block post (signal box) simulator

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This simulator recreates absolute block working, using real block instruments. It is programmed to replay interactively a section of a signal box register - all the way from the train being offered from the box in rear, to getting 2-1 'train out of section' from the box in advance. It is easy to reprogram it to do a different section of register.
In order to 'see' the trains, it is connected to an illuminated diagram, or track circuit indicators. I'm afraid you'll have to imagine the tail lamps!
It is built in a modular fashion; some modules represent the adjacent block posts and handle the bell ringing, whilst others simulate the passage of the train over the illuminated track diagram. The first simulations I built could only do straight up and down working, but it is now possible recreate more interesting layouts.
I've had it working with a variety of three-wire, three-position block instruments - LNWR Fletchers, Tyers permissive, LNER black box and GCR-type pegger and non pegger. In addition, block controls - such as Welwyn control - have been implemented with some of these instruments.