25 Nov
2001
25 Nov
'01
5:10 a.m.
1. Did you disconnect the screen transformer that goes
between the
video board and yoke cable? An obvious question but thought I'd ask.
Yes, I removed the transformer the goes between the video
board and yoke cable...the one taped to the side of the chasis next
to the video board.
2. Did you just swap the cpu board with screen mod ROMs
for a
standard Lisa 2 board, or have you tried putting your Lisa 2 ROMs in
the board that you know works?
I have 3 cpu boards here, two with the XL ROMs and the third
with Rev. H ROMs. I've swapped them and the video state ROM around
between the various boards. Same results regardless of which board
is used.
3. I understand that you need to tweak some of the
potentiometers on
the video board and possibly the psu. The Sun Remarketing DIY guide
to Lisa repair has a section on installing the screen mod kit, so
removal should "simply" be the reverse of that procedure... My
understanding is that the Lisa will boot with incorrect voltages but
the display will be distorted.
I adjusted the pots on the video board, but not on the PSU.
It will even boot fine with the XL screenkit ROMs but without the
additional transformer. The screen's aspect ratio is wrong and it
doesn't fill the entire screen, but it works. I've got PDF's of
Sun's stuff, as well as the two D. Craig CD's with lots of info.
4. What symptoms were displayed when you tried booting
without the
screen mod kit?
Blank screen with scan trace lines. I believe it also would
give 3 beeps as well.
Since my Profile HD is dead, it wouldn't have been much use
as a Lisa anyway but it would've been nice to get it working in it's
original configuration. There's also an internal hard disk supplied
by Sun Rem. that is mounted above the floppy and which runs off of
the external parallel port but the drive sounds and smells horrible
when powered on. Needless to say, I think it's toast! That's
ok...the 80MB drive I've not got mounted on the SCSI card should be
more than enough space to play around with it as a Mac XL. It seems
to actually be pretty usable in that configuration.
Jeff
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