The protected section of track can be as long or as short as desired and does not have to be the same length on both sides of the crossing. The circuit works in both directions and can be connected to other grade crossing circuits to provide fully automatic protection for multiple track crossings. The Grade Crossing circuit provides prototypical o
Click here to download the full size of the above Circuit.
peration of the signals at level railway crossings and can supply up to 100 milliamps for LED flashers, small incandescent lights or other circuits such as crossing gates or sound units. The circuitboard has been designed to be easy to build and install. Widely available and inexpensive components are used in its construction. None of the parts are static sensitive. An upgraded version of the 2004 circuit is at this link - 2008 - Automatic Railway Grade Crossing Circuit. The new circuit designed to prototypically control crossing gates. The following diagrams show how the circuit is connected for a crossing with 1 track. A diagram of the circuit board showing the terminal block positions is used. The next diagram shows how the phototransistor sensors are placed along the track and the actions that occur as each is covered by the train. The sensors that start the flashers can be placed any distance from crossing desired. The signals will remain ON until approximately two seconds after the last car has passed completely through the crossing, uncovering both of the "STOP" sensors. As the train leaves the protected section of track, the "DISABLE" sensors prevent the flashers from being turned ON again by deactivating the "START" sensors. The circuit is ready for the next train in either direction approximately five seconds after the "DISABLE" sensors are uncovered. If the departing train is still covering a "START" sensor after...
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: