It is not difficult to do even the novice hobbyist. And materials needed for this available.MICROPHONE OUT OF SCRAP MATERIALS
It is not difficult to do even the novice hobbyist. And materials needed for this available.Ham radio
It is not difficult to do even the novice hobbyist. And materials needed for this available.RIGHT OR LEFT?
Turn indicator, which are explained in this article is intended for motorcycle “Java”. The advantage of the self-made device before the industrial — low inertia: the scheme starts to work immediately after switching on the battery.THE SOLENOID
So, you are already familiar with the electromagnet, knows how to work the buzzer and electric bell (see “M-K” No. 8 this year). But there is a large group of Electromechanical devices, the main element of which is also an electromagnet. It’s the solenoid. That’s how they are.CALL, OPEN THE DOOR!
When apartment, Villa or house have two entrances, it is not always clear where to call. Electrosonic, which tells of the Bulgarian journal “Radio Television Electronics”, rid us of this inconvenience. When you press the button S2, relay K1 cambiocorsa their contact close. Simultaneously, lamp H2 lights up. Call H3 will beep until until the capacitor C1 is not charged up to the supply voltage. To signal again, the button S2 is released, and the capacitor C1 is discharged through the winding of the call. H2 lamp continues to burn as long as the supply circuit of the relay K1 will not open with button S3.GENERATOR “OF THE SEA”
Who has not experienced the beneficial effects of the measuring noise of the rain forests, the sea… the sound relaxes and soothes. That is why the simulator of the surf, which we offer to readers, is used as a stimulant of sleep in insomnia. Generator “of the sea” is easy to manufacture and configure, does not contain scarce radio parts and accessible even for novice radio Amateurs. Here’s how it works.SOUND AND LIGHT TEAM
Automatic devices that produce sound and light signals, are widely used in various designs and models. Usually auto-switch performs the multivibrator, the control of sound or light emitter (call, dynamic head, incandescent, etc.). These devices contain more transistors and a dozen resistors and capacitors.SIMPLE FREQUENCY COUNTER
A diagram of the frequency to control the frequencies in a relatively narrow range offers the magazine “Radio Fernsehen Elektronik” of the GDR. It contains all 7 elements. The device operates as follows. By using a series connected resistor R1 and Zener diode V1 of the input sinusoidal signal is converted into a rectangular amplitude Read more…
COMBINATION LOCK
About code locks wrote more than once. However, most of them are difficult to repeat. Design suggested by our Bulgarian friends (the journal “Radio Television Electronics”), devoid of this shortcoming. For opening this lock simply insert the key and complete the circuit with the resistor R1 a certain value (it is mounted in the housing of the key). If the resistance will be different from that specified on the schematic, the relay does not work and the lock will not unlock.NEW OLD COIL RUHMKORFF
Induction coil, in the last century invented Rumkorem, and is now used in experiments in physics. But now it is not fully satisfy the requirements of physical experiment creates interference, does not regulate the high voltage. consumes battery power, and feed the coil directly from the mains AC is impossible. We offer you to equip physical classrooms modernized version of the instrument developed on the basis of electronics.ROTATES FIELD
In a previous article under the heading “electronics for beginners” (see “M-K” № 8, 1979) we understand how magnetic field is formed it Turned out that, in particular, generates supplied to the coil (solenoid) electric current. The same field with a certain force acts on it carried to the magnet. But the magnet with the same force acts on the wire, which carries current. On the phenomenon of the interaction of electric current and magnet based electric motors (electric motors).