Nothing in this project is real original, but I did do a couple of modifications from the circuits I saw. The fellow that started this, as far as I can tell is Jack Bryant, KE4ID with his one tube superhet contest radio project. That was my basis for this set. I started drawing the circuit. I usually don`t release too many details early in a project but this time is different. I did
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get some good suggestions from my fellow radio friends, Ben Tongue and Mike Peebles. I had most of the design down but these two fine fellows gave me some extra ideas that were helpful in this design. This radio is built with the One Active Device (1AD) contest in mind. My two previous entries were done with two regenerative contest receivers. My 6SK7 and Acorn sets where the projects. They worked very well. But as time goes on, different ideas have to be tried. Jack and the others reported good results with these radios, especially when operated close to local stations. I don`t have that problem, but I just had to try it. The central part of this project is the 6BA7 vacuum tube. Using research of others, I decided that due the higher gain over other similar tubes, that this was the way to go. The other major section of this radio is the detector circuit. Looking closely, it looks like a fixed frequency crystal set. That`s what it is alright. The Bogen T725 provides a closer match between the detector diode / IF transformer and the headphones. An optional tap selector switch was added so that changing headphones would be easier. Better selectivity can be realized if you exchange the Bogen T725 for a transformer for an G berformer. The G berformer has an input impedance 5 times the Bogen and provides a much lighter load to the IF transformer secondary. The benny resistor (18k) will have to be changed to a higher value, about...
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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