HP-25 erratic behaviour Message #1 Posted by Alberto Fenini on 30 Nov 2009, 6:38 a.m.
ciao a tutti ! (greetings to everybody), one of my HP25 is actually behaving quite funny. When turned on, random "0"s are shown on the display, keyboard is insensitive at all and there is no way to get further than that.
It can be the first led, the last, occasionally two zero's show up,
but the unit stays like that until switched off. When switched on again the digit that turns on change position, but that's totally randomic.
It has been cleaned, the three bottom ICs have been desoldered and resoldered, and the mother board has undergone a cleaning process with vinegar and water, but no improvements ....
Has anybody ever experienced something like this ?
As always, thanks in advance for advice and help,
take Alberto
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