Garden Train - Arduino / Wireless DCC

Intro: Garden Train - Arduino / Wireless DCC

A home made G-scale DMU train runs on brass track around the garden. Unfortunately, the lack of good contact is quite a nuisance to smooth running. To avoid the need for electrical contact, I have converted the train to run off a 6000 maH battery pack (recharger for phones etc).

The DC motor runs around 250 mA so the Lenz standard decoder 10231 at 1 Amp output is fine. I also installed a MRC 1662 DCC diesel sounder in parallel with the 10231.

The transmitter is simply a RFu328 mounted on strip board and a series of push buttons to select functions along with a potentiometer to control speed.

The receiver is another RFu328 that decodes the wireless transmission and converts data into standard NMRA DCC format. It is in fact, small version of my DCC controller (see other instructable).

A small scale DCC booster is included using the SN7544110ne quad h-bridge chip which suits the motor in use.

To get a push-pull output swing of 20 volts (+- 10v), the DCC signal is fed into one input and an opposite, complimentary signal is fed into the other input. The resulting output provides the DCC output for the motor and all functions. More detail to follow

STEP 1: Transmitter

The circuit diagram is attached.

Components used:

RFu328 Arduino / SRF wireless module : £16 (Wireless Things Ltd)

AMS1117 step down from 4.5v to 3.3v : £2.55 (ebay)

Push buttons (NO momentary) 10 off : £10.62 for pack of 10 from Farnell

Potentiometer 4k7

3 x AA batteries

On/Off switch and LED

Total cost of components for transmitter, including box, approximately £40

The Arduino code is attached.

send_dcc_via_rf_to_loco_jun2016.ino

STEP 2: Receiver

The circuit diagram of receiver is attached.

Components used:
RFu328 Arduino / SRF wireless module : £16 (Wireless Things Ltd)

AMS1117 step down from 4.5v to 3.3v : £2.55 (ebay)

Step up from 5v to 12v at 6 Watt : £3.00 (ebay)

SN754410NE 4 Channel Half-H Bridge Driver IC : £2.30 (ebay)

EasyAcc 6000 mAh Ultra-Slim External 5 volt Battery : £13.99 (Amazon)

Total cost (not including DCC decoders) is around £38

The Arduino code is attached.

receive_dcc_via_rf_to_loco_jun2016

Comments

[JustinA78]

Alrighty, going to try using blue tooth control via cell phone. I'm essentially using the same route you used for RC but instead of mrc will be using a dcc sound decoder.

[JustinA78]

Another question I have is any way to replace the wireless module with say blue tooth and use engine driver or something similar to run it via a smart phone?

[BillC35]

Yes any other wireless comm would work as the DCC part is generated onboard the train. All you need to transmit is the instructions.You would probably have to make your own app on a phone - I do not know how Engine Driver transmits data.

[JustinA78]

I have a question, seeing as the firm that produces the RF28 is no longer, is there a replacement you can suggest? Thank you!

[BillC35]

Please refer to my instructable 'Model Railway DCC Arduino wireless commands on a dead rail system' for details of the nRF24 replacement for the obsolete RF28.

[JustinA78]

Thank you so very much! I look forward to trying this out.