Hits:900 Shortwave antenna
New solutions are not often appear in antenna technology. To them, without a doubt, proposed last year by Vladimir Polyakov an interesting variant of two-element directional antenna with...
Read moreHits:417 Power supplies
Widespread pulse DC-DC power supplies, due to their higher efficiency compared to linear. Although they concede less linear stability of the output voltage, but with a significant change of the...
Read moreHits:2446 Audio
The following diagram is Mesa Boogie dual rectifier solo head schematic diagram. This is a tubed pre-amp and tubed amplifier designed and manufactured by Mesa Boogie. The following schematic is...
Read moreHits:1165 Metal detectors
First of all I want to immediately dispel preconceived notions about a person with a metal detector, as the Defiler of graves or the "black Ranger", relation mafia weapons during...
Read moreHits:1305 Indicators, detectors
Ultrasounds around us everywhere, it can be "negotiations" animals noises of various equipment, as well as ultrasounds are specially generated the sounders, medical devices. Unlike the sounds of the audible...
Read moreHits:836 Power controllers, thermometers, heat
When growing seedlings and plants in greenhouses or on heated soil is important constantly to maintain temperature within specified limits. This function successfully performs automatic thermostat, electric contact is made...
Read moreHits:875 Antenna amplifiers
The results of the test amplifier SWA for Polish antennas. No. Model 50 MHz 230 MHz 470 MHz 800 MHz I ponv., mA The number of transistors Notes 1...
Read moreHits:558 Clocks, timers, relays, load switches
In the national economy is widely used equipment powered from three-phase network requiring observance of the phase sequence. Usually this is achieved the corresponding switching wires, but during various renovations...
Read moreHits:408 House, garden land, hobby
I activated electric water appear special properties: this moisture has a significant influence on the course of oxidation-reduction processes in animate and inanimate nature. Using water activated, enthusiasts achieve success...
Read moreHits:402 Audio
DescriptionAfter several requests by correspondents, the decision of designing a 9V powered Headphone Amplifier was finally taken. The main requirement was to power the circuit by means of a common...
Read moreHits:622 Bells and audio simulators
Sometimes you want to know: "is not called in the door when no one was home?". This will help offer a musical call that has a special memory function. Made...
Read moreHits:775 Television and video
Selectors, the principle of which is based on the synthesis frequency, called selectors PLL ("Phase Locked Loop", which translated to English means "closed loop PLL"). These selectors are also called...
Read moreHits:468 Power supplies
This automatic NiCd charger for 9V NiCd batteries is using 555 timer properties and is very easy to build. Why is an automatic 9 volts NiCd battery charger? Because you...
Read moreHits:593 Power supplies
Ham radio operators often offer their products in print or on circuit boards. In their manufacture have to drill a large number holes of small diameter (0.8... 1.2...
Read moreHits:665 Shortwave antenna
The problem of creating an effective antenna for the bands 160, 80 and 40 meters for working in confined spaces concern to many hams, including me. Previously used LW, Dipole...
Read moreHits:335 Lighting
One of the designers of the T-34 - Koshkin said that the most reliable detail - TA, which is not. Here and in the proposed semi-automatic machine for "eternal" lamp...
Read moreHits:1178 Audio
The proposed calculation method based on simple measurements performed with the well-defined instance of a loudspeaker mounted in bass reflex and acoustic on demograficheskim determining the size of the latter.In...
Read moreHits:397 Bells and audio simulators
Such a call can be set in the apartment instead of the usual electric. And then when you press the button at the front door of the apartment filled with...
Read moreHits:437 Power supplies
When you turn on power supplies amplifiers, laboratory and other BP occurs in the network interference caused by inrush currents transformers, the charge currents electrolytic capacitors...
Read moreHits:621 Power supplies
In the operation of laboratory power supplies often there is a need monitor the current consumed by the load. In most cases, with this purpose in the output...
Read moreHits:375 Power supplies
DescriptionAn increasing number of appliances draw a very small current from the power supply. If you need to design a mains powered device, you could generally choose between a linear...
Read moreHits:372 Other
For many years now, magnetic (or electromagnetic) water descaler devices have been showing up on the shelves of Home Improvement and other DIY stores all over Europe. Despite the numerous...
Read moreHits:1400 Radio transmitters
The radio microphone, schematic diagram of which is shown in Fig. 8. operates in the frequency range 65-108 MHz with wideband frequency modulation. This allows you to take the signal...
Read moreHits:481 Telefonie
As is known, to the territories covered with reliable cellular communication, abut areas where communication is not guaranteed. Usually this is because because of the terrain straight wave is very...
Read moreHits:576 Television and video
A schematic diagram of a transmitter placed in Fig.1.The transmitter operates in the UHF range (UHF) and is built on one chip and two microwave transistors. It ensures the perfect...
