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IMRs
Aug 17, 2013 9:45:25 GMT
Post by hellocontrol on Aug 17, 2013 9:45:25 GMT
While having a few drinks a discussion took place was there such a thing as a standard IMR, some in the group said yes depending which line you were talking about but I don't think there is/was a standard IMR they all seem to have something different.
I will ask here and see what people on here think as I am sure that the discussion will continue at the next drink up.
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IMRs
Aug 17, 2013 13:00:22 GMT
Post by railtechnician on Aug 17, 2013 13:00:22 GMT
While having a few drinks a discussion took place was there such a thing as a standard IMR, some in the group said yes depending which line you were talking about but I don't think there is/was a standard IMR they all seem to have something different. I will ask here and see what people on here think as I am sure that the discussion will continue at the next drink up. Standard in what way?
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IMRs
Aug 17, 2013 14:08:16 GMT
Post by hellocontrol on Aug 17, 2013 14:08:16 GMT
While having a few drinks a discussion took place was there such a thing as a standard IMR, some in the group said yes depending which line you were talking about but I don't think there is/was a standard IMR they all seem to have something different. I will ask here and see what people on here think as I am sure that the discussion will continue at the next drink up. Standard in what way? That's the question like I said up thread I don't think so but during the conversation some of those believed that there must be a standard IMR. You have your V frame and relays etc but I suppose there must have been some sort of basic style or design but it must depend on which line you are talking about.
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IMRs
Aug 17, 2013 16:01:57 GMT
Post by railtechnician on Aug 17, 2013 16:01:57 GMT
That's the question like I said up thread I don't think so but during the conversation some of those believed that there must be a standard IMR. You have your V frame and relays etc but I suppose there must have been some sort of basic style or design but it must depend on which line you are talking about. Not all IMRs with frames have V style frames, Ealing Broadway is an example! V Frames might be anything from one section to 6 sections of 12 levers. The modern trend is not to have lever frames at all so there are no IMRs on the Central. I expect the Jubilee is the same now with TBTC, the Northern will soon be if not already and the other lines will follow. IMRs have a safety side and a non-safety side, according to when an IMR was built different safety and non-safety standards will have been applied thus the non-safety side may be relay, electronically or computer controlled. The non-safety control medium between signal operator desk and interlocking machine non-safety side may be slow speed scanning, high speed scanning, S2 scanning, X25 network etc.
Some IMRs were directly controlled and others indirectly controlled e.g. Ealing Common and Acton West driven off Acton East.
The programme machines came in different voltages and frequencies to suit the standard of the power supplies.
Power supplies are different, the old standard was 33.33Hz 600v signal main and the later standard was 125Hz 600v signal main, both are extant. Locally derived supplies depended upon the standard in force, relay, electronic, computer, hybrid etc.
Safety circuit designs for signal selection, track circuiting, point control, have evolved into several designs through the years and so the way that racks associated with those circuits are laid out has altered.
Newer IMRs were fitted predominantly with Q relays rather than Westinghouse cubic foot fishbowl relays, there are different generations of Q relays, the Victoria line type and the later BR930 type used on the Bakerloo resignalling of the 1980s and elsewhere for mods.
Train describer equipment is another area where there are many differences to be noted, the District used the drum store, the Picc used ribbon storage for example, these being replaced by electronic TD stores which were also used for new work. Combinators were either purpose designed units or circuits were built from discrete PO type relays. Wiring was also different, 1/052 was the safety circuit standard at one time and the colour was a rough guide to the age of the room i.e. dark green was 1950s or older, light grey was 1950s/1960s, light green or orange was 1970s. The 1970s also saw a different standard where green 1/044 was used, in the 1980s it was STC red or black double insulated single core closely followed by brown single on the Bakerloo resignalling and later still black or blue single core Raychem. The colours of wires in safety signal circuits have no meaning whatsoever! Other colours found in IMRs are yellow, roberta blue and green in 7/036 any of which can be earth or live, in the old days all the busbars were fed with green 19/036 singles, regardless of designation. Obviously metric replaced the old imperial standard in the later IMRs. Mechanically equipment racks and fuse bays also evolved from grey or green painted steel to unpainted aluminium and shapes changed to suit new standard layouts. In the newer IMRs circuits were fitted with miniature circuit breakers instead of fuses. The bottom line is that no two IMRs were/are identical even if the track layout was identical. Every IMR was unique, most in more ways than might be imagined. We had a saying on signals, if one of anything exists it is a standard! In general terms there were similarities between sites on a particular line, most Central line IMRs had the same sort of atmosphere, usually dim rooms with cream painted walls, District IMRs and Northern IMRs tended to smell of cooked Marley floor tiles which were stuck to the walls and ceilings while the Vic line IMRs were notable for being fully lined in aluminium sheet and wired predominantly in asbestos braided incoming cables. The one similarity with all IMRs was the floor tiles lovingly cared for by signal lineman who kept them polished with red cardinal. I can't recall ever being in an IMR that didn't have a red tiled floor. I'm sure I have missed loads of differences, it's nine years since I last saw the inside of an IMR.
