INVISIBLE WATCHMAN

INVISIBLE WATCHMAN

If a radio amateur’s inventory is burdened by a low-power portable radio station (or a set of two stations) designed for communication in the civilian range of 26.9 — 27.2 MHz, I propose a way to make good use of them. Often, a radio amateur is simultaneously a car owner and a dacha owner, who, Read more…

Portable Power Station

Portable Power Station

I propose a design for a gasoline-electric unit (GEU) “Firefly”, designed for charging batteries, powering lighting lamps and other DC consumers at 12 V. I developed this unit three years ago at the request of my friend, an avid hunter and fisherman. Since then, “Firefly” has been serving reliably, lighting his taiga cabin and helping Read more…

SENSITIVE METAL DETECTOR

SENSITIVE METAL DETECTOR

The metal detector I designed operates on the beat frequency principle, which arises from the difference in oscillations between the reference and the tunable oscillators (typically the 5th–10th harmonic, whichever is closest in frequency). This design allows the detector’s sensitivity to reach a level where it can detect, for example, a five-kopeck coin buried 10 Read more…

HOW TO AVOID THE “FLOOD”

HOW TO AVOID THE "FLOOD"

Many families today live in multi-storey buildings and use household washing machines. Anyone who has ever connected such a machine (to the electrical panel and plumbing system) knows how important both of these operations are. In particular, if the drain hose is poorly connected to the apartment’s fan pipes, a leak may occur. This can Read more…

Robot for painting on eggs

Robot for painting on eggs

Easter is just around the corner, which means it’s time to work miracles. And if you’re tired of regular paints, I’ll show you how to build a real robot artist that will paint on eggs! Meet Eggduino. This is a small but very smart machine that runs on Arduino and is controlled via Inkscape. With Read more…

YOUTH OLD GUITAR

Recently born, the guitar has managed to acquire its own history. At first it was a simple hybrid between a conventional housing with a wiring diagram. Then came the so-called “Board”: the whole guitar was a actually one exaggerated upper deck. “Board” has received the widest distribution in the world… and gradually disappointed many musicians.

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EMBED YOUR DIGITAL

BUILT ITS DIGITALUnfortunately, on vehicles of most episodes of “Zhiguli” are not put neither ammeters nor voltmeters, although sometimes there is an urgent need to monitor the battery condition. Produced by the same industry switches instrumentation is bulky and unsightly, and the price is commensurate with the price of parts developed by me homemade digital voltmeter that allows you to control the system voltage in the range of 10-16,3 V, accurate to 0.1 V.

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TECHPROGRAM RADIOPROTECAO

TECHPROGRAM RADIOPROTECAOPeople sometimes just have no time to twist knobs of the receiver to switch from one frequency to another. Here comes the advance settings of some of the most popular stations, pressed a button and listen to the desired program. In this mode you will be able to work any long-wave radio with a homemade console, designed for several fixed frequencies in the range of SV.

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