Read moreHits:688 Wireless microphones
There are radio repeatersthat allow you to not only listen to a phone conversation without the tube, but the conversation in the room where they are installed in the handset...
Read moreHits:1005 Power supplies
Modern portable computers, so-called, laptops, are popular. They are much more comfortable with their stationary counterparts. The laptop can be put in a bag and take with you, for example...
Read moreHits:792 Metal detectors
Encyclopedia of electronics and electrical engineering Free library / Schematic of electronic and electrical devicesMetal detectors category FD (Frequency Domain), theory Encyclopedia electronics and electrical engineering /...
Read moreHits:385 Clocks, timers, relays, load switches
The device is designed to automatically turn on a single electronic of the device when turning the other. The first one is called the slave, and the second - leading...
Read moreHits:382 House, garden land, hobby
This generator can be used in the storage of grain and other facilities for food storage. The oscillator circuit shown in the figure, consists of a low frequency modulator (C1...
Read moreHits:382 Indicators, detectors
It is not always immediately obvious whether a power-consuming appliance is switched on or not. Examples are the lamp in the attic or the shed, or electric heating in an...
Read moreHits:381 Clocks, timers, relays, load switches
The following scheme allows you to manage network load (220V) from of devices formed on the chip and having an output TTL level. Scheme has opto isolation, which allows a...
Read moreHits:927 Security devices and alarm
This autostorage in comparison with similar devices, published in the magazine "Radio" earlier, does not have any fundamental innovation. However, he interesting that assembled only three chips and four transistors...
Read moreHits:585 Audio
Long in the corner gathering dust domestic AC electronics 015 based on 75 HDH-1-4 and it disturbed (throw a pity). And the subwoofer in the car was not, however, then...
Read moreHits:345 Power supplies
A symmetrical ±5V power supply is often needed for small, battery-operated operational amplifier projects and analogue circuits. An IC that can easily be used for this purpose is the National...
Read moreHits:304 Clocks, timers, relays, load switches
Beeps 7.5 seconds after a preset timeAdjustable time settings: 15 sec. 30 sec. 1 min. 2 min. & othersCircuit diagramParts:R1 220R 1/4W ResistorR2 10M 1/4W ResistorR3 1M 1/4W ResistorR4 10K...
Read moreHits:504 Power supplies
Circuit diagram General Description and circuit operation:This is an efficient flyback driver for modern cylindrical rectified television flybacks. Many sites doesn't provide circuits driving these transformers, they simply say that...
Read moreHits:367 Lighting
Compact circuit, Can be wired in parallel to existing switchesThis device allows one or more lamps to illuminate at sunset and turn off at dawn.Q1 and Q2 form a trigger...
Read moreHits:362 Power supplies
Description In a lot of cases we needed a 220VAC voltage, in spaces where it does not exist, in order to we supply with power, various small appliances. In the...
Read moreHits:531 Audio
It has the following main technical characteristics: Rated output power....... 75 watts THD.......... 0,06% The bandwidth of.......... 20 ... 40 000 Hz The signal-to-noise.......... 86 dB The voltage........... ±40 In...
Read moreHits:490 Lighting
The proposed device allows using a conventional switch with one pair of contacts to control a chandelier with four lights, including one, two, three or all four.The first time after...
Read moreHits:1040 Ignition system
Know about the importance of setting optimum ignition of the combustible the mixture in the cylinders of a gasoline engine for maximum power, efficiency and proper temperature. The implementation of...
Read moreHits:639 Television aerials
When using the viewers several television antennas, receiving signals from different directions on different bands and channels you receive their loss-free transmission to the TV with the best quality. How...
Read moreHits:307 Other
A low resistance ( 0.25 - 4 ohm) continuity tester for checking soldered joints and connections. This simple circuit uses a 741 op-amp in differential mode as a continuity tester...
Read moreHits:556 Telefonie
Every year computer equipment all firmly embedded in our lives. Continuously multiplies the number of users of personal computers. In this regard the question arose: is it possible to expand...
Read moreHits:632 Indicators, detectors
Monitors battery voltage, Three-LED DisplayConnecting this circuit to the battery of your vehicle, you will always know at a glance the approximate voltage available. An indication of battery voltage is...
Read moreHits:581 Radio transmitters
The transmitter operates in the range of 65-73 MHz with frequency modulation. The range in the use of framework compact antenna is about 150 m. the Duration of operation of...
Read moreHits:523 Audio
The impact head direct radiation that is produced it sound pressure, as is known. proportional to the vibrational speed of the diffuser. The acceleration of the cone is proportional to...
Read moreHits:454 Power controllers, thermometers, heat
This controller differs from similar published the fact that it regulates (reduces) heat capacity of the soldering iron does not change its voltage supply and the interruption of the current...
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