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Post by dave1 on Feb 21, 2017 13:34:51 GMT
In the goods yards on the Central & Northern lines there were a number of these signals. Anyone know why they were not all like it. These were the ones all the other goods yards did not have the yellow bar shunt.
Woodford
Buckhurst Hill
Theydon Bois
Fairlop
Ongar
High Barnet
Totteridge
Woodside Park
Finchley Central
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Post by railtechnician on Feb 22, 2017 3:51:07 GMT
Dave,
The question is wrong! It should be 'what is the purpose of a yellow shunt stick'.
Shunt signals have red bars, the repeating shunt signals (distants) had yellow bars
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Post by dave1 on Feb 22, 2017 14:34:50 GMT
Dave, The question is wrong! It should be 'what is the purpose of a yellow shunt stick'. Shunt signals have red bars, the repeating shunt signals (distants) had yellow bars RT I thought I had it right with the title. The signals I mention are shunt signals and not distants as far as I know distants had fish tails. I will see if I can get a diagram.
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Post by railtechnician on Feb 22, 2017 15:34:07 GMT
Dave, The question is wrong! It should be 'what is the purpose of a yellow shunt stick'. Shunt signals have red bars, the repeating shunt signals (distants) had yellow bars RT I thought I had it right with the title. The signals I mention are shunt signals and not distants as far as I know distants had fish tails. I will see if I can get a diagram. Fishtails or not yellow bar disc signals repeat red bar disc signals, LT practice was fishtails and BR practice was without fishtails. What you have to remember is that all the sites you mention were originally BR lines and thus signalled with BR discs. It was a long time before LT resignalling replaced most old standards. We were resignalling the Central in 1977 and taking out such things as the old BR Leyton cabin and some very large semophores, Woodford was another site that I worked on at the last knockings of resignalling there so I never saw any of the yellow shunt discs because I began my LT career as the 1970s Central line resignalling was all but done and we were clearing up the loose ends, Leyton being the biggest of those that I worked on i.e. a full changeover of signalling, other sites on the line where I worked on the full resignalling changeovers were Queensway and Holborn, Chancery Lane and St.Pauls. On the Northern in 1977/8 I only worked on the resignalling between Camden Town and Golders Green at the north end and clearing up works at Kennington, Stockwell and the three Claphams at the south end, then we moved to the Picc in 1978/9 resignalling the east end which of course the original extension and a different original signalling standard (50v supplied by the North Met Electricity Supply Co. and relays with blue frames rather than red 33.33 Hz and silver 125 Hz) to the rest of the line so Calling On and Warning disc signals at Cockfosters, Oakwood and Arnos Grove as I recall which all disappeared on the east end signalling changeovers in 1979 and 1982.
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Post by dave1 on Feb 22, 2017 15:35:48 GMT
Have done a scan so make what you want from it.
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Post by railtechnician on Feb 22, 2017 19:18:08 GMT
Have done a scan so make what you want from it. Okay, much better with a diagram! Firstly as I said I have never seen a yellow disc anywhere on LU but was always given to understand that a yellow disc was a repeater on LT lines. Indeed it was a yellow disc with a black fishtail bar mounted on a running signal post beneath the two aspect colour light and acting as a repeater (distant) for the next running signal as shown for signal NS213. Apparently used on LT open sections where BR also operated goods trains. LT practice did not include yellow discs as subsidiary signals (although it apparently adopted it and clearly there is a distinction between the two types of 'yellow disc'), this was as I stated BR practice and the 'yellow disc' was in fact a yellow bar on a black disc used in colour light areas. It was a stop signal in its own right only cleared when the route was set over a crossover from a siding or yard to a running line. It could be passed at danger when the points were set straight ahead (normal) towards a siding or headshunt such that trains could shunt freely backwards and forwards with the signal 'ON'. (LT practice allows such moves via normal shunt sticks at yard and depot outlets.) Up to five such 'yellow disc' shunt signals could be mounted on a post reading routes from top to bottom, the top disc reading to the extreme left hand route and the bottom disc reading to the extreme right most route. So 'hands up' here, my initial assertion was almost correct, I had to dig deep into my library for the definitive answer to the question.
