Transistor Improves Common-Mode Rejection In Difference Amplifier.

The comparatively low collector to emitter voltage ratings of transistors limit their maximum output voltage swing.

Examination of the two lower diagrams will disclose two types of recommended power supplies with which to operate the equipment. The one at the left has been in successful use for many years, and is to be highly recommended.

Reputable vibrator manufacturers work closely with their customers in regard to the checking of constants for new applications and to the checking of specifications and prints.

The vibrator acts as a full-wave interrupter into the usual transformer primary. However, instead of serving as a full-wave rectifier as is usual, the rectifier portion acts as two half-wave rectifiers.

The following circuit diagrams are presented to illustrate a few used in various vibrator power supply applications. The base is so constructed and wired that it can be inserted into its matching socket in two positions 180 degrees apart.

Considering first the primary circuit, it will be noted that shown as dashed lines are two resistors connected from each interrupter contact pin on the socket to the reed, or ground, terminal.

Still another factor that indirectly affects the choice of primary wire size is the fact that, at least for the usual 6-volt application, the number of layers of wire available for the primary winding is limited to three, or in a few cases four, for the wire diameters normally required.

The procedure for the design of vibrator transformers will require reference to the general information of the preceding chapters and especially to the graphs and data sheets in Chapter VII.

In the preceding chapters, it has been explained that the design of vibrator transformers differs considerably from that of small AC transformers.