allows you to quickly verify the health of the quartz resonators. Diagram of the device consists of a generator (T1), detector (D1, D2) and DC amplifier (T2). By connecting the quartz to the two terminals of the generator, the power on. If the resonator is OK, resistor R2 appears to the high-frequency voltage which is then fed to diodes D1, D2 for detection. Highlighted in this case a constant component opens the transistor amplifier stage. Load UPT serve milliammeter ИП1 and lamp L1. The glow lamp indicates the functionality of the quartz. But his activity is judged by the readings of the milliammeter. For the active resonator current is 70-90 mA, and for inactive — 30-40 mA.
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A little patience, a little care and you’ll make a great airboat, which will obediently follow your commands on the water. In order to build it, you will need: a piece of plywood with a thickness of 2 mm, a few wooden sticks, a piece of tin from a tin can and a wire thickness of 1 mm.
The prototype of the computer mouse — a two-dimensional analog of the manipulator, connected to a personal computer (PC or PC) via the serial port corresponding to the RS-232 standard, and is equipped with a couple of buttons on a convenient and compact housing, is a device created almost 40 years ago at the Stanford research Institute and has incorporated a number of principles, authored by the famous inventor Douglas Engelbart (Douglas Engelbart). In appearance it is a wooden box with a “tail” — a communication cable. Obeying the movements of the operator’s hand, sneaking on the table on wheels, counting their speed and turns, this device is like sniffing the information that was immediately entered into the computer and controls the cursor movement on the screen. Indeed, what is not nosy mouse!..
City bus ZIS-155 production in 1949. The development and expansion of cities accompanied by the concentration of citizens in residential areas and, consequently, the factories in the industrial, has created the problem of passenger traffic, which could not solve a horse-drawn vehicle for personal use. And in the second half of the XIX century in cities there are predecessors of buses and trams, horse and steam-powered.
“After reading # 1, 1975 note”, Polihale”, I can not write about his former teacher, the head of the circle of technical creativity of the Chernyshev Lev Sergeyevich,” writes a reader from the village Krotovka Kuibyshev region, Liquor.
There is near Moscow, Serpukhov district, well-known vegetable farm “zaoksky”. Here, in high school, already DEA works student design bureaus, organized from the students of high schools teacher of Evgeny by Diligently. A quarter of a century he gave to the beloved work with children. Many of his pupils-modelers repeatedly took the first places of ka of the regional and national competitions were the winners of the all-Union competition; 12 masters of sports prepared them for this time. Experienced youth mentor bears the honorary title of honored coach of the RSFSR.
Music lovers understand the interest shown by people of different ages and professions to all new in the field of stereophony. The development of electronics and improvement on the basis of sound engineering techniques have enabled the lovers of house concerts to listen to gramophone records and tape recordings with a sound quality close to natural. Stereo replay system allows to obtain aesthetically the most complete and accurate representation of the executable composition, all the colors, the nuances that are sought to convey in a recording musicians.
Summer is a time of exciting tours for lovers of water tourism. However, it is not easy to reach the shore with a heavy backpack and kayak.
The idea is to make the car the most I had in those days, when “the Zhiguli””Muscovites” and even “the Cossacks” could be bought only after standing for many years in the queue. Then came other times, and the car ceased to be a deficit. There are so many makes and models, what to choose-that became difficult.
Carrier-based fighter F4U-5/7 CORSAIR. In the annals of aviation are not many aircraft left in her mark. But it is to such aircraft include the American fighter F4U CORSAIR the Chance Vought company, which had a great influence on the outcome of the air battles over the Pacific.
