A single IC provides all amplifiers: 74HC04 Hex Inverter ( a digital element). The 2nd oscillator synchronizes to 3 times the 1st oscillator and therefore the FM deviation is tripled. Using the lower freq f1 oscillator also enhances frequency stability.
In use at N6RE, Ray.
The 74AC14 Hex Inverter IC will work as an overtone crystal oscillator to > 110 MHz. Connect as shown below!
Many odd harmonic frequencies are possible X3, X5, X7, X9, X11. The multiplied output frequency does not necessarily equal an even multiple of the marked frequency. ATV crystals at 106 and 108 MHz oscillate at their marked values. A 10 MHz XTAL produced 110 MHz.
I do not have a 48 MHz crystal to try for a third harmonic 144 MHz oscillation. Perhaps you do....try it!
Ray, N6RE
P.S. What to do with the 5 remaining stages?
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