What does 'H' sign board in Indian railways indicate?
'H' sign is present in station boards or some yards preceding to the station boards in Indian Railway system to indicate that upcoming station is a halt.
Main characteristics are :
No yard/change /points involved.
No...
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wait for line/signal clear.
No points man/cabin located at the station. Train halts at main line itself.
Guards/ALP/Timer based signal is enough to start the train after the halt in such cases and these stations are not used for other purposes like granting or receiving line clear etc., there are no signals provided here, only limited staff for ticket vending is available as per train timings.Train halts at the main line itself for designated period of time and moves automatically without waiting for any indication from station staff.

(First pic credit to blogger, kumar vaibhav)