PC parallel port Null Printer Adapter
Posted on Nov 20, 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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This must be the most efficient bipolar transistor motor driver design for this application and I...
An AC triggered switch for low frequency signals. This is a basic ac voltage operated switch made...
A full range power controller suitable for lamp dimming and similar applications operate from a...
The circuit has a frequency response that ranges from 100 Hz to 3 MHz; the gain is about 30 dB....
This LM723 variable power supply circuit design is a very simple variable power supply that will...
Each step will result in a self functional unit. In the end of this journey, you will be able to...
This device is a simple timer, allowing to keep on the headlights of your vehicle for about 1min....
Given below, is a very simple circuit that can be used for charging car batteries. In this...
NJM2268 is a dual Video 6dB Amplifier with 75 drivers for S-VHS VCRsHI-BAND VCRsetc. One channel...
The schematic is this fairly simple transistor circuit: Seeing schematics with transistors in...
The circuit is based on the PIC 16F877 microcontroller, see schematic in figure 4. The digital...
When a network needs to transfer small blocks of information over long distances, RS-485 is often...
This is a rather old project I`ve done around 2005 but was not published on my website until now....
Shown for the XTR105 reverse voltage and over-voltage surge protection circuit. Zener diode is...
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