On July 16, Rich Beaudry wrote:
I recently acquired an Osborne One, but it seems to be
having a video
problem -- as in no video at all. I did the obvious - played with the
brightness and contrast -- but still nothing. If I press a key on the
keyboard, the floppy starts seeking, so I assume the rest of the computer is
at least partially working, but I get no video output at all. I have NO
docs or schematics, so it's a bit hard for me to test stuff out. The CRT
make no noise at all when power is either turned off or on (no static or
hum, or anything else). Also, I took the cover off, and carefully looked
inside while turning the power on, and the CRT didn't light up, or have any
other response.
No light from the CRT's filament? That's a bad sign. If there's
enough room in there, it might be a good idea to look carefully at the
neck of the CRT and try to identify the filament pins, then check
between them with an ohmmeter to see if the filament is open.
I have an operational Osborne One here, with the manual...if you want
me to look anything up for you, or do any probing, let me know.
-Dave McGuire