I thought folks might be interested in a couple of photographs of the new MERG CBUS based DCC system. This uses a CANBUS (originally developed for the automotive industry) to transmit the signals from the handset to the command station which then generates the completely standard DCC signals on the track. The advantage is that this is the same wiring bus as I using for controlling the rest of the layout using other MERG CBUS boards. Ultimately I should be able to run the whole layout with 6 to 8 wires between the boards.
- Two for the DCC signal.
- Two for the CBUS.
- Two for a 12v DC pair to power the modules.
- I'll probably end up with another pair for a 16AC as this can then be used if I need power anywhere else.
There are three components to the DCC system, A command station which is a simple PCB costing around £25 to build, a number of handsets which are available as a kit for £38 and a soon to be released booster which will be another ~£25. Without the booster you are limited to pulling about 1.5amps in total but that is proving adequate to run a couple of trains around Empire Basin with no problems.
The command station is pretty straight-forward to build being just a single board and convention 'through hole' mounting of components. As usually you need to take some care with your soldering and reading the instructions but it isn't beyond the skills of a beginner.
The handset on the other hand is a good deal more complex requiring the use of surface mount components. These look a bit scary to start off with and I watched several video clips on Youtube demonstrating how to solder a chip with 20 pins down one side an inch long onto a board with trepidation before having a go. In the end I found it wasn't as bad as I feared, a combination of a circuit board covered with a solder resistant surface (except that is where you need to solder!) and the smallest soldering iron bit Maplins had did the trick. I also bought some de-soldering wick which came in handy on the occasion when I did manage to bridge a connection. In the end the little handset really does feel like a quality part and is a credit to those involved with the design. The knob is positioned nicely for the thumb and you can easily drive the loco with one hand. The push buttons are very easy to work and the typical operations of selecting a loco or turning a function on and off are all quite logically and take very little getting used to. There are a couple of limitations with the current version of the firmware around taking control of a loco already assigned to another handset but these are all developments due in forthcoming releases.
A combination of the MERG command station, the CAN-USB interface which allows a PC to talk to the CBUS and the Java Model Railway Interface (JMRI) also allows the use of an Android phone or (if you want to sell your soul to Apple) a Iphone as a throttle. I'm tempted, but not tempted enough to want to part with the cost of a loco kit just to try it!