Thanks all. I had thought that DOO on the tube was a 1980s phenomenon.

Chris

In article ,
(Chris Read) wrote:

Thanks all. I had thought that DOO on the tube was a 1980s
phenomenon.

Young people today! :-)

--
Colin Rosenstiel

On Apr 1, 10:25 pm, "Chris Read" wrote:
Thanks all. I had thought that DOO on the tube was a 1980s phenomenon.

Chris

minor nitpick

Its not called DOO on the underground, its called OPO. Well at least
its called OPO all the lines I'm involved with, which at the moment
does not include the Victoria. OPO is One Person Operation and applies
today on all lines whether ATO or not.

However, the rest of the answers above stand, Victoria was ATO with
only a train operator from the start.

/minor nitpick

--
Nick

"Chris Read" wrote in message

Thanks all. I had thought that DOO on the tube was a 1980s phenomenon.

The Victoria stock uses a very simple 1960s system that's quite
different to that used in modern ATO trains. From memory, trains run at
either a standard restricted speed, or flat out, with no finer controls.

On Thu, 2 Apr 2009 10:50:26 +0100
"Recliner" wrote:


"Chris Read" wrote in message

Thanks all. I had thought that DOO on the tube was a 1980s phenomenon.

The Victoria stock uses a very simple 1960s system that's quite
different to that used in modern ATO trains. From memory, trains run at
either a standard restricted speed, or flat out, with no finer controls.

Its not quite that crude I don't think. I'm sure theres some intermediate
speeds. However despite its age IMO it provides a much more pleasent ride
than the ATO on the central line whose internal logic seems to consist of
"i'm going too fast , must slow down ... I'm going too slow , must speed up,
slow down, speed up, slow down, speed up". The hopeless software even makes
it consistently brake coming into some platforms only to speed up again
10 metres further along just to slow down again - St Pauls springs to mind.
Never mind the wasted electricity it can't do the running gear or track any
favours.

B2003

In message
"Recliner" wrote:

"Chris Read" wrote in message

Thanks all. I had thought that DOO on the tube was a 1980s phenomenon.

The Victoria stock uses a very simple 1960s system that's quite
different to that used in modern ATO trains. From memory, trains run at
either a standard restricted speed, or flat out, with no finer controls.



There were four control codes used:

420 ppm up to line speed
270 ppm up to 25mph
180 ppm coasting up to 25mph
120 ppm used in connection with signalling

for the 270 code there is a governor that regulated the speed between 21 and
23 mph. Over 25mph and the emergency brakes would come on automatically.

A seperate 15kHz signal indicated points where power could be shut off and
the train allowed to coast. As it approached the next station there were a
succession of command codes to slow the train down. Codes were calculated at
100Hz/mph so 35mph had a code of 3.5kHz. There were 3 rates of breaking
providied by mercury retarder switches down to 4mph at which pont a constant
pressure control took over to ease the braking to a smooth stop.

Very sophisticated for the time; remember, practical ICs were a decade or
more in the future.

--
Graeme Wall

This address not read, substitute trains for rail
Transport Miscellany at www.greywall.demon.co.uk/rail

"rail" wrote in message

In message
"Recliner" wrote:

"Chris Read" wrote in message

Thanks all. I had thought that DOO on the tube was a 1980s
phenomenon.

The Victoria stock uses a very simple 1960s system that's quite
different to that used in modern ATO trains. From memory, trains run
at either a standard restricted speed, or flat out, with no finer
controls.



There were four control codes used:

420 ppm up to line speed
270 ppm up to 25mph
180 ppm coasting up to 25mph
120 ppm used in connection with signalling

for the 270 code there is a governor that regulated the speed between
21 and 23 mph. Over 25mph and the emergency brakes would come on
automatically.

A seperate 15kHz signal indicated points where power could be shut
off and the train allowed to coast. As it approached the next
station there were a succession of command codes to slow the train
down. Codes were calculated at 100Hz/mph so 35mph had a code of
3.5kHz. There were 3 rates of breaking providied by mercury retarder
switches down to 4mph at which pont a constant pressure control took
over to ease the braking to a smooth stop.

Very sophisticated for the time; remember, practical ICs were a
decade or more in the future.

OK, that's a bit more sophisticated than I remembered. And, yes, I
agree that it's very impressive, and reliable, for mid 1960s technology.
Mid/late 1960s car or airliner designs would feel a lot more antiquated
compared to today's products than do those elderly 1967 stock trains.
And, unlike those trains, which remain in heavy daily use, such cars and
planes would almost all have been retired long ago.

On 2 Apr, 12:19, "Recliner" wrote:
"rail" wrote in message







In message
* * * * *"Recliner" wrote:

"Chris Read" wrote in message

Thanks all. I had thought that DOO on the tube was a 1980s
phenomenon.

The Victoria stock uses a very simple 1960s system that's quite
different to that used in modern ATO trains. From memory, trains run
at either a standard restricted speed, or flat out, with no finer
controls.

There were four control codes used:

420 ppm up to line speed
270 ppm up to 25mph
180 ppm coasting up to 25mph
120 ppm used in connection with signalling

for the 270 code there is a governor that regulated the speed between
21 and 23 mph. *Over 25mph and the emergency brakes would come on
automatically.

A seperate 15kHz signal indicated points where power could be shut
off and the train allowed to coast. *As it approached the next
station there were a succession of command codes to slow the train
down. *Codes were calculated at 100Hz/mph so 35mph had a code of
3.5kHz. *There were 3 rates of breaking providied by mercury retarder
switches down to 4mph at which pont a constant pressure control took
over to ease the braking to a smooth stop.

Very sophisticated for the time; remember, practical ICs were a
decade or more in the future.

OK, that's a bit more sophisticated than I remembered. *And, yes, I
agree that it's very impressive, and reliable, for mid 1960s technology.
Mid/late 1960s car or airliner designs would feel a lot more antiquated
compared to today's products than do those elderly 1967 stock trains.
And, unlike those trains, which remain in heavy daily use, such cars and
planes would almost all have been retired long ago.- Hide quoted text -

- Show quoted text -

We are now on the third generation "Auto driver" box as well.

Also to go to a further depth of nitpicking, it wasn't just "Shut the
Doors" and "Press two (sic) start buttons", the drivers window also
had to be fully closed (prevented beheadings at the tunnel headwalls!)

Cheers

Puffernutter

On Thu, 2 Apr 2009 04:28:52 -0700 (PDT), puffernutter
wrote:



We are now on the third generation "Auto driver" box as well.

Also to go to a further depth of nitpicking, it wasn't just "Shut the
Doors" and "Press two (sic) start buttons", the drivers window also
had to be fully closed (prevented beheadings at the tunnel headwalls!)

Unusually for the time, there were no side doors to the drivers cabs
on 1967 TS, probably for similar reasons (press the buttons, train
starts moving, try to get out for some reason and wind up half inside
and half on the platform at Seven Sisters). ISTR that when 1960TS
units were fitted with ATO they had the side doors welded shut (or
otherwise securely locked).

On Thu, 02 Apr 2009 13:03:13 +0100
Uncle Toby wrote:
Unusually for the time, there were no side doors to the drivers cabs
on 1967 TS, probably for similar reasons (press the buttons, train
starts moving, try to get out for some reason and wind up half inside
and half on the platform at Seven Sisters). ISTR that when 1960TS

Presumably they credit the current central line drivers with a bit more
self preservation instinct. Either that or the cab doors are interlocked
with the ATO.

B2003