Jim Leonard wrote:
wdg3rd at
comcast.net wrote:
The 6300 (and 6300 Plus) were designed and built
by Olivetti..
Their DB-25 video connector is the only reliable way ever
discovered to break a Radio Shack Daisy Wheel Printer II
I don't understand the line about the db25 monitor connector being able
to break a printer. Could you explain?
The monitor connector on the Olivetti M24 and the ATT 6300 was a
25-pin "D" connector (DB25), just like a parallel printer port.
But the monitor connector carried a low voltage DC power supply
for the proprietary monochome monitor (12V or maybe 24V). This
power supply would blow up any printer that was accidentally
plugged in to the video socket.
I saw this happen in about 1987 on an Olivetti M24 that was
fitted with the EGC (Enhanced Graphics Controller), leaving
the original 25-pin monitor socket empty. Someone plugged
a parallel printer (a Hermes colour dot-matrix) into the
monitor socket, and it didn't work any more.
--
John Honniball
coredump at gifford.co.uk