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IMRs
Aug 18, 2013 12:55:22 GMT
Post by hellocontrol on Aug 18, 2013 12:55:22 GMT
That's the question like I said up thread I don't think so but during the conversation some of those believed that there must be a standard IMR. You have your V frame and relays etc but I suppose there must have been some sort of basic style or design but it must depend on which line you are talking about. Not all IMRs with frames have V style frames, Ealing Broadway is an example! V Frames might be anything from one section to 6 sections of 12 levers. The modern trend is not to have lever frames at all so there are no IMRs on the Central. I expect the Jubilee is the same now with TBTC, the Northern will soon be if not already and the other lines will follow. IMRs have a safety side and a non-safety side, according to when an IMR was built different safety and non-safety standards will have been applied thus the non-safety side may be relay, electronically or computer controlled. The non-safety control medium between signal operator desk and interlocking machine non-safety side may be slow speed scanning, high speed scanning, S2 scanning, X25 network etc.
Some IMRs were directly controlled and others indirectly controlled e.g. Ealing Common and Acton West driven off Acton East.
The programme machines came in different voltages and frequencies to suit the standard of the power supplies.
Power supplies are different, the old standard was 33.33Hz 600v signal main and the later standard was 125Hz 600v signal main, both are extant. Locally derived supplies depended upon the standard in force, relay, electronic, computer, hybrid etc.
Safety circuit designs for signal selection, track circuiting, point control, have evolved into several designs through the years and so the way that racks associated with those circuits are laid out has altered.
Newer IMRs were fitted predominantly with Q relays rather than Westinghouse cubic foot fishbowl relays, there are different generations of Q relays, the Victoria line type and the later BR930 type used on the Bakerloo resignalling of the 1980s and elsewhere for mods.
Train describer equipment is another area where there are many differences to be noted, the District used the drum store, the Picc used ribbon storage for example, these being replaced by electronic TD stores which were also used for new work. Combinators were either purpose designed units or circuits were built from discrete PO type relays. Wiring was also different, 1/052 was the safety circuit standard at one time and the colour was a rough guide to the age of the room i.e. dark green was 1950s or older, light grey was 1950s/1960s, light green or orange was 1970s. The 1970s also saw a different standard where green 1/044 was used, in the 1980s it was STC red or black double insulated single core closely followed by brown single on the Bakerloo resignalling and later still black or blue single core Raychem. The colours of wires in safety signal circuits have no meaning whatsoever! Other colours found in IMRs are yellow, roberta blue and green in 7/036 any of which can be earth or live, in the old days all the busbars were fed with green 19/036 singles, regardless of designation. Obviously metric replaced the old imperial standard in the later IMRs. Mechanically equipment racks and fuse bays also evolved from grey or green painted steel to unpainted aluminium and shapes changed to suit new standard layouts. In the newer IMRs circuits were fitted with miniature circuit breakers instead of fuses. The bottom line is that no two IMRs were/are identical even if the track layout was identical. Every IMR was unique, most in more ways than might be imagined. We had a saying on signals, if one of anything exists it is a standard! In general terms there were similarities between sites on a particular line, most Central line IMRs had the same sort of atmosphere, usually dim rooms with cream painted walls, District IMRs and Northern IMRs tended to smell of cooked Marley floor tiles which were stuck to the walls and ceilings while the Vic line IMRs were notable for being fully lined in aluminium sheet and wired predominantly in asbestos braided incoming cables. The one similarity with all IMRs was the floor tiles lovingly cared for by signal lineman who kept them polished with red cardinal. I can't recall ever being in an IMR that didn't have a red tiled floor. I'm sure I have missed loads of differences, it's nine years since I last saw the inside of an IMR. RT what you have said I don't disagree with the people I was discussing IMRs with call a relay a relay they don't think of all the different types and you can include the diagram there are a number then there are LOBs high speed scanning slow speed scanning it goes on.
