MEET DISCS

MEET: DISCSIn the old days, when required to perform switching in the electric circuits when the voltage rises to a certain threshold, resorted to the use of polarized electromagnetic relay. However, the substantial size and weight, lack of reliability of the kinematics and contact pairs severely limited the use of these devices. Now in their place came a miniature non-contact thingies called discs. This four-layer semiconductor diodes whose structure is like a two transistor: p-n-p and n-p-n type, with the base of one is connected to the collector of the second, forming the internal positive feedback (Fig. 1).

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THREE-PHASE — IN HOME NETWORK

THREE-PHASE — IN HOME NETWORK“For the treatment of infield has decided to replace the tiller internal combustion engine electric. Already got polutoraterabaytny the motor. But it is three phase. How to connect to the network, where only one phase and “my best”?
 
N. PARIN, Kursk oblast
 
“I heard that three-phase electric motors in the home network the homebrew use phase-shifting (but not electrolytic) capacitors of large capacitance. Is this true?
 
V. CHUPIKOV, Dnipropetrovsk

THE MACHINE-ECONOMY

AUTOMATIC-ECONOMYElectricity is steadily going up. So now even avid spenders are forced to take care of her savings, the benefit — there is a very wide selection of devices designed to save valuable kilowatt hours. Its rightful place is here and homemade machines off “extra” loads. It is gratifying that among the most interesting of them — the development receiving a “ticket to life” in the pages of “Modeller-designer” (see, for example, publications in № 4’89, 6’91, 9’92, 1’95, 7’2001 of the journal).

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CHIP REPLACEMENT ROM

REPLACEMENT OF ROM CIRCUITSAs a result of scientific-technical progress increases the degree of integration of integrated circuits (MS), including working in a permanent storage device (ROM). The developers of the micro-computer it is possible to use MS’s permanent memory with a larger capacity, thereby increasing the reliability of the computer while decreasing its size and power consumption. However, Amateur radio operators (especially in remote rural areas), this progress is often not happy. The reason is simple: cutting-edge MS from them or not at all, or they are, but beyond available to the programmer.

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THE SUITABILITY OF THE TUBE?

THE SUITABILITY OF THE TUBE?The durability of even the most modern electronic devices (EEW) is inferior to semiconductor counterparts. In most cases this is due to the emissivity of the cathode. The matter is further complicated by the fact that the diagnostic tool (commercially available instruments for measurement and control of emission current) is, unfortunately, very expensive, difficult to operate, as they contain a “naughty” anode and grid rectifiers, which are designed to create to check the lamp mode is close to the working. The received data are plotted, calculated certain characteristics, and by means of which required parameters.

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IMPORTED AND IMPROVE

AND IMPORTED PERFECTA commercially available power supply units are Chinese — made adapters have several advantages: they have an attractive modern design; dimensions distinguished by compactness; the scheme includes step adjustment of the output voltage based on the “razgovornoy” load; it is also important that there are acceptable for many price. However, they are not without, unfortunately, and specific disadvantage: during operation, they are “kicking”. Annoying piercing buzz with twice the mains frequency, particularly when using paired with a player or radio.

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AT THE END OF THE “NU, POGODI!”

REPAIR Electronic games with liquid crystals (especially “Nu, pogodi”) children love and appreciate. The disappearance of the “multisignal” a pair of WOLF-HARE “pocket” of the screen is perceived yet children sometimes worse than all misery. And who, if not us, adults (and even more so — consider themselves Amateurs with experience), not to please the younger generation quickly repaired electronic game.

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THE SOCKET WHERE THE BULB

SOCKET — WHERE IS THE LIGHTTo connect to network various electrical household appliances, machines in homes and apartments provided for the outlet. In the utility premises, outhouses and household buildings when posting back lighting outlet usually do not put. And this from the point of view of electrical and fire safety, in General, that’s right — there for them no supervision, there can be high humidity, etc., etc..

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