The hardest part of the build was to find and / or design a circuit that could handle the load and still stay with in my budget. This little circuit does both. It varies the power output with one potentiometer (variable resistor) R1. R1 is a panel-mount pot with a shaft for a knob. It varies the power by synchronous triggering across the
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triac. On the triac TR1, terminal T1 is input, terminal T2 is output and G is the gate. All the parts were readily available form my local electronic supply store and built on a point to point prototype circuit board. This is a simple but a reliable circuit which will handle 15 Amps but in my unit it only has to about 4 Amps since I am controlling the primary windings of the transformer. On a side note, this circuit can be adapted to numerous other applications where controlling power is a requirement as in a lamp dimmer or putting a variable speed feature on an AC motor like a drill. As soon as SW1 is turned on, L1 and FAN1 come on. I wanted to do all the switching and control on the primary side of T1. Even though the voltage is higher (120VAC), the current would be much lower. The circuit is switching the incoming AC into the power control circuit thru relay RLY1. In turn, RLY1 is being controlled by SW2. The current draw of RLY1 is very small so this allows SW2 to be compact allowing mounting almost anywhere as in my pistol like soldering gun (carbon rod holder). I mounted SW2 in the trigger position eliminating the need for a foot switch. With my tweezer set up, the floor switch is still employed. L2 comes on with RLY1 and is mounted to the front panel. Voltage is fed from the power control circuit to T1. The highest current draw that the power control circuit with RLY1, FAN1 and T1 at full power is approximately 4...
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.....
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