Ok, I have read alot about signals these last days, so I have summarized underneath what I found.
Could you find more about the signal on the left picture here: http://www.ekeving.se/si/mek/index.html?
That is a so called "plate signal" in the lack of a better translation. I have made a shortshort description underneath
Do you have any idea what sign could be used for early drive-by-sight signal?
Maybe fig. 17 (Grön bansignaltavla och dess placering) on this link:
http://www.ekeving.se/t/sao41/sif.html?
The "one way sign" could be fig. 10 (Spårspärrskärm) on that link?
"End of choose" could be fig. fig.9 b2.
What sign is usual on gates over railway (gates of depot and such) ?
I dont understand which sign you mean.
Firstly some comments:
Combined signal was to my knowledge never used with semaphores. First with track circuit blocks, a signal could show the state of the next signal.
The maxspeed should be quite higher than 80kmh for the pre ATC signals, like 160kmh as its in pakbritain.
Time interval I nowhere found where ever used (only in the exceptions I have descibed in earlier posts), so I think that this working method should not be used.
Token block was also only very very rarely used and therefore I think should not be included. Although the one train staff also where very rarely used, I think that could be very usefull in Simutrans.
The telegraph has been used since the beginning, using a system called Tam which best describe as both absolute block signaling and later track circuit. Everywhere I read, Tam is what has been used. Therefore I think the working methods of Pak.Sweden should be:
Absolute block
Track circuit block
one train staff (very handy)
cab signal
Moving blockI have some corrections which I will try to explain via the underneath timeline:
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*Dawn of railways* Communication station to station via telegraph (absolute block)All signals has to be set manually = signalboxes have very short range
*Dawn of railways* Signalman with flags (stop/clear, maybe also a choose version (with no aditional choosegraphics))
1858 T-semaphore (stop/clear, maybe also a choose version (with no aditional choosegraphics))
1858 Platesignal (stop/clear, maybe also a choose version (with no aditional choosegraphics))
Semaphores where mainly signalling wether a train where allowed to enter the station.
When they wasnt a T-semaphore, they where placed around 50 meters outside the furthermost point.
Platesignals where painted red and only facing one direction, and could (instead of a semaphore) be placed on either side of a station (outside the furtherst point).
T-Signal meanings:
Left wing horizontal: Stop
Left wing pointing down: Drive
Both wings pointing down: Points are locked to main track and is "ungarded" (mostly used when the station is closed)
Also, the left wing could hang vertically down which would mean Drive and proceed, however that was seldom used at stations (and was not allowed on tracks with junctions)
Platesignal meanings:
Red plate facing approaching train: Stop
Turned along the track: Drive
1880 Presignals (clear/caution)
A green plate facing the train would mean caution, no green plate would mean clear.
1888 "Hävstångsställverk" (absolute block)1890 "Ställbock" and "Vevställverk" (absolute block)All three are mechanical signalboxes of different types and sizes.
"Ställbock" is a very small signal"box", or rather a switchgear, often bolted to a wall or where standing directly on the platform. Usually only manouver a couple of points and signals.
"Vevställverk" is a signalbox where the mechanism to change tracks and signals where based on wheels. Length up to 350 meter
"Hävstångsställverk" is a signalbox that uses big arms to change the states of signals and tracks. Length up to 550 meters
1890 Twowinged semaphore (choose signal: stop/clear-main/clear-div)
The two winged semaphore had the logic that when the upper wing alone pointing 45 degres down, the train will enter the main track. If both wings are pointing 45 degres down, then the train will enter a sidetrack on the station.
1906 All semaphores now points upwards1907 Threewinged semaphore (choose: stop/clear-main/clear-div)
When clearance is given with three wings, it means sidetrack/shorted track. This signal could in principle replace the twowinged semaphore.
Later, when Simutrans trains can reassemble, three wings would be the "call on" aspect.
1910 Electric Signalbox (absolute block)Could manouver signals at mutch bigger distance, however only signals inside his sighting distance. When track circuit blocks becomes available, the distance could be much higher.
1910 Presignals can alert for more wings on the forthcoming signal (clear/caution/(cant be simulated now, but caution for sideway))
By adding a wing to the presignal, it could alert the traindriver if the main signal to the station would send him to main track or side track
1920 Track Circuit Block1920 Electric Signalbox (extended range, track circuit block))1920 Track circuit block signals (stop/clear/caution)
These first track circuit block signals had these states:
Red solid light = stop
Blinking green = caution
Green solid light = clear
(
http://www.ekeving.se/lb/aut/index.html)
1922 Modern signalstwo light: stop/clear (solid-red/solid-green)
three light: Choose signal: stop/clear (solid-red/2xsolid-green)
four light: Stop/clear/caution (solid-red/solid-green+blinking-white/solid-green+blinking-green)
five light: Choose signal: Stop/clear-main/clear-div/caution-main/caution-div (solid-red/solid-green+blinking-white/2xsolid-green/solid-green+blinking-green/3xsolid-green)
When Simutrans trains may reassemble, the 3xsolid-green should become the "Call On" aspect.
presignal, two lights: clear/caution (blinking-white/blinking-green)
An optional permissive signal could be:
Five light: three aspect permissive signal: Stop/clear/caution/Callon (solid-red/solid-green+blinking-white/solid-green+blinking-green/3xsolid-green)
Do note that some of the very early modern signals could have some variations (eg yellow light, signalling the caution for sideway) but I find it very dificult to find good documentation
1930 Modern presignals get an extern yellow lamp to alert for sideway entry (clear/caution/(cant be simulated now, but caution for sideway))
1975 Modern presignals get three lightsA green light are added to the signal itself (now has two green and one white), removing the yellow "caution for sideway" lamp.
States:
clear/caution/(cant be simulated now, but caution for sideway))
1980 ATC (cabsignalling)As track circuit signals but speed limit is now raized to 250kmh
All signals should have a yellow plate between the rails (like on pictures of this google search:
https://www.google.dk/search?q=atc+baliser&espv=2&biw=1786&bih=901&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMIo6uDpYSbyQIVARUsCh2QwAW22010 ERTMS (Level 2)No signals needed
Future ERTMS (Level 3)No signals needed
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Questions:As to the five aspect choose signal I have a question: will the "Clear-main" be showed also when the train is stopping at the station, or is there a way to make this state only show when when the train drive through the station (using the main route)?
Regarding the 3 light choose signal, is that needed along with the 5 light choose signal?
Will there be implemented a signaltype that works as a T-signal?