The article talks about an unusual musical device that can be assembled literally in one evening. This electric musical instrument is a kind of analogue of the original Thereminvox invented in 1920 by the Russian scientist and musician Lev Theremin, in fact, on his behalf, the device got its name.
Details and elements necessary to create a device:
microchip 555
speaker
audio output
-photocell
relay for adjusting sound volume
- breadboard pcb
Description of the principle of operation and creation of the device:
In the original Thereminvox model, a change in sound occurs due to a change in the capacitance of the oscillatory circuit. That is, it has two antennas that allow the musician to control the frequency and volume of the sound by changing the distance from the antennas to his hands, thus receiving various melodies. Therefore, to play the original Theremin model, you need to have a good ear for music, since the musician does not touch the instrument and cannot rely on any fixed positions, but relies only on hearing.
In fact, theremin can be called the first electric musical instrument. It is very versatile, suitable not only for the performance of various musical compositions, but can also be used to create sound effects like whistling, birdsong and others.
Model Theremin, which will be discussed in this article, has a simplified form. There are no antennas in this model, and instead of them a photocell is installed in the device circuit. Thus, by adjusting the brightness of the photocell, you can control to change the sound of the device.
It is difficult to call this device a real theremin, as it is greatly simplified, but still quite interesting. In addition, it is much easier to assemble such a musical toy on a photoresistor.
First you need to get all the necessary elements for the assembly of such a device. This Theremin consists of the simplest elements that you can buy in any radio store, or even get out of unnecessary old devices like Chinese tape recorders and the like. Although it is easier to buy, since all the elements used are quite cheap.
To make the assembly of the device, namely soldering, much easier and more convenient, the author also purchased a breadboard printed circuit board.
Thus, the longest and tedious process in assembling this device can be avoided: drawing and etching the tracks. In addition, this is a rather lengthy process and a ready-made breadboard will significantly accelerate the ability to build thereminvox.
When creating this device, the author relied on the diagram below, while simultaneously making small upgrades to improve the operation and appearance of the device.
During this modification, elements such as audio output, speaker volume control, as well as a device shutdown button were added to the device.
The 555th microcircuit was used as the basic element of the device.
Thus, the volume of the device changes due to the set control, and the pitch of the emitted sounds is modeled by a photoresistor due to a change in illumination. That is, with a movement of the hand, closing or opening up access to the photocell to the light, the tone is regulated and musical melodies are selected.
The whole device is powered by a standard battery like a crown.