Indeed - as shown in my painting from many years ago.
But none of these clashed (ie two 94s) never met. It was 2 out of Victoria to Littlehampton and London Bridge which might have clashed.
I used to have a leaflet that the Southern Region produced for the public, listing the headcodes. It was in the same style as the timetable leaflets of the era, about 4"x3" multiple concertina folded. Will have to see if I still have it. I can't remember if it covered the whole Region, or just one Division.
This would make sense, as the 2 digit codes were made public, to help passengers catch the correct train, whereas the 4 digit train numbers were generally only used internally. Remember that this was in the days before platform indicators and such-like. Many stations had finger-boards, but there weren't always staff on duty to put them up.
Traditional Western Region train describers were made of 4 electro-mechanical stepping units, to display the 4 digits on the signaller's panel. These had ten positions, so the letter position could only display 10 letters. The Western was therefore limited to train numbers with a small sub-set of the letter codes. The Western still doggedly held onto their electro-mechanical system long after other regions had gone over to electronic systems (such as cathode ray tubes).
That's extremely limited, given that five of the letters were reserved for interregional services
Not just the WR; at the same time all Altrincham-Crewe/Alderley Edge services had headcodes which identified the route and not the train.
My understanding was - and is - that when the 4 character head code system was introduced, the standard was that for class 2/B, and some other trains, the final two characters would indicate route, and not individual train. Quite which types of train this principle applied to varied according to regional decision.
Thanks, I've learned something new! That might explain why internal Western Region codes rarely got beyond A, B and C.
Based on the info I have for the successor WR SSTD, I think that the WR electro-mechanical TDs were limited to Z A B C F E M O V and X. Note that E and F came in reverse order, both on the keyboard and in the SSTD bit allocations - I suspect that this might have been done to match the order of the letters on the stepper in the old e/m system.
I am not aware that the WR system used uniselectors. Within the signalbox area, the descriptions were stored by the displays themselves (unlike with electronic TDs, where the description is stored within the TD processor). As I recall, when a description stepped from one display to the next, a series of ten pulses was fed to the entrance display. Each stepper would step round to its home position, after which it would send the remaining pulses to the forward display and that would step. So if a counter was showing say "6", the first four pulses would put it back to its home position, then it would send the remaining 6 pulses on to the forward display to step to "6". It is possible that uniselectors might have been used for hidden storage of descriptions, for things like box to box transmissions, but I wasn't involved in the "innards". The system used standard relay sets, and all we as signal engineers did was to connect them up in predefined configurations.
As many as that?
Thanks. I come from a part of the world where passenger and freight are in different books.
No I mean year by year which was the first to appear in the timetable with an S headcode? For example the ER timetables suggest that 1S27 and 1S31 started in 1971 and 1972 respectively. Or, to put it another way, when was the first timetable when the Western actually had a train with an S code, rather than it just being a theoretical requirement?
Checking the WTTs for those which ran along the northern WCML, the first timetable issue when particular trains appeared are:-
The May 1973 timetable was the first whereby the Birmingham - Glasgow/Edinburgh sleeper was extended southwards to/from Bristol. Up until May 1973 it had started & terminated at New Street.
Looking at "the other book" (the Freight / Conditional WTTs), there were a couple of block trains which might pre-date the ones listed above.
Thanks for checking. The car trains from Morris Cowley were something I'd not considered so I went to my 1965 WR WTT for the Oxford/Banbury area and it has this:
Was the orange and grey box a WR SSTD box? Or was it a fringe to a proprietary system? SSTD was designed to repicate the old electro mechanical system in electronic form. So much so, that it had A cards, B cards, etc that carried out pretty much the same functions as the A relay set, B set etc in the old system. It was unofficially called the "Fortey describer", after the chap who developed it (Phil Fortey).
It does sound very much like a SSTD fringe unit. I seem to recall that these were also used to replace the old electro mechanical fringe units (those with the dial) when they became unserviceable. If it fringed to a Western Region panel, it would almost certainly have been in-house SSTD. If it was a fringe to another region's panel, it would almost certainly have been a contractor's proprietary unit.
Also the May 1973 timetable was when the day Paignton to Newcastle service was extended to Edinburgh. It was the year before the (faster) services on the WCML via Birmingham were to be introduced, I did wonder if it was some competitive spirit by the NE-SW team of the era. At a time when there was effectively no daytime WCML service at all in Scotland, due to the electrification works, it did well.