SU489194A1 - Harmonic signal generator - Google Patents

Description

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The invention relates to radio engineering and can be used in measuring equipment.

Known generator harmonic sig Nalov, containing a differential amplifier on transistors with a generator then; as in their common emitter circuit on a transistor of the same conductivity type, an inverting cascade.

However, the known generator does not provide a change in the frequency of the oscillations generated in proportion to the difference of the two control voltages, and also has insufficient sensitivity and has a complex structure.

The aim of the invention is to change the frequency of colibrations generated in proportion to the difference between the two control voltages, increase sensitivity and simplify the device.

To do this, the first capacitor, the resistor in the collector circuit of one of the differential amplifier transistors, are bridged by the second capacitor between collectors of transistors of the differential amplifier, the inverting cascade is connected to the junction point of the capacitors through the VO series and the emitter of the current generator transistor through the series a chain of consecutively connected nonlinear elements and a coider, connected by a base to the output of the inverting cascade.

The drawing shows a circuit diagram of the device.

The harmonic signal generator contains a differential amplifier on transistors 1, 2 with a current generator on transistor 3 in their emitter circuit and an inverting cascade on transistor 4.

Between the collectors of transistors 1, 2, a capacitor 5 is connected, a resistor 6 in the collector circuit of transistor 2 is set to: capacitor 7. The inverter is connected to the transistor 4;

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to the emitter of the transistor 3 of the current generator through the subsequently connected non-linear element 10 and the capacitor 11. The base of the transistor 3 is connected to the collector of the transistor 4 of the inverted cascade.

The harmonic generator of the 1st signal works as follows

The resistor 12, 6, 8 and the connectors 5, 7, 9 form a frequency-positive circuit of positive feedback.

It is natural that the output frequency of the sapnale, generated by the -ttjx generator, depends on the anryzhes on the base of transistor 2. An increase in this voltage causes a decrease in the frequency of the signal. The transform characteristic is determined with circuit stability, feedback and stability of the differential amplifier, which depends on the identity of the transistors 1, 2.

When the switches are turned on transistors 1, 2, the scatter and drift of the values of their parameters are partially compensated.

The H & d mode stability, as well as the levels of the compared voltages applied to the bases of transistors 1, 2, do not affect the output characteristic of the generator. By selecting the ratio of the elements of the feedback circuit MOJ71O, we obtain high sensitivity944

generator capacity, i.e. high steepness of the conversion characteristic of the generator. By changing the input voltage difference by –25 mV, a tenfold frequency change can be obtained4

Claims (1)

Invention Formula A harmonic signal generator containing a differential: a transistor amplifier with a current generator in their common emitter circuit for transient conductivity, inverted to the same, so that, in order to change the frequency of The oscillations are proportional to the difference between the two components of the sensitivity and simplification of the device, the first capacitor, a resistor and a collector circuit of one of the transistors are differentially connected between the collectors of the differential amplifier transistors of the amplifier of the second capacitor is bridged, the inverting input of the cascade connected S to the connection point of capacitors through a serial ShZ-circuit and to the emitter of the current generator transistor through a chain of sequentially connecting non-linear element and a capacitor connected by a base to the output of the inverting stage.