If you’ve already put a couple of solar panels on your balcony and gotten used to the fridge and laptop running on “free” sunshine during the day — congratulations, you’re halfway to real autonomy. But at some point almost everyone hits the same ceiling: a standard 3–5 kW inverter handles lights, phone charging, and the Read more…
The welding apparatus I built is a modernized version of a device that has proven itself well in practice; its description and sketches were published in the magazine Modelist-Konstruktor No. 3, 1966. The main point is that the new “welder” is significantly more powerful than its predecessor, and simpler to build and operate. Without any Read more…
Research by scientists and beekeepers’ experience show that with adequate quality feed and careful management, flying honey producers tolerate wintering well even in severe frost. For a weakened bee colony in cold weather, the trouble is less the low temperature than high humidity, when frames and the inner surfaces of hives grow mold, and the Read more…
Summer vacation time is approaching. To the numerous concerns related to preparing for the upcoming vacation, aquarium owners have one more: how to provide everything necessary for the underwater inhabitants during the owner’s absence. If you have no one to entrust your aquarium to, entrust its care to an automaton (Fig. 1) and rest peacefully. Read more…
The simplest electrical devices that our magazine offered to beginners work from a 3336L battery for a pocket flashlight. But it cannot provide much energy: after several hours of continuous operation, the battery “runs down”, and then it needs to be replaced. It is much more convenient to power homemade devices from a constant source 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…
