Among self-defense devices, electroshock units (ESU) are far from the least notable, especially in terms of psychological impact on attackers. They are, however, quite costly, which motivates radio amateurs to build homemade analogues (see, for example, the detailed article on this in issue No. 5’99 of “Modelist-Konstruktor” magazine). Without claiming to be highly original or Read more…
Motion sensor DD-010 disassembled with the control board removed and an additional siren (100 dB sound level) type KPS-4510 connected. Motion sensors (DD) based on Fresnel lenses and pyroelectric detectors can be used not only for their intended purpose – to turn on lights or as an element of a security alarm installed indoors. Cars Read more…
A vehicle’s electrical system can be supplemented with a device whose schematic and wiring are within reach of even a beginner. This device is a controller whose value is clear: its status LEDs give constant, reliable information on the condition of the stop lamps, with minimal draw from the onboard supply. When the brake pedal Read more…
To avoid running extra wiring for auxiliary electrical appliances when using a portable lamp, it is enough to fit a homemade adapter into the lamp holder, as shown in the figure. To make the adapter, use a lighting socket in which three holes are drilled: one in the base—for the cleaned (glass and glue removed) Read more…
Portable electronic devices with low-voltage power supply are often designed for batteries and accumulators. Among such devices, the most popular are electromechanical and digital clocks, radio receivers, flashlights, and… wireless doorbells operating on a radio channel at a frequency of 303 MHz (there are variants at 933.25 MHz). Digital cameras with a connector for external Read more…
For remote monitoring of the serviceability of stop-light lamps in a car, transistor electronic («Modelist-Konstruktor» No. 6’2000) or relay-transistor devices are usually used. The latter is part of the standard electrical equipment of some cars as relay 4402.3747 and represents a design of magnetically controlled HERmetically sealed CONtacts — reed switches («Modelist-Konstruktor» No. 7’91, 4’98, Read more…
The metal detector I developed has not yet been used in peacekeeping operations to detect and neutralize minefields, nor in large-scale geological or archaeological surveys. Designed not for professionals, but for amateurs whose desire to “look underground” can be satisfied by a design with the parameters given in the table, it is an improved version Read more…
The importance of proper operation of a car’s electrical equipment is, of course, indisputable. This thematic selection prepared by our author tells how to increase its reliability. HOW TO MEASURE THE DWELL ANGLE? The dwell angle (contact closed angle) of a VAZ-2105 car can be determined by the amount of movement of the camshaft timing Read more…
When lighting fixtures and electricity were cheap, the question of a thrifty approach to choosing lighting for stairwells was not seriously considered by anyone. But life has taught everyone to count every penny, so there’s no need to convince anyone about the advisability of using an automatic stairwell and corridor lighting switch (ASCLS). The question Read more…
I’ve been familiar with the “Modelist-Konstruktor” magazine for more than a year now. Mainly as an avid reader and somewhat less as a DIY enthusiast, trying to implement in practice some of the promoted ideas and original technical solutions in the conditions of a simple home workshop. Now I’m offering one of my own developments. Read more…
