RailWest

Are you looking just for the internal colliery sidings plans, or including the main S&DJR running lines as well? What about the new "Pictorical Atlas....." from Strathwood ? https://strathwood.co.uk/products/a-pictorial-atlas-of-the-somerset-dorset-joint-railway

Sorry, missed that :-) But it would give an ideal opportunity to demonstrate a lever which locked another one 'both ways', as well as showing that sometimes the release of one lever is reliant on the prior use of two (or more) other levers.

What about a FPL ?

>>>...the points position must correspond to that signal's aspect..... Not strictly true surely? For example, if a point is set 'normal' then the signal(s) for that route may be 'on' or it may be 'off'.

If that was the Up Starting on the Down platform, then IIRC it was just a straight post.

I've attached a side view of the one which used to exist at Yeovil Pen Mill, although it may well be of course that bracket dolls used a different method than straight posts.

You may like to read pages 86 and 87 of John Owen's "Life on the Railway". Apparently Hopmead Siding was installed to feed coal drops for a new (1930s) adjacent Co-op coal depot. It had little use by 1948 and had been closed "soon afterwards" and had been lifted by 1953. There is a nice Hugh Ballantyne rear view of most of the signal gantry on page 86, but this shows what was clearly a post-MR replacement. Although looking very LMS-ish with UQ arms on tubular posts, be careful that the WR replaced several signals in the Bath Stn/Jcn area in BR days and these used LQ arms and tubular posts also, but with WR-style finials. You may need to look at more photos than I've had time to seek out to see what would be more appropriate for your period.

The attached OS 25" 'snip' shows the Hopmead Siding and IMHO it is quite clear from there that the siding went through the 'arch'. Sadly I can't find a date for that map.....

As drawn in an original LMSR diagram the 'arch' would appear to have straddled the Hopmead Siding (although that had been lifted by the time of the diagram copy). My suspicion is that Richard has drawn the bracket further in rear of crossover 9 than was actually the case, as disc 6 was at its foot. 12 was for the Up Main to Midford and 20 was the Up Main to Weston. 8 was for the Shunting Neck and the presence of the lower distant arm would suggest that it was for moves across 9 onto the Up Main towards Weston, with 6 presumably doing moves ahead towards 13?

Cooke merely records it as being lifted 'by 1960'.

...or perhaps you just got the polarity the wrong way round? After all, they are Diodes :-)

But...what then happens if a shorter train goes from L to R and never reaches the relocated B? In effect the system needs to detect 3 conditions:- 1. Train approaching (strike-in) 2 Train passing over the point (continuous detection) 3. Train clear of the point (strike out) 1 and 3 are easy, it's the 2 that may be harder :-)

I'm confused now :-) As drawn, your uni-directional line is for traffic moving from L to R. The LOS board, as drawn, applies to 'wrong direction' traffic from R to L. Clearly you do not want the traffic moving from L to R to be still over the point when it moves back to normal. But if traffic goign 'wrong direction' from R to L inadvertently passes the LOS board, then why would the points be moving anyway? And if they were, and the train was derailed, well isn't that purpose of the points anyway?

Well, the first thing that seems 'obvious' - unless I've misunderstood something - is that if B is only 2" beyond the point, then as soon as the front of the engine passes over the point will start to reverse again long before perhaps even the engine, let alone the first carriage, is clear of the point. What you need to create IMHO is the equivalent of a track-circuit extending from A to B, so that once the train runs onto the pseudo-TC at A the point reverses and is then held reverse by the continued occupation of the TC until its tail end clear the TC at B. Maybe several 'A's at intervals between A and B would do the trick ?

What diagram please?

It should be noted perhaps in this context that, where a signal 'height' is quoted in some official document (eg a Signal Instruction or similar), AFAIK the practice was for the figure quoted to relate to the height of the arm above the rail head. The actual post of course would extend some (variable) distance further above the arm, and if the post was set back some way from the track on an downward-sloping embankment than the visible part could be even longer still. Conversely, some signals quoted with a relatively high-ish height might actually be quite short posts, but stuck high up on the side or top of a cutting.

No need to nudge, I'm here already....:-) I would agree that the PSR shows 55. Sadly I don't have the answer to the signal post height, as such details are not recorded in any known records other than occasional references to replacements in some Signal Instructions. I know that at least one S&DJR simulation was produced a few years ago, so maybe the author of that (is 'author' the right term, or could it be 'creator' perhaps) may have the answer already.

I've broadened my research now to include the S&DJR's use of Electric Repeaters in general (not just Arm and Lamp) and an initial write-up can be found here for those who are interested:- www.trainweb.org/railwest/railco/sdjr/sigmisc.html#repeaters Comments, corrections and extra information always welcome ! Admittedly there is a lot more to this subject, especially with the early years, but I don't really have the time at the moment to delve into all the ramifications in details. Primarily I just want to write-up a 'general overview' for those who may want a simple explanation of the basics.

