In the sixth issue of our magazine in 1974 we told about the device “Pulse” for the control of knowledge of students. Practice operating the machine created by the participants NTTM Donetsk Polytechnic Institute, as well as the feedback from readers has convinced authors of the need to improve the design.TO INCREASE THE CHIP
Often aluminum wire suddenly breaks off, so even in the most remote places, leaving a short tail, what about twisting can not be considered. In these cases, rescue is simple, but effective way. You need the same wire is wound on a nail, whose diameter is slightly smaller than that of the chip, a few Read more…
Graceful and swift motorboat is an excellent educational model for aspiring shipbuilders. Work on bliss allows you to develop basic skills that will be required in the manufacture of sports cars of high class. With these boats, if they do, you can arrange competitions; it is only necessary to equip them with outboard electromotorically and to provide a place for mounting a battery from a pocket lantern.
In the last issue we talked about last representatives of cruisers with over 20 years of ex-one of the most important and revered ships in the fleets of all the major Maritime powers. The class that developed it seems to be quite natural and successful, but which is completely and permanently disappeared from the plans of shipbuilders in just two to three years.
10 years — 15 ago, the industry was widely released table lamps with fluorescent lamps, designed for a voltage of 127 V. A today 127 V network was preserved only in rare homes. It is clear that the owners of these lamps was now “tied” to expensive and bulky step-down transformers. We offer our readers we developed and tested a device that allows you to include a 127-volt lamp in the network a voltage of 220 V without the step-down transformer.
Futurologists from the technique, predicting the future of ground mass transport, a clear preference is given to the development of electric vehicles. However, until now, despite the efforts of scientists of several countries have not yet created a cheap, economical and quite powerful electrochemical generators. Modern lead acid batteries after more than a century of development almost completely exhausted its possibilities.
Sealed alkaline nucleotidase (NiCd) and Nickel-metallgidridnye (NiMH) batteries are finding increasing application not only in industrial devices but also in home appliances, replacing batteries size AA and AAA. But these batteries, like any other, eventually “emptied” and require charging. To recharge, as recommended by the instructions for use and marking of the batteries themselves, through them must pass through the current ICT = 0.1 mA from the numerical value of the nominal capacity C for 12 — 16 hours.
The design uses dynamic heads 0,25 GD or similar without any alterations. Ear cushions and pillows are made of a rubber sponge (you can buy in the pharmacy). For heads with a cone diameter of about 55 mm suitable sponge about the size of 155X60X35 mm. First take a piece of pressshpana or solid cardboard the size of 130X130 mm. In it cut a hole and glued it to the head (Fig. 1). Then, in the spongebob ear cushions cut out (or pluck) recess the speaker housing (Fig. 3), and the sponge-cushion (Fig. 2) make the hole oval. Its inner edge is cut from the side adjacent to the ear.