For reduction of power consumption and increase in efficiency with 1,4 to 28 percent, in a collector chain resistance we replace with a throttle which resistance in the working range of frequencies much more, than the general resistance of loading.
The size of inductance of a throttle gets out so that the variable component of current was not grounded via the power supply, and the size of blocking capacity – so that the collector of the VT1 transistor on alternating current was grounded.
Also in the amplifier there is a Council of Federation, its role not to pass a variable component on the power supply. Calculation is made to similarly blocking capacities, a difference only in that that in a formula (instead of Re Rf is put. Proceeding from it, we will receive the following values:
Usual process of production of a compact disk consists of several stages. As a rule, they include the following operations: preparation of information for record on a master disk (the first sample), production of the master disk and matrixes (a negative a master disk, replication of compact disks. The coded information is placed on a master disk by a laser beam which creates the microscopic hollows divided by flat sites on its surface. Digital information is provided by alternation of hollows (nonreflecting spots) and the islands reflecting light here. Copies of a negative of a master disk (matrix) are used for pressing of compact disks. Let's note that the hollows created by a laser beam are very small by the size. About 30-40 hollows correspond to thickness of a human hair, and these are about 50 microns.
Using formulas (1, (1, (1, (1, (1, (1, and the characteristic of the transistor provided in point 2, we will be convinced that the chosen resistance of feedback will provide the demanded strengthening coefficient on the necessary strip of frequencies:
As it was noted above as the output cascade we will use the cascade with parallel negative feedback on tension possessing the greatest shirokopolosnost, during the work on capacitor loading.
While all magnetic disks rotate with constant number of revolutions per minute, that is with an invariable angular speed (CAV, Constant Angular Velocity), the compact disk rotates usually with a variable angular speed to provide constant linear speed when reading (CLV, Constant Linear Velocity). Thus, reading internal a hundred-ditch is carried out with increased, and external - with the reduced number of turns. It causes rather low speed of access to data for compact disks in comparison, for example, with winchesters.