Re: New member with early HP computers
There is a small trick to determine if the main logic is working.
Switch the system on and type BEEP and then press the EXECUTE KEY if you hear a beep most of the main logic and memory are functioning and the problem is in the display/keyboard.
Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens silverray.russia@...
Verzonden: zondag 25 augustus 2019 21:35
Onderwerp: Re: [VintHPcom] New member with early HP computers
> Does the PVAL signal from the power supply go high? If it remains low the processor will be held reset.
Sorry I didn't see Your answer on time.
Of course I have all necessary equipment for research :)
I repaired the power supply module at my woking place, and controlled all voltages in order with information in Service Manual.
The PVAL is in high state, active. Line +5V is 5.07V when has no load and 4.96V when loaded.
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