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IMRs
Aug 18, 2013 13:41:52 GMT
Post by railtechnician on Aug 18, 2013 13:41:52 GMT
As I said I missed loads of differences, but I didn't leave out LOBs, I simply didn't specify them within electronic non-safety systems! If you start to detail the differences in kit to the nth degree you'll have an extremely long list. You might begin with the different types of air motor driving the lever shafts and the various different Martonair valves used to drive those air motors etc etc, different generations of other components of V frames such as contacts made of different materials and so on.
Even Westinghouse relays have been modified over the years such that although they may look the same and act in the same way they are different, for instance later relays may have less coils because the originals carried spares. A close examination of such relays in many IMRs would show differences between SEVs of the same spec for example!
By the way for anyone who doesn't know Ealing Broadway has an N2 frame, i.e. a converted N power frame remotely worked.
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IMRs
Aug 18, 2013 13:54:49 GMT
Post by hellocontrol on Aug 18, 2013 13:54:49 GMT
As I said I missed loads of differences, but I didn't leave out LOBs, I simply didn't specify them within electronic non-safety systems! If you start to detail the differences in kit to the nth degree you'll have an extremely long list. You might begin with the different types of air motor driving the lever shafts and the various different Martonair valves used to drive those air motors etc etc, different generations of other components of V frames such as contacts made of different materials and so on. Even Westinghouse relays have been modified over the years such that although they may look the same and act in the same way they are different, for instance later relays may have less coils because the originals carried spares. A close examination of such relays in many IMRs would show differences between SEVs of the same spec for example! By the way for anyone who doesn't know Ealing Broadway has an N2 frame, i.e. a converted N power frame remotely worked. You would have a list which would become a volume, by the way I have not heard of the X25 where was this used. I thought Ealing Broadway was an N2 from the start and not converted, Wembley Park had an N frame 55 levers next door to the signalman push button desk and this was converted from an L frame. As far as I know there are three kinds of N frame N A lot of manually worked frames and also a lot of remotely worked. N2 Ealing Broadway/Harrow North & South might be a few others Ruislip Gardens. N2M Edgware (proposed never commissioned) Epping and Debden.
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IMRs
Aug 18, 2013 15:56:07 GMT
Post by railtechnician on Aug 18, 2013 15:56:07 GMT
As I said I missed loads of differences, but I didn't leave out LOBs, I simply didn't specify them within electronic non-safety systems! If you start to detail the differences in kit to the nth degree you'll have an extremely long list. You might begin with the different types of air motor driving the lever shafts and the various different Martonair valves used to drive those air motors etc etc, different generations of other components of V frames such as contacts made of different materials and so on. Even Westinghouse relays have been modified over the years such that although they may look the same and act in the same way they are different, for instance later relays may have less coils because the originals carried spares. A close examination of such relays in many IMRs would show differences between SEVs of the same spec for example! By the way for anyone who doesn't know Ealing Broadway has an N2 frame, i.e. a converted N power frame remotely worked. You would have a list which would become a volume, by the way I have not heard of the X25 where was this used. I thought Ealing Broadway was an N2 from the start and not converted, Wembley Park had an N frame 55 levers next door to the signalman push button desk and this was converted from an L frame. As far as I know there are three kinds of N frame N A lot of manually worked frames and also a lot of remotely worked. N2 Ealing Broadway/Harrow North & South might be a few others Ruislip Gardens. N2M Edgware (proposed never commissioned) Epping and Debden. Hang on now and be careful, you started the thread and the subject is IMRs! So manually worked frames and signal cabins are not necessarily relevant to the topic as they tend to be attached to Cabin Relay Rooms, however, the distinction is somewhat greyed I feel. AFAIK Harrow was/is still a manually worked cabin which happens to also remotely control a power frame in the same room (it's more than 20 years since I was last there). Ealing Broadway is an IMR, N2 is the designation for a converted power frame, whether it was converted at the factory or in situ is irrelevant to the designation. Of course Ealing Broadway IMR is actually a cabin relay room because the programme machines, LOB and high speed scanning are all housed in the TD relay room next door which also has the P/Mcs for Hanger Lane Junction IMR ! AFAIK Ealing Broadway was originally worked remotely from a local console control panel in the cabin