weak on driving low - anyone know the LS output circuit well as to why that could happen?
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