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Post by dave1 on Feb 22, 2017 19:52:52 GMT
Have done a scan so make what you want from it. Okay, much better with a diagram! Firstly as I said I have never seen a yellow disc anywhere on LU but was always given to understand that a yellow disc was a repeater on LT lines. Indeed it was a yellow disc with a black fishtail bar mounted on a running signal post beneath the two aspect colour light and acting as a repeater (distant) for the next running signal as shown for signal NS213. Apparently used on LT open sections where BR also operated goods trains. LT practice did not include yellow discs as subsidiary signals (although it apparently adopted it and clearly there is a distinction between the two types of 'yellow disc'), this was as I stated BR practice and the 'yellow disc' was in fact a yellow bar on a black disc used in colour light areas. It was a stop signal in its own right only cleared when the route was set over a crossover from a siding or yard to a running line. It could be passed at danger when the points were set straight ahead (normal) towards a siding or headshunt such that trains could shunt freely backwards and forwards with the signal 'ON'. (LT practice allows such moves via normal shunt sticks at yard and depot outlets.) Up to five such 'yellow disc' shunt signals could be mounted on a post reading routes from top to bottom, the top disc reading to the extreme left hand route and the bottom disc reading to the extreme right most route. So 'hands up' here, my initial assertion was almost correct, I had to dig deep into my library for the definitive answer to the question. You can see a distant on that diagram with a fishtail, so I think we have cleared up that the only thing is these had a white background and not black as they would have on the main line. Now back to my original question why would some goods yards have these and others don't have them.
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Post by railtechnician on Feb 23, 2017 9:59:13 GMT
Okay, much better with a diagram! Firstly as I said I have never seen a yellow disc anywhere on LU but was always given to understand that a yellow disc was a repeater on LT lines. Indeed it was a yellow disc with a black fishtail bar mounted on a running signal post beneath the two aspect colour light and acting as a repeater (distant) for the next running signal as shown for signal NS213. Apparently used on LT open sections where BR also operated goods trains. LT practice did not include yellow discs as subsidiary signals (although it apparently adopted it and clearly there is a distinction between the two types of 'yellow disc'), this was as I stated BR practice and the 'yellow disc' was in fact a yellow bar on a black disc used in colour light areas. It was a stop signal in its own right only cleared when the route was set over a crossover from a siding or yard to a running line. It could be passed at danger when the points were set straight ahead (normal) towards a siding or headshunt such that trains could shunt freely backwards and forwards with the signal 'ON'. (LT practice allows such moves via normal shunt sticks at yard and depot outlets.) Up to five such 'yellow disc' shunt signals could be mounted on a post reading routes from top to bottom, the top disc reading to the extreme left hand route and the bottom disc reading to the extreme right most route. So 'hands up' here, my initial assertion was almost correct, I had to dig deep into my library for the definitive answer to the question. You can see a distant on that diagram with a fishtail, so I think we have cleared up that the only thing is these had a white background and not black as they would have on the main line. Now back to my original question why would some goods yards have these and others don't have them. Dave, you seem to have missed some of the points I made! Firstly I answered your original question in my second post on the topic, the sidings are signalled to BR practice standard not LT practice standard, hence the yellow disc shunt signals. This was so for those lines inherited from BR and probably not so for lines such as the Metropolitan and Metropolitan District railways which operated their own signalling systems with semaphore signalling originally. You would need historical signalling practices to know exactly what they used, I have not exhausted my signalling reference books yet but most of them are strictly BR signalling from the earliest days. I referenced NS213 as the signal with a yellow disc distant repeater, that was LT practice as I said for running lines (definitely used on the Metropiltan line) which allowed BR goods trains to deliver to Underground yards and sidings. As an LT line inherited from BR it is impossible to know whether the signalling was upgraded immediately or not, it certainly would surely have been for the running lines because the signalling overlaps etc would have been different for BR goods trains and LT electric trains but there was no necessity, I suspect, to alter the signalling immediately for the sidings and so BR practice prevailed for some time. Your diagram is unfortunately only a small section of a 'diagram' strip print so it is hard to know whether the signalling practice is simply inherited from BR or copied with necessary alterations to the running lines to incorporate LT practice of the time. The rest of the drawing including the title box and alterations notes would be a help in deciphering exactly what practice was used here and at what date(s). Here is a link to the signal box forum discussion on the LT practice yellow disc for running lines that I mention above. Here is a link to the railsigns.uk site showing the early and later type of BR practice yellow shunt disc signalI expect the later yellow on black version was the type in use on those siding roads as it had been the practice for BR new work since 1939 as far as I can gather.