upstairs, it was one of my maintenance sites as a Picc TO so I was quite familiar with it. I believe the IMR would have been so designated even when locally worked just as Farringdon was. Of course Farringdon was a special case because the cabin controlled more than one site controlling everything from the outskirts of Kings Cross to Liverpool Street before it also took control of Aldgate IMR. Thus Farringdon had a cabin relay room and a local IMR. I can recall the old Wembley Park Cabin and its push button console, I have a feeling that when that was recovered following the resignalling in the late 1980s (I was Comms Installation Chargehand in those days so my involvement was installing and commissioning the SPTs on that job and the other Met/Jub sites) it was refurbished to become the Aldgate console in Farringdon cabin (I did the SPTs there too). As a Picc TO, Wembley Park was in my maintenance area (the entire Picc, Jub Charing Cross to Stanmore, District Acton Town to Ealing Broadway and Met Finchley Road to Wembley Park) so I used to do IMR maintenance there from the late 1990s until I retired and I cleaned all the frames in my area many times. X25 is the comms network over which the east end of the Picc is controlled. Later technology such as used on the Met/Jub from the late 1980s was the multidrop signal databus which also carried such things as train radio landlines and longline PA control and audio. AFAIR signalling non-safety on the databus used S2 scanning to talk to the site computers but I had little to do with the non-safety signalling on the Met/Jub not being based in Wembley Park depot. I wouldn't really want to split hairs but I'm sure you'll agree that the question that you first posed is far more difficult to answer than perhaps originally considered and even more so when looked at in detail! I think the definition of what constitutes an IMR is clear on paper but in practice it is not so clear cut unless taken literally i.e. a room containing an interlocking machine, literally a room with a V style frame because earlier types were not referred to as interlocking machines!
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IMRs
Aug 19, 2013 11:11:55 GMT
Post by hellocontrol on Aug 19, 2013 11:11:55 GMT
You would have a list which would become a volume, by the way I have not heard of the X25 where was this used. I thought Ealing Broadway was an N2 from the start and not converted, Wembley Park had an N frame 55 levers next door to the signalman push button desk and this was converted from an L frame. As far as I know there are three kinds of N frame N A lot of manually worked frames and also a lot of remotely worked. N2 Ealing Broadway/Harrow North & South might be a few others Ruislip Gardens. N2M Edgware (proposed never commissioned) Epping and Debden. Hang on now and be careful, you started the thread and the subject is IMRs! So manually worked frames and signal cabins are not necessarily relevant to the topic as they tend to be attached to Cabin Relay Rooms, however, the distinction is somewhat greyed I feel. AFAIK Harrow was/is still a manually worked cabin which happens to also remotely control a power frame in the same room (it's more than 20 years since I was last there). Ealing Broadway is an IMR, N2 is the designation for a converted power frame, whether it was converted at the factory or in situ is irrelevant to the designation. Of course Ealing Broadway IMR is actually a cabin relay room because the programme machines, LOB and high speed scanning are all housed in the TD relay room next door which also has the P/Mcs for Hanger Lane Junction IMR ! AFAIK Ealing Broadway was originally worked remotely from a local console control panel in the cabin upstairs, it was one of my maintenance sites as a Picc TO so I was quite familiar with it. I believe the IMR would have been so designated even when locally worked just as Farringdon was. Of course Farringdon was a special case because the cabin controlled more than one site controlling everything from the outskirts of Kings Cross to Liverpool Street before it also took control of Aldgate IMR. Thus Farringdon had a cabin relay room and a local IMR. I can recall the old Wembley Park Cabin and its push button console, I have a feeling that when that was recovered following the resignalling in the late 1980s (I was Comms Installation Chargehand in those days so my involvement was installing and commissioning the SPTs on that job and the other Met/Jub sites) it was refurbished to become the Aldgate console in Farringdon cabin (I did the SPTs there too). As a Picc TO, Wembley Park was in my maintenance area (the entire Picc, Jub Charing Cross to Stanmore, District Acton Town to Ealing Broadway and Met Finchley Road to Wembley Park) so I used to do IMR maintenance there from the late 1990s until I retired and I cleaned all the frames in my area many times. X25 is the comms network over which the east end of the Picc is controlled. Later technology such as used on the Met/Jub from the late 1980s was the multidrop signal databus which also carried such things as train radio landlines and longline PA control and audio. AFAIR signalling non-safety on the databus used S2 scanning to talk to the site computers but I had little to do with the non-safety signalling on the Met/Jub not being based in Wembley Park