This page steps through each section of my implementation of BAMTRAT. Many of the component values shown were determined experimentally, to suit my own tastes and preferences. As when building an acoustic instrument, there is a lot of room for experimentation and customisation in electronic instruments generally, and theremins specifically. A note
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on capacitors: here`s an opportunity to use ceramic capacitors, especially the NPO variety. While ceramic caps are generally considered less than ideal for hi-fi audio, they`re terrific for RF; they tend to have less capacitance drift with temperature than most plastic types, and also have a vanishingly small "equivalent series inductance" as compared to capacitors wound with foil and film. This simple-yet-effective "Battery Eliminator" provides the required voltages (+80, +3 regulated and -7. 5) to operate BAMTRAT. It uses two transformers salvaged from 6v, 0. 3A "wall-wart" supplies to step the voltage down for the filament and C- supplies, and back up to supply the B+ voltage. The 6v AC output is follwave-rectified by the positive side of bridge D2-5, filtered by C15, and regulated by an adjustable regulator (LM317), providing regulated 3v for the series-parallel connected tube heaters. It`s a Really Good Idea to include six 1N4002 diodes as shown in blue, as protection in case one or more of the tubes are removed from their sockets; this will prevent voltage from ever exceeding about 1. 8 volts. The negative side of the bridge supplies the negative bias voltage for the power amp, filtered by C14. Since there`s very little current drawn from this supply, even the 47 µF shown is an overkill. The stepped-up B voltage is rectified by bridge D6-9, and two-stage filtered by C17, C13 and R10. Since the PA draws the most...
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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