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Post by Nortube on Feb 23, 2017 11:30:36 GMT
For reference for anyone following this thread, the signal diagram for the Northern Line extensions 1939/41 which shows from High Barnet to Highgate High Level / Archway is shown on Harsig's page: [ click here ]This includes the section of the diagram at Woodside Park that was posted (taken from a Yellow Peril?), although doesn't show the comments that are on the posted diagram. Going slightly away from the original topic, I see that signal NH27 at Park Junction (NB from Highgate High Level) has the two branch outer distants on it. Also, on the same post(?), is junction signal NH2 and repeater RNH 3/7. Assuming that NH2 does the same thing as NH27, what is the reason for having two different signals?
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Post by dave1 on Feb 23, 2017 11:50:19 GMT
For reference for anyone following this thread, the signal diagram for the Northern Line extensions 1939/41 which shows from High Barnet to Highgate High Level / Archway is shown on Harsig's page: [ click here ]This includes the section of the diagram at Woodside Park that was posted (taken from a Yellow Peril?), although doesn't show the comments that are on the posted diagram. Going slightly away from the original topic, I see that signal NH27 at Park Junction (NB from Highgate High Level) has the two branch outer distants on it. Also, on the same post(?), is junction signal NH2 and repeater RNH 3/7. Assuming that NH2 does the same thing as NH27, what is the reason for having two different signals? The section of diagram does come from a yellow peril (13/1940). NH2 is the junction signal with 2 routes while NH27 is a shunt for going into the depot/sidings according to the yellow peril. I have tried scanning that whole diagram from the yellow peril but the resolution was too small to read as such.
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Post by dave1 on Feb 23, 2017 11:59:58 GMT
You can see a distant on that diagram with a fishtail, so I think we have cleared up that the only thing is these had a white background and not black as they would have on the main line. Now back to my original question why would some goods yards have these and others don't have them. Dave, you seem to have missed some of the points I made! Firstly I answered your original question in my second post on the topic, the sidings are signalled to BR practice standard not LT practice standard, hence the yellow disc shunt signals. This was so for those lines inherited from BR and probably not so for lines such as the Metropolitan and Metropolitan District railways which operated their own signalling systems with semaphore signalling originally. You would need historical signalling practices to know exactly what they used, I have not exhausted my signalling reference books yet but most of them are strictly BR signalling from the earliest days. I referenced NS213 as the signal with a yellow disc distant repeater, that was LT practice as I said for running lines (definitely used on the Metropiltan line) which allowed BR goods trains to deliver to Underground yards and sidings. As an LT line inherited from BR it is impossible to know whether the signalling was upgraded immediately or not, it certainly would surely have been for the running lines because the signalling overlaps etc would have been different for BR goods trains and LT electric trains but there was no necessity, I suspect, to alter the signalling immediately for the sidings and so BR practice prevailed for some time. Your diagram is unfortunately only a small section of a 'diagram' strip print so it is hard to know whether the signalling practice is simply inherited from BR or copied with necessary alterations to the running lines to incorporate LT practice of the time. The rest of the drawing including the title box and alterations notes would be a help in deciphering exactly what practice was used here and at what date(s). Here is a link to the signal box forum discussion on the LT practice yellow disc for running lines that I mention above. Here is a link to the railsigns.uk site showing the early and later type of BR practice yellow shunt disc signalI expect the later yellow on black version was the type in use on those siding roads as it had been the practice for BR new work since 1939 as far as I can gather. RT looking at my original post I don't seem to have worded it correctly, so I will try to make it clearer for all. The list of goods yards I included were those that had the yellow bar shunt but taking the Northern line as the example East Finchley did not have such signals. They were all signalled at about the same time and to LT signalling standards, although the goods yards would be used by BR train staff only and I suspect like you have said because of the BR practice. Thinking about it I will do the diagram in sections so as to cover that section. I remember seeing such signals at Norwood Junction many years ago albeit with black background.
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Post by dave1 on Feb 23, 2017 12:08:39 GMT
I have scanned a number of sections and some text.
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Post by dave1 on Feb 23, 2017 12:09:44 GMT
They seem to want to all go together.
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Post by dave1 on Feb 23, 2017 12:11:49 GMT
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Post by dave1 on Feb 23, 2017 12:18:18 GMT
This is for Nortube taken from the yellow peril.
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