0 Gauge Class 33 Scratch Build - Part 8

There is more than one way to add accessory control to a model locomotive. I am not intending to use DCC as the track plan and range of locomotives will be very limited. It has been suggested that a small Raspberry Pi  computer is a good way of providing remote control of the loco accessories. I might consider that in future but for now I purged my existing stock of components.

This is my second implementation. The first had a pulse width modulator electronics circuit for adjustment of LED brightness (Search 'led dimmer circuit' for examples). This was driven from 4 x button cells with a separate AA cylinder battery to drive the fan motor. The dimmer circuit was not really required as the LEDS gave best light on full illumination so, to simplify matters it was removed. LEDS are now driven from 2 x AAA batteries with the fan power drawn off of 1 of the batteries.

Below is a view of the controls through the hole in the roof with the translucent access panel removed. You would not believe I spent nearly 25 years in electronics design and manufacture when you look at this birds nest of wiring. I'm not proud of it but it does work!

The switch bank is for power, leds and fan. The bluetooth speaker has an internal rechargeable battery and is controlled remotely from an iPad.

When it comes to operation, the fan and appropriate LEDS are activated/deactivated manually from the switch bank before/after the journey and the sound controlled during the journey.

I am not concerned that 'the hand of God' is evident because it mimics the prototype where the roof panel was removed for some maintenance jobs on the engine.

To Part 9.

To Part 1 of this series.