8 Channel LPT relay board
Posted on Jul 11, 2012
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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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The 4046 PPL is used as the heart of a tunable ultrasonic receiver that can be used to locate...
Transistors T1 and T2 form the mic preamplifier. Resistor R1 gives the required bias for the mic...
The electronic device feel the proximity which measures the user fast. But the distance that most...
The differential outputs are balanced and are designed to drive long lengths of coaxial cable,...
Two KOSS A-1220 headphone amps. Each share the same model number, yet have completely different...
Here`s something that might intrigue you Crystal Radio builders out there: A one-transistor...
National Semiconductor has been producing and designing ICs for use in switch-mode power supplies...
This circuit will drive a relay coil from a low power output, usually from an IC like 555 or a...
What do you do with those old 2-Meter FM rigs that don`t have any CTCSS tone capability Well, you...
As shown, this circuit can automatically adjust the brightness according to ambient light...
Figure 2 foot emitting a flashing light switch circuit indication. when s is closed, normal light...
Many times for various reasons we forget or can not water the plants that we have in our homes....
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