depot. I wouldn't really want to split hairs but I'm sure you'll agree that the question that you first posed is far more difficult to answer than perhaps originally considered and even more so when looked at in detail! I think the definition of what constitutes an IMR is clear on paper but in practice it is not so clear cut unless taken literally i.e. a room containing an interlocking machine, literally a room with a V style frame because earlier types were not referred to as interlocking machines! Thanks re the X25 beats the M25 anytime. I should have said Wembley Park had 59 levers, Harrow still in operation has three SBs both the North & South are called IMRs but when commissioned were known as subsidiary SBs the levers that you see moving in the Station box are part of the same frame it's just that they are being controlled by the route setting levers at the London end. The PBD from Wembley Park did go to Farringdon for the Aldgate area and you are 100% right the original question posed has grown just like this thread. Ealing Broadway was originally planned to have a 47 lever N frame but the Signal Engineer Robert Dell chase the site for the first push button desk so an N2 frame was used and it must have been made up from parts of a frame from somewhere typical of LT. Both Ealing Broadway & Wembley Park were commissioned before V frames came in. High Barnet now sent to history was an N frame but when converted remained an N frame some will say N2 because of the remote control but I have not seen this documented.
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IMRs
Aug 19, 2013 15:02:53 GMT
Post by Harsig on Aug 19, 2013 15:02:53 GMT
... Harrow still in operation has three SBs both the North & South are called IMRs but when commissioned were known as subsidiary SBs... I would contend that Subsidiary Signal Cabin is still the correct designation for Harrow North & South Cabins and it is incorrect to refer to them as IMRs. From an operating department point of view the difference (so I was taught) was in the staff required to work the frame in the event of a failure of remote operation. With an IMR the frame must be worked by a technical officer acting on the instructions of an operating official. With a subsidiary cabin only a signalman is required and to this end subsidiary cabins are divided into two rooms, an operating room and a relay room. The signalman can access the operating room but not the relay room just as in a normally staffed signal cabin.
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IMRs
Aug 19, 2013 17:31:19 GMT
Post by hellocontrol on Aug 19, 2013 17:31:19 GMT
... Harrow still in operation has three SBs both the North & South are called IMRs but when commissioned were known as subsidiary SBs... I would contend that Subsidiary Signal Cabin is still the correct designation for Harrow North & South Cabins and it is incorrect to refer to them as IMRs. From an operating department point of view the difference (so I was taught) was in the staff required to work the frame in the event of a failure of remote operation. With an IMR the frame must be worked by a technical officer acting on the instructions of an operating official. With a subsidiary cabin only a signalman is required and to this end subsidiary cabins are divided into two rooms, an operating room and a relay room. The signalman can access the operating room but not the relay room just as in a normally staffed signal cabin. I have always considered them as subsidiary cabins but on the North cabin entrance door it states IMR and that has been there for a number of years.
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IMRs
Aug 19, 2013 18:48:23 GMT
Post by railtechnician on Aug 19, 2013 18:48:23 GMT
I would contend that Subsidiary Signal Cabin is still the correct designation for Harrow North & South Cabins and it is incorrect to refer to them as IMRs. From an operating department point of view the difference (so I was taught) was in the staff required to work the frame in the event of a failure of remote operation. With an IMR the frame must be worked by a technical officer acting on the instructions of an operating official. With a subsidiary cabin only a signalman is required and to this end subsidiary cabins are divided into two rooms, an operating room and a relay room. The signalman can access the operating room but not the relay room just as in a normally staffed signal cabin. I have always considered them as subsidiary cabins but on the North cabin entrance door it states IMR and that has been there for a number of years. Just because there is an IMR label on the outer door does not make it an IMR, quite often the sign is there as a location guide for those who are unfamiliar with the site. Consider the street entrance to Down Street which has IMR on the door. To reach the IMR one must negotiate the spiral staircase, passageways and platform area to reach the IMR. Kings Cross Picc is perhaps a more fitting example, it is an IMR but AFAIR the V frame could be worked by a signalman unaccompanied as the outer door only gave access to the frame, stick phone panel and auto telephone. Ealing Broadway similarly allows access to the frame and the telephone but the relay room behind the frame and the other equipment in the separate TD relay room which make up the IMR are inaccessible.
