One Advantage of these two units is the Sensor can be placed Away from the heater, therefore sensing the Actual Room temperature, not the direct heat from the heater. These can also be used in a confined space with a Heat Lamp, to create a Drying Oven. This First Circuit was designed by me to replace the Mechanical Thermal Switches used in some El
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ectric Heaters I have. The Electrical Contacts on these Mechanical Thermal Switches are getting pitted and are "No Longer Reliable". They could quite easily weld together, keeping this heater on Full. THAT IS DEFINATELY NOT GOOD! The Coarse Temperature Adjustment is a Trimpot on the Circuit Board, set to give a nominal range when using the Fine Adjust. The Fine Temperature Adjustment is a Standard Potentiometer with a Insulated Knob and/or Shaft to provide electrical protection against electric shock. Using this control you can set the harter to automatically turn "On and Off", Automatically Regulating the Room`s Temperature. The Power Control for the Triac should be a 2 Watt Potentiometer, Also with a Insulated Knob and/or Shaft to provide electrical protection against electric shock. Or it can be a 2 watt resistor on the circuit board, set for an appropriate heat level. "Typically Full On", as that would be the Normal setting, when using the Mechanical Contacts. On the Schematic, I show a 10 Meg Hysteresis Resistor. This may be made Lower or Higher depending on how many degrees difference you want between On and Off cycles. Values between 100 K-Ohms and 22 Meg-Ohms are acceptable. The Disadvantage of a Triac is you will Not get 100% Efficiency. This Second Circuit is Simular in design, but uses a Conventional Relay. This will effectively give the 100% Efficiency. Even though the Schematic shows a 2N3904, I used a 2SD401A....
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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