Leaving point motors behind I have moved on to the colour light signalling.
The signals won't be installed just yet - I'll wait until the baseboards spend most of their life the right way up for that - but the clever bits are going in.
The up line (left-right) has a signal with a route indicator (feather) which is illuminated when the train is routed to the bay platform.
The down line has a signal at the end of the platform with a second one on the bay.
Ground signals are situated to allow shunting moves between the bay and the layover siding.
The control circuitry also includes signals at the entrance to each end of the fiddle yard although as these are off-scene, they only exist as red repeaters on the control panel.
The MAS signals are controlled by modules from Heathcote Electronics which do all the hard work. The only complicated bit involves the up main to down main (and then to the bay platform) routing which needs to switch a number of circuits:
- Up main crossover live frog - by switch on point motor
- Down main crossover live frog - by switch on point motor
- Control panel point indicator LEDs - by MasterSwitch output
- Up & down main crossover point motors - by MasterSwitch output
- MasterSwitch operation - Panel switch (DPDT)
- Relay board for extra switching - Panel switch DPDT
- Up main signal feather - Relay board
- Clear up main signal - Relay board
- Hold down main signal red - Relay board
- Hold bay signal red - Relay board
A pair of 12V DPDT relays will provide the extra switching needed when the crossover is reversed.
The parts are shown above and will be built into the control panel real soon now .