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IMRs
Aug 19, 2013 21:56:38 GMT
Post by WLX568 on Aug 19, 2013 21:56:38 GMT
X25 is the comms network over which the east end of the Picc is controlled. Later technology such as used on the Met/Jub from the late 1980s was the multidrop signal databus which also carried such things as train radio landlines and longline PA control and audio. AFAIR signalling non-safety on the databus used S2 scanning to talk to the site computers but I had little to do with the non-safety signalling on the Met/Jub not being based in Wembley Park depot. The Met and Jubilee lines used a DS1000 network to connect all the site computers to the comms machines at Baker Street, all of which were HPs, either A600, A900 or A990. The interface between the site computers and the lever frames differed, the met Main and Jubilee used S2, Aldgate used TEML-40 (as did the Bakerloo on its own DS1000 network) and the Met City used a Serck interface. The supervisory cable between all the sites was a 28pr comms cable, great fun to work on!
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IMRs
Aug 20, 2013 8:04:39 GMT
Post by hellocontrol on Aug 20, 2013 8:04:39 GMT
I have always considered them as subsidiary cabins but on the North cabin entrance door it states IMR and that has been there for a number of years. Just because there is an IMR label on the outer door does not make it an IMR, quite often the sign is there as a location guide for those who are unfamiliar with the site. Consider the street entrance to Down Street which has IMR on the door. To reach the IMR one must negotiate the spiral staircase, passageways and platform area to reach the IMR. Kings Cross Picc is perhaps a more fitting example, it is an IMR but AFAIR the V frame could be worked by a signalman unaccompanied as the outer door only gave access to the frame, stick phone panel and auto telephone. Ealing Broadway similarly allows access to the frame and the telephone but the relay room behind the frame and the other equipment in the separate TD relay room which make up the IMR are inaccessible. I only mentioned what was on the door there is at least one other location where there is a sign on the door IMR but you have to go through a number of doors before reaching the actual IMR. Kings Cross again like you say like Ealing Broadway amongst other places is separate, perhaps they should rename them SER so as to avoid any confusion to the untrained.
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IMRs
Aug 20, 2013 8:40:32 GMT
Post by railtechnician on Aug 20, 2013 8:40:32 GMT
X25 is the comms network over which the east end of the Picc is controlled. Later technology such as used on the Met/Jub from the late 1980s was the multidrop signal databus which also carried such things as train radio landlines and longline PA control and audio. AFAIR signalling non-safety on the databus used S2 scanning to talk to the site computers but I had little to do with the non-safety signalling on the Met/Jub not being based in Wembley Park depot. The Met and Jubilee lines used a DS1000 network to connect all the site computers to the comms machines at Baker Street, all of which were HPs, either A600, A900 or A990. The interface between the site computers and the lever frames differed, the met Main and Jubilee used S2, Aldgate used TEML-40 (as did the Bakerloo on its own DS1000 network) and the Met City used a Serck interface. The supervisory cable between all the sites was a 28pr comms cable, great fun to work on! Oh how I recall the trials and tribulations of that cable, I had to route the longline Met/Jub PA control lines through it between Finchley Road and Wembley Park and onward to Stanmore as there were no suitable spare pairs in the main telephone cables in the late 1980s before we began the main cable network uplift. The Stanmore branch was particularly bad, as fast as I connected up the circuits from Baker St control room CER to commission Kingsbury to Stanmore the signal installation supervisor kept diverting them away from the PA racks into the local signalling interfaces as he thought the Baker Street SCC was going to control them! I didn't have the same trouble when we later had to route train radio landlines through the cable. On the Central line we installed a dedicated RPA (remote public address) cable with an 8 pair tail dropped to each station PA rack and we really should have done the same on the other lines, sharing the Met/Jub signal databus was less than ideal but we repeated the habit when we routed train radio landlines in the signal databus cable between Earls Court and Cockfosters.
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