3
2. Here is the board from part 1 without the recorder
modification. The highlighted areas were not used
in the first project but will accommodate the parts
needed to make the recorder.
3. The photo at the top of the article [1] shows the
completed board with the blue 12-volt relay shown
here. The black relay next to it is a 5-volt unit that fits
into a 16-pin IC socket.
things that could be done once you have an easy to use and
reliable circuit for controlling trains. I considered a number
of things but the most interesting modification was to add a
memory chip to the circuit so that I could use it to record a
train-running session and then play it back over and over.
The modifications to the original circuit that I show here in part
2 do exactly that: turn the device into a Record/Playback unit
that lets you run the train in a complex pattern composed of
forward movements, backward movements, stops, slow-speed
running, higher-speed running, and so on. You can record all
these actions so that it can be played again and again. Ten or
more minutes of running can be recorded and stored indefinitely
for playback.
I use an isolated section of track as a “sync” block. I can con-
trol power to this block by a relay in the circuit. Producing a set
of train motions that start and stop in this block gives a very
reproducible sequence of movements can be played back.
2
PICAXE circuit part 2 - 2
MRH-Jul 2014
