One section of the MC10101 is connected as a 100 MHz crystal oscillator with the crystal in series with the feedback loop. The LC