Reduction of poverkhostny and volume resistance leads to shunting of elements, emergence of galvanic communications between them, to increase of losses in condensers and transformers, to falling of good quality of coils and so on. All this causes deterioration of operation of the device and in a row a case its exit out of operation because of electric breakdowns.
As the foil used for foiling of the dielectric basis it is possible to use a copper, aluminum or nickel foil. However, aluminum foil concedes copper because of bad solderability, and nickel - because of high cost. Therefore as a foil we choose copper.
As in this academic year project the two-sided printed-circuit board is made, it is necessary to stipulate that the number of the conductors located from installation of radioelements needs whenever possible to be reduced. That is the main drawing of the scheme has to be from a reverse side of the printed-circuit board.
At this scheme there are two powerful output transistors it are required to which additional heat removal. Not to take a place on the printed-circuit board, we will not install additional heat sinks for these transistors. As the general heat sink the metal case of a casing will be used. These transistors through mica laying are installed on a back wall of a casing, and then by homutka and M3 screws are fixed on it. Mica laying is necessary in order that there was no electric contact between collectors of transistors.
Optimum to place the heatallocating and thermosensitive elements the designer has to be informed on a design of all equipment in general, including on the applied way of cooling (convection, compulsory air cooling and so Dahl and a way of installation of a payment in the equipment (vertical, horizontally.