Monthly Update: September 2026

September 2026 update. Well, a big pause since the last update in July 2025! Apologies for this, but as oSB development is still a one-man-band until the first release, relocating back to the UK and sorting house and commitments meant a pause on this work. However, that is now largely out of the way so expect regular updates to begin again and rapid progress on the project.

The thumbnail shows the High Barnet depot train number indicator, which was used on the Northern line underground depot to indicate which driver should next pull forward to start their shift. It uses three stencil route indicator heads driven by 30 heavy duty DC relays (5 per glass enclosed relay tank, originally run on 100 V AC via an supply resistor and rectified using their flyback diodes, but here using 24 V DC). This is now an exhibit at the London Transport Museum depot at Acton and can be seen running during their open days, the next being September 25 - 27. openSignalBox has provided a temporary compact controller which sequences valid numbers to display, and is designing the full integration with a programme machine to demonstrate the prototypical operation. The existing computer simulators at the museum, which are used to demonstrate the Elephant and Castle and Marble Arch miniature lever frames, are being evaluated for replacement with the openSignalBox software when ready.