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As Constructing a Simple Transmitter of A.M. voice

This transmitter is so simple to construct as the radius to crystal, was designed by Simon Quellen Field. The transmitter not only is easy to arm but it fits in the palm of the hand.
Beam Click in the photo for a greater image
Following the antenna, this transmitter can send its signal from a room to another one or in all the district. The first version took control of clips, but this uses some welds.


We will need these parts:


The oscillator is the heart of the transmitter. Patitas has four, but we will only use three of them. When one connects the batteries to two of patitas, the voltage in third patita jumps between 0 volts and 5 volts, million of times every second. The constructed oscillator this in a metal small box. The edges of the small box are cleared except the left corner. This indicates the place where patita is located that is not used. This simply serves to assure the oscillator in its place, but it is not connected nowhere within the small box. The other main part is the transformer of audio. In this circuit is used it as modulator. The modulator changes the force of the radio waveses to equal them to the volume of music or the voice that desamos to transmit. The diagram of the transmitter is seen down: The photo of the complete transmitter:
Beam click in the photo for a greater image
The transformer you can obtain it from a radius to transistors in disuse, this has two patitas in a side (red and green in the photo) and three patitas in the other side (blue, black and green in the photo). The side with the two patitas is the one that it has low impedance (the side of 8 ohms). The side with the three patitas is the one of high impedance (of 1000 ohms). The three means of patitas are called central APT, we will not use it in this cirucito.

As weapon

The transformer at heart has two metal legs that serve to hold it, but s elos can double for being able to glue to a base. The transformer is due to place to a flank of the base so that there is field for the oscillator. If we used a printed circuit, we must place it to the right, the copperplated part must be downwards. The oscillator also has patitas to hold it, introduces these in holes and doubles with care.


The transmitter is verified this way: It connects the plug of the headset in a sound source, as a radius to transistor, a headress CD, etc. The battery of 9 volts fits. You maintain the transmitter near a radius A.M., while you are moving the dial up to 1 000 and can excuchar the sound in the radius. It fits the gain controls. Without antenna and conección to earth the transmitter will be able to be listened to in a radius placed A.M. some centimeters, but with an antenna (copper cable) and a good conección to earth the transmitter will be able to transmit until several tens of meters.


The oscillator is connected to a long cable that for of antenna and have been communicating 9 volts to him of electricity alternatively and luego0 volts time and time again. At a speed of 1 million times per second. The electrical charge travels by the antenna, causing that emits radio waveses of the antenna. These radio waveses are caught by the receiving A.M., amplified and taken to the loudspeaker where they are turned into sound. Purchase of our CATALOGUE
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Questions a:

Miguel Vargas via