18 Aug
2008
18 Aug
'08
1:47 a.m.
On Sun, Aug 17, 2008 at 02:00:02AM -0400, der Mouse wrote:
I'm moderately sure that the paper tape I used back when I had a PDP-8
was not symmetric in the way needed here - the line of feed/timing
holes was not on the centreline of the tape.
You are remembering correctly - they are not.
*But*, you could read the tape one way, flip it _and_ read it backwards.
Syncing up the two passes is just an exercise for the student ;-)
Personally, my PC04 is the primary load device for one of my PDP-8/Ls.
I'd be hurting if I lost a phototransistor - the SMT idea sounds handy.
What I'm more worried about is a spare bulb - It's a "festoon" bulb
(the kind commonly used for older automobile dome lights - it looks
like a large AGC-type glass fuse, with an axial filament), but trying
to cross it with a modern one from Osram or others has drawn a blank
for me. Has anyone found a modern substitute?
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 18-Aug-2008 at 08:40 Z
South Pole Station
PSC 468 Box 400 Temp -81.8 F (-63.2 C) Windchill -126.1 F (-87.8 C)
APO AP 96598 Wind 14.6 kts Grid 31 Barometer 668.9 mb (11050 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html
Speaking of the PC-04 Paper Tape Reader/Punch, I have
one for my PDP
8/e system, but one of the ten phototransistors in the monolithic
array is shorted, making it pretty useless for reading tapes.
Read the tape, flip
it upside down, read it again, flip the bits,
merge.