Model railway running under computer control using the laptop to send commands over the USB port to the Arduino, which then does PWM to control the speed of the train. There were a few hiccups along the way not least of which the Arduino crashed repeatedly when the train started moving it appears that the power pack I was using didn`t like having its load being PWMed, causing voltage problems.
Click here to download the full size of the above Circuit.
I resorted to running the Arduino off the USB supply, disconnecting the common 12V power input to the board, and just using that external power pack to provide power for the direction change relay and output to the loco. Make sure that you keep the ground connected though, as the Darlington TIP120s need that to be common in order to work. The eventual use for this project is to automate the model layout in the Corris Railway Museum, and allow visitors to put coins in a slot and the train will then run for a number of returns depending on the coin put in. More coins the train runs a little quicker. The software allows for reed switches at either end of the line for reversing, as well as reed switches for stations. The hardware driver circuit is shown here in the schematic below (I know it`s pretty rough, but it`s as good as I can do at short notice), and photo of the really dodgy looking breadboard prototype.
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: