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.

The discussions in the previous chapters have been limited to the three primary components of the vibrator power supply system and to the influencing factors of the applications in which a majority of the vibrators are used.

Perhaps it should be pointed out at this point that when using the primary timing capacitor the wave-form will have one additional characteristic not illustrated.

Typical curves are included in this text for the purpose of providing reliable technical information for use in making calculations.

The transformer core steel most often used in vibrator transformers are limited to four grades. These grades are usually designated by their specified core-loss characteristics as expressed in watts-per-pound, at a flux-density of 10,000 Gauss and 60 cycles-per-second frequency.

In order to stabilize the circuit and suppress this spurious oscillation, a resistor is placed in series with the secondary timing capacitor. The value of this resistor must be such that the critical damping resistance of the unwanted LC circuit is exceeded, while the critical damping resistance of the desired LC circuit is not reached.

The vibrator starting characteristics are quite important to the transformer but are often neglected. A serious transient condition may be imposed on the transformer by the vibrator during the first few cycles until the full operating frequency of the vibrator is attained.

The transformer used in a vibrator power supply is a very important and critical component. As one of the three principal components (the other two being the vibrator and the timing capacitor), its design and performance can control the resultant vibrator performance.

The selection of the most suitable vibrator can be made with relative ease. Most of the factors which govern this choice are controllable or are known at the beginning of the design work.

Time intervals "ti" and "t3," as before, represent the contact-closure time for the interrupter portion of the vibrator.

All of the previous discussion has been with regard to "Standard Frequency" vibrators, whose nominal frequencies are 115 cycles per second.

Many direct and indirect factors have an important bearing on the overall design of the power supply system and to the selection of the most suitable type of vibrator in particular.

From the above calculations and characteristics, it will be noted that the estimated input current at 2.0 volts CT, is well within the maximum value allowable for reasonable life expectancy.

The shunt-coil system employs a simplified mechanism as compared to the separate-driver system, for it requires fewer parts and adjustments.

The interrupter type of unit, as the name implies, interrupts the input battery current and switches it to the proper transformer windings so as to produce the desired alternating magnetic flux in the transformer core.

Vibrator power supply design - Development of Basic Transformer

The timing capacitor, or "buffer" capacitor, is the third important element to be considered in designing a vibrator power supply.

Vibrator Power Supply Systems have been used for many years to obtain high voltage currents from low voltage direct current sources. This text concerns the underlying principles of Vibrator Power Supply Systems and their application problems.