SU426309A1 - BLOCKING GENERATOR - Google Patents

Description

one

The invention relates to radio engineering and can be used as a pulse generator.

A blocking generator is known, comprising a transistor, a pulse transformer, an emitter time, a driving capacitor, and a circuit for additional charging, a driving capacitor time.

This blocking generator generates pulses of limited duty cycle and low stability.

The purpose of the invention is to increase the duty cycle and increase the frequency stability of the generated pulses.

For this, in the proposed blocking-generator circuit for additional charging, the time of the driving capacitor consists of a thyristor, the anode of which is connected via a resistor to the emitter of the transistor, the cathode is connected to the power supply bus, the control electrode is connected to the collector of the transistor through a resistor.

FIG. 1 shows the basic electrical circuit of the proposed blocking generator; in fig. 2 - voltage diagrams at some points of the circuit.

The proposed blocking generator contains a transistor 1, a pulse transformer 2,

emitter time specifies a capacitor 3 and a circuit for additional charging of a capacitor 3, consisting of thyristor 4, the anode of which through a resistor 5 is connected to the emitter of transistor 1, the cathode is connected to the power supply bus 6, the control electrode is connected through a resistor 7 to the collector of transistor 1 In the blocking generator circuit, resistors 8 and 9, capacitor 10 and diode 11 are also used.

The blocking generator operates as follows.

At time i, transistor 1 is unlocked. Due to the positive feedback

through transformer 2, the normal blocking process begins, after which, at time tz, transistor 1 closes. At time ti, the capacitor 10 starts to charge. In case the duration of the blocking process is longer than the time for the thyristor 4 to go to the active state, the need for a capacitor 10 is no longer necessary. As soon as the thyristor 4 switches to the active region (time / h), the time setting capacitor 3

starts charging through a chain consisting of resistor 5 and thyristor 4. Capacitor 3 is charged until the current through the thyristor 4 at time / 4 becomes equal to the disconnect current. The voltage on the capacitor 3 at this moment is equal to the supply voltage. After disconnecting the thyristor 4, the capacitor 3 begins to discharge through the resistor 8 and the source 12 of the discharge current.

This blocking generator circuit is capable of generating pulses with a high duty cycle. The stability of the pulse repetition rate is achieved by charging the capacitor 3 before the supply voltage.

FIG. 2 the following notation is accepted: Ua - voltage on collector of transistor 1, t / b - voltage on capacitor 3, f / u - voltage on capacitor 10, / g - thyristor current 4.

Subject invention

A blocking generator containing a transistor, a pulse transformer, an emitter time specifying a capacitor, and a circuit for additional charging the time of the master capacitor, characterized in that with a view to increasing the duty cycle and increasing the frequency stability of the generated pulses, the circuit for additional charging the time of the master capacitor consists of a thyristor, the anode of which is connected to the emitter of the transistor through a resistor, the cathode to the power supply bus, the control electrode is connected to the collector of the transistor through a resistor.