Punched card signalling

[Rup]

Is it true that some signalling on the Underground still uses punched cards?

 

[swt_passenger]

Is it true that some signalling on the Underground still uses punched cards?

Yes, some of the more ancient signalling uses what are called programme machines, in the interlocking machine rooms (IMRs). They are more like a punched roll, (nowadays made of plastic), rather than a sequence of cards, I think that in principle the entire day's normal sequence of events is on the rolls.

There's a description here last updated in 2013:

http://www.squarewheels.org.uk/rly/programme-machine/

 

[Dstock7080]

Few if any locations survive with programme machine rolls, they have been crudely converted to have a PC/laptop interface input, the rolls being dispensed with.

 

[Daniel]

Ta da!

EDIT - no idea why the photo has uploaded upside down!

 

[Domh245]

Ta da!

EDIT - no idea why the photo has uploaded upside down!

And for my next trick, I will transport Golder's Green to Australia!

 

[Rup]

Thanks, guys. Very interesting.

 

[kentuckytony]

Just FYI - and a bit off topic - back in the '70s we used Mylar punched tapes to run out NCR lathes in the machine shop - paper ones until we got the bugs worked out while programming!

 

[AndrewE]

Another snippet: a computer-literate colleague familiar with programming and playing with main-frame computers in the mid-70s (and there weren't many like him around then) was recruited by LT to write the computer programs that took the WTT and punched the program rolls.
In those days I think only a few universities had their own computers, each usually in its own dedicated building!
--- old post above --- --- new post below ---

And for my next trick, I will transport Golder's Green to Australia!

Are you sure that one's not at the bottom of the Goodge St lift shaft?

 

[ac6000cw]

Another snippet: a computer-literate colleague familiar with programming and playing with main-frame computers in the mid-70s (and there weren't many like him around then) was recruited by LT to write the computer programs that took the WTT and punched the program rolls.
In those days I think only a few universities had their own computers, each usually in its own dedicated building!

By the mid-70s I think most British universities had their own 'mainframe', usually from IBM or ICL. The smallish one I attended had an ICL 1900 series mainframe - programs were submitted on stacks of punched cards. It also had a DEC PDP-11 minicomputer - on which you saved your programs to punched paper tape, after you had typed them in on a Teletype terminal... (Both systems did also have magnetic disk and tape storage, but usually mere undergraduates didn't get access to that - it was reserved for more serious work).

 

[Daniel]

This may also be of interest - we still use (computerised versions) of program machines -

 

[AndrewE]

This may be of interest too - direct from the horse's mouth, or keyboard:

I used to know a fair amount about programme machines back in the
1970s as I worked with a suite of computer programs which processed
Underground working timetables, originally just to produce paper tape
which was then read by a machine in the Signal Engineer's Department
to punch the programme machine rolls. There were further local
oddities like shunt paths, which were inserted on the roll where
there was a gap in the service and allowed someone on a local panel
to set up shunt moves (at places like Parson's Green where they had
to use the running lines) without confusing the programme machines.

IIRC the first location where a computer was used instead of a
programme machine was Heathrow Central and the timetable was loaded
from paper tape. However, it was made to look like three programme
machines to the staff in the control room.