Posted on Oct 25, 2012

Two inverters, one resistor, and one capacitor are all that is required to make a HC(T)-based oscillator that gives reliable operation up to about 10 MHz. The use of two HC inverters produces a fairly symmetrical rectangular output signal. In the same circuit, HCT inverters give a duty factor of about 25%, rather than about 50%, since the toggle point of an HC and an HCT inverter is 1 /z Vee, and slightly less than 2 V, respectively.

Click here to download the full size of the above Circuit.

If the oscillator is to operate above 10 MHz, the resistor is replaced with a small inductor, as shown in Fig. 68-4B. The output frequency of the circuit in Fig. 684A is given as about 1/l.Brc, and can be made variable by connecting a 100-KO potentiometer in series with R. The solution adopted for the oscillator in Fig. 68-4B is even simpler: C is a 50-pF trimmer capacitor.

Leave Comment

characters left:

New Circuits



Popular Circuits

Switching Circuit
Doorbell Warning Switch
7MHz CW transceiver made with Motrola MC3362P
RF Probe Circuit
TB6600 5A Single Axis 5A CNC Stepper Driver For CNC Milling Machine DIY Max 50V
HOW TO make a cheap narrowband A/F gauge
Voltage-Doubler Circuit
Ultrasonic Reflectance Detector
Digital circuit strain with MAX1494
555 high performance photovoltaic street a control circuit diagram