26 Feb
2020
26 Feb
'20
5:58 p.m.
Bob,
I noticed in the last photo in the 4054A EBAY auction the 4054 was on top
of a 4907 with dual eight inch floppy drives.
I checked and didn't see that 4907 being auctioned off.
Monty
On Wed, Feb 26, 2020 at 7:49 PM Monty McGraw <mmcgraw74 at gmail.com> wrote:
Bob,
I had my 4054A display stop erasing when you press PAGE key or BASIC PAGE
command.
I found the 4054 Parts and Schematics Service Manual on bitsavers.org at
http://www.bitsavers.org/pdf/tektronix/405x/4052_4054/070-2839-00_4054_Serv…
I've narrowed my issue using that manual to a 74123 one-shot multivibrator
that creates a short delay for the erase to complete. I've got a 74123 IC
ordered and should get it this week.
When I upgraded my 4054 to 4054A with an F39 option kit - the MAS board
and the IO Board were both upgraded. Those schematics aren't in the 4054
service manual.
Then I remembered my list of your documents at Living Computer Museum -
and there was an 4054A Update to the 4054 Parts and Schematics.
I've asked the Museum to scan the manual update and I'll post the scan -
so it can be saved on bitsavers.org too.
BTW - I plan to exhibit my 4054A with the 4907 floppy drive system at VCF
Pacific Northwest Festival at Living Computers Museum on March 21 and 22.
Monty
On Wed, Feb 26, 2020 at 5:38 PM Mark Linimon via cctalk <
cctalk at classiccmp.org> wrote:
On Wed, Feb 26, 2020 at 01:57:24PM -0800, Bob
Rosenbloom via cctalk wrote:
I hope I can get this one running.
Good find! Good luck!
mcl