I've broadened the topic now to Electric Repeaters in general and an initial write-up can be found here for those who are interested. www.trainweb.org/railwest/railco/sdjr/sigmisc.html#repeaters Comments, corrections and extra information always welcome !

>>> What you really want is not the box diagram - it's the wiring diagrams for the box - but those are almost invariably long gone. Sadly, you are right - almost none are known to exist, and those that do are merely for parts of the installation :-( >>> You can't rely on diagrams even today to tell you whether a signal is repeated.... I think that depends upon age and BR Region. Certainly IMHO it seems to have been standard BR(S) practice to include such detail on box diagrams, whereas BR(WR) never did (which is not helpful when they replaced some of the S&DJR diagrams). >>> What is more commonly shown on diagrams is "HNC" (Home Normal Control).... Not something that I have ever seen on SR/GWR diagrams, though I know that it was done elsewhere. To be honest, apart from 'upgrades' done in the Templecombe Jcn area, most S&DJR double-line boxes did not even have 'Line Clear' releases and even 'Tablet Out' releases were not universal on the single-line sections until quite late, so I doubt that they had much by way of 'sophistication' in their controls. >>>..sometimes a whole set of lamps would be connected in series and indicate on a single repeater...... There were 3 instances of that practice that I have found so far on the S&DJR.

[Cross-posting from the S&DJR forum.] I am researching the extent to which the S&DJR provided Arm and/or Lamp Repeaters in their signal-boxes (and some GFs.) This is not an easy subject to examine, as most of the detail comes from information listed on signal-box diagrams, a practice which does not seem to have become common until about the 1930s. Even in the 1950s some diagrams had no such detail at all, but its absence can not be taken as a definite indication that no such repeaters were provided - it may be just that the original diagram negative was never updated. My general impression is that initially the provision of Arm Repeaters was limited to Distant signals (not surprising perhaps, given their remote locations) and even then not all of those. Arm repeaters for Stop signals did exist in later years at some locations, possibly because of signals being moved further out; there were also a few provided on signals which IMHO should not have needed them, so maybe it had become the practice in BR days to provide them as a matter of course when making alterations? Lamp Repeaters appear to have been very scarce - initially I found only six! Even Distant signals did not appear to have them as a rule, which I find strange - after all, if a train is approaching at night and the lamp is out and the driver has lost his bearings, then he's going to get a shock when the first he sees is the red light from a Home signal, so that extent I would have considered Lamp repeaters perhaps to have been even more important than Arm repeaters for Distant signals. Although quite a few photos do exist of S&DJR signal-box interiors which show some repeaters, it is not always easy to determine their function and to which signal(s) they apply. Often the photos show only part of the instrument shelf anyway, so the record is incomplete. Any thoughts and/or S&DJR-specific information would be appreciated - thanks!

I am researching the extent to which the S&DJR provided Arm and/or Lamp Repeaters in their signal-boxes (and some GFs.) This is not an easy subject to examine, as most of the detail comes from information listed on signal-box diagrams, a practice which does not seem to have become common until about the 1930s. Even in the 1950s some diagrams had no such detail at all, but its absence can not be taken as a definite indication that no such repeaters were provided - it may be just that the original diagram negative was never updated. My general impression is that initially the provision of Arm Repeaters was limited to Distant signals (not surprising perhaps, given their remote locations) and even then not all of those. Arm repeaters for Stop signals did exist in later years at some locations, possibly because of signals being moved further out; there were also a few provided on signals which IMHO should not have needed them, so maybe it had become the practice in BR days to provide them as a matter of course when making alterations? Lamp Repeaters appear to have been very scarce - initially I found only six! Even Distant signals did not appear to have them as a rule, which I find strange - after all, if a train is approaching at night and the lamp is out and the driver has lost his bearings, then he's going to get a shock when the first he sees is the red light from a Home signal, so that extent I would have considered Lamp repeaters perhaps to have been even more important than Arm repeaters for Distant signals. Although quite a few photos do exist of S&DJR signal-box interiors which show some repeaters, it is not always easy to determine their function and to which signal(s) they apply. Often the photos show only part of the instrument shelf anyway, so the record is incomplete. Any thoughts and/or location-specific information would be appreciated - thanks!

Even shorter perhaps, circa-1900 the Up Distant for Highbridge 'A' box was underneath its own Up Home! Admittedly the latter was slotted as the Up Home for Highbridge 'A' and also 'B' had 'control' over 'A's Up Distant.

Ah well, that would fit Henstridge then :-)

...but none on the S&DJR :-)