Hello,
I need a 12.6 MHz square wave signal for a video generator circuit. Now I know that a crystal oscillator would be recommended for this, but I'd like to test my existing circuitry before I purchase the final parts (I do not have any crystal oscillators).
I tried using a 4049 inverter (see attachment for configuration), and after removing the capacitor and lowering the value of R to the point just before oscillation stopped, I measured a frequency of 5 MHz with my oscilloscope. Is there any other type of circuit configuration that could give me a higher frequency? Or am I limited by switching speed of the CMOS chips themselves?
Thanks,
bob800
I need a 12.6 MHz square wave signal for a video generator circuit. Now I know that a crystal oscillator would be recommended for this, but I'd like to test my existing circuitry before I purchase the final parts (I do not have any crystal oscillators).
I tried using a 4049 inverter (see attachment for configuration), and after removing the capacitor and lowering the value of R to the point just before oscillation stopped, I measured a frequency of 5 MHz with my oscilloscope. Is there any other type of circuit configuration that could give me a higher frequency? Or am I limited by switching speed of the CMOS chips themselves?
Thanks,
bob800
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