SU765982A1 - Rc-generator - Google Patents

Description

Hiccups close to sine are hiccups. far form. At frequencies other than the T-bridge tuning frequency, the negative feedback circuit's transmission coefficient is greater than the positive transmission coefficient of the chain. feedback, so the second and higher harmonic components are suppressed. The necessary phase correlations, i.e. the phase balance condition is fulfilled, since the positive feedback is real, the phase 10 shift of the transmission coefficient. The T-shaped bridge at the tuning frequency is equal to zero / and the operational amplifiers 1.6 and 7 in the operating frequency range introduce a slight phase shift, due to the 15 lrv limited flow band.

The generation frequency of the proposed HC-generator is defined by the expression 20, 1;, Г5 where tL. C, are the time constants of RC links 2 and 3; ) - resistance of resistors 8 and 9. The frequency stability factor characterizes the effect of additional phase shifts of the operating frequency amplifier 1 (due to the limited transmission bandwidth) on the relative non-stability of the frequency of the battles, at 9 it is equal to where / d - the gain factor national amplifier 1 without feedback. When T.-S, -: Sdl of coefficient K. we get from where it follows that in the proposed CS-generator era, the coefficient of stable frequency is 9 times greater than in RC prototype generator, the length of which is XCT- ,. The degree of suppression of the harmonic components is determined by the modulus of the return difference F, at the harmonic frequency:

At-Cdg TJ g With the degree of suppression of the second and third harmonics are equal, 2 and F, 1.6 L.

Since the prototype RC generator F., 15, and 22A ", in the proposed RC generator, the degree of second harmonic suppression is 8 times, and the third one is 7 times more than in the prototype. In the known devices, no optimization of the parameters of the elements of the circuit can achieve such results.

In addition, the proposed EjC generator has an increased amplitude stability.

The relative instability of the amplitude is determined by the expression

(TS

rfu

 3 Web "

FRAM. “T-lt where ffr o, -So-yk is the amplitude of the output voltage; resistances of resistors 4 T - transmission coefficient T-about of a different bridge at the tuning frequency (for the proposed RC-generator T 0, 001). Choosing 0.001 2G $ 0.001, you can get instability in the proposed PC-generator “GTD is much less than similar instability in the device prototype, and therefore, greater amplitude stability. The comparison is carried out with the same values of t, d and Ugtjm also with the same dependences JU - i. The proposed generator can use any of the known methods of automatic gain control. Thus, the proposed VS-generator has a frequency stability factor of 9 times more, the degree of second harmonic suppression is 8 times more, the third one is 7 times more than in the prototype, and also has an increased stability of 1PLITUDES. Taking into account that the proposed RC generator is fully assembled on a modern elemental base using operational amplifiers, the cost of which is constantly decreasing, a significant technical and economic effect can be obtained.

2 "- and

v- / / - / VD a n

where,

C: 2,3,4,5, ...

Claims (1)

1. IEEE Trans, on СТ-20, No. 4, 1973 p. 389 (prototype). one tm ± to IJ r- I ii 1 -d: