It has long been a task to get Lambourn's platform mounted starter signal into operation. In fact the original non-working signal was broken some time ago.
A fit of enthusiasm, and a wet weekend (Well two actually) has seen the task completed.
the signal was sited at the end of the platform, and so was unusual in that the balance weights were mounted high on the post, an early example of 'elf and safety'!
I confess that the model is actually too tall, ( it should be a bit lower for the driver to sight the arm from below the canopy, but that'll be our little secret eh?
The arm is actuated by a servo drive, and illuminated by a tiny (1.6mm x .85mm x .65mm) surface mount LED. I destroyed one as the cast brass post held too much heat which destroyed the LED. Finally I attached two fine enamelled wires and these are hidden in a filed slot in the post, which was finally filled with thick paint. The wires are carried below the platform level and soldered to thin PCB, from which normal layout wires connect to a battery pack below the layout. The fine enamelled wires are protected by 'potting' them in rapid setting resin.
At the time the pictures were taken I still have to fit the ladder and finial, but it has been a satisfying project and transforms the layout.