The process of establishing electronic circuits the most exciting and interesting, but also the longest, sometimes bringing a lot of grief for Amateurs due to the lack of reliable power supply. After all, the battery or the battery do not serve indefinitely — they are discharged. Changes frequently and the line voltage. And each scheme is designed for a specific voltage. Changing it degrades the operation of the entire electronic device.
Without pretending to any special built in circuitry to use a more graceful version of an intercom that can be used as an intercom system in the private house or in the country. The design is simple and available for self-production, even a novice radio enthusiast. In standby mode the device does not consume battery power, but is always ready to work: just touch the button and — please say! Working on the second set you will certainly hear.
The voltage is from 1 to 12 In intervals of a single oxen allows to obtain a transformer, the circuit of which is shown in the figure. If desired, the switching is easy to implement dubplates switch. Constructive data of the transformer depends on the magnitude of the input current.
“What to replace the gauge?” — this question often arose during the meeting with an interesting measurement scheme. Ohmmeter, voltmeter, test transistors — these devices are difficult to imagine without a milliammeter. Nevertheless, this instrumentation can work without a dial indicator. This is easy to see, collecting scheme, in which the role of the indicator does… sound generator.
A lighter, a diagram is shown in the drawing, is intended for gas stoves. It is reliable, comfortable and safe. The device is a transistor blocking oscillator, powered by dry batteries with a voltage of SV.
The convenience of wireless remote control (RC) is undeniable. You can use them, without getting up, and the most interesting channel to enable, and the hardware on it to adjust according to the individual characteristics of perception.
Improvised medical vibroacoustic device “Vitafon” is intended for the treatment of bronchitis, sinusitis, tonsillitis, arthritis, ulcers, open wounds, fractures, bruises, hemorrhoids. Acting contact method (with continuously changing the sound frequency) at a particular organ, the apparatus excites mikrovibratsiyu affected (and adjacent to the nidus) of the tissues, activates the healing processes and recovery. A fundamental principle is the same therapeutic effect, as shown by the results of the research is a local increase in capillary blood flow and lymph flow due to reduction of hydrodynamic resistance of blood vessels within the area of vibro-acoustic influence of waves of a certain range.
Among the devices designed to destroy high-voltage discharge of mosquitoes, latausha the light bulbs, and relates my development. It does not contain scarce parts, assemble it under the force of even the novice hobbyist, and just a few hours.
For the guys from the club for young technicians Novosibirsk Akademgorodok has long been the rule: the work performed in the groups should be of a socially useful nature, contain elements of novelty and originality. When it was announced the competition “Young technology — agriculture”, butovtsy developed and produced for the collective farms and state farms the number of interesting devices. This measure humidity and temperature, automatic regulators, apparatus for determining the protein content in the wheat grains and the degree of oil contamination in the centrifuge of the tractor. Using an electronic thermometer, for example, it is convenient to measure the temperature of the grain, potatoes, soil. Guys the Steppe school Iskitim district of such thermometers are used for temperature control in potato storage.
The family of adapters, recently appeared a lot of new, specially designed for automatic recording of signals from the telephone line to the household VCR. Part of this apparatus includes, generally, a node of coordination of polarity and level of the input signal, and threshold-switching device.
