SU144201A1 - Device for automatic tuning of high frequency generator - Google Patents

Description

Devices for automatic frequency tuning of an electronic oscillator are known. However, they do not have a wide enough range of adjustment.

In the moments of non-switching of the division factor, frequency failures are possible due to the fact that the external influence is not synchronous with the frequency of the tunable oscillator. A.

The described devices eliminate these drawbacks.

The device for automatic frequency tuning contains a band frequency divider with a tunable division factor. The frequency divider is made in the form of two scaling blocks. One of the blocks has a constant conversion factor, the second - an electronically controlled conversion factor. The inputs of the scaling units are alternately connected to the output of a tunable generator. This makes it possible to spread the tuning range while maintaining a high frequency stability of the tunable oscillator.

In order that the change in the division ratio of the frequency divider does not lead to phase faults, the control pulse arrives at the conversion unit with a tunable division factor at the moment when the tunable generator is disconnected from it.

The block diagram of the device shown in the drawing.

The output of the tunable generator 1 is connected to a conversion unit 2 with a variable conversion factor or to a conversion unit 3 with a constant conversion factor through the electronic keys 4 and 5.

In the initial state, the key 4 is closed, the key 5 is open. When a pulse appears at the output of the counting unit 3, the trigger 6 overturns by closing the key 5 and opening the key 4.

No. 144201-2. From the output of counting unit 2, a pulse arrives at the comparison circuit 7 and at trigger 6, switching the ECP. The key 5 is opened, the key 4 is closed. Then the cycle of operation of counting blocks 3 to 2 is repeated. The comparison circuit 7 from the output of the counting unit 2 receives pulses of frequency

/.--/

 L / ,, - | -LL

where / 2 - frequency tunable generator;

NZ - conversion factor of conversion unit 2;

NZ - conversion factor of the conversion unit 5.

The frequency () is compared with the frequency supplied to the comparison circuit from the reference oscillator 8 through divider 9. If there is a frequency mismatch, a control signal is output to the oscillator /, which changes accordingly its frequency.

The impulse, which changes the conversion factor of the conversion unit 2, arrives at its control input from the conversion unit 10 via the key //. The key 11 is controlled by the trigger 12. When the signal arrives at input 13, the key is closed, when the signal arrives at input 14, the trigger 12 opens the key //.

The calculating unit 2 is executed so that one pulse, which comes through the switch 11, changes the conversion factor by the same value. The moment of arrival of the control pulse is determined by the conversion factor L / W of the conversion unit 10. is selected so that the control pulse arrives at block 2 at the time when this block is disconnected from the generator /, i.e. key 4 is closed. This eliminates the possibility of overruns and frequency failures.

The described device can be applied in systems where a smooth restructuring of a generator or a local oscillator is required.

Subject invention

Claims (2)

1.A device for automatic tuning of a high-frequency generator, containing an automatic frequency control system with a band frequency divider included in a tuning ring between a tunable generator and a generator frequency comparison circuit with a reference signal frequency, characterized in that in order to widen the tuning range and increase smoothness adjustment while maintaining a high frequency stability tunable generator, it as a band frequency divider applied recalculated bl OK with a constant conversion factor, and a unit with an electronically controlled conversion factor and switches, alternately connecting the inputs of these blocks to the output of a tunable generator and stopping the supply of a pulse commuting dividing factors of the counting unit when the generator is precisely tuned. 2. The device according to claim 1, characterized in that, in order to eliminate overruns and frequency failures caused by the asynchronous switching of the division factors, an additional recalculation unit connected between the output of the frequency divider and the key circuit was used for synchronous tuning of the division factor with oscillator frequency oscillations. through which the pulses governing the change of the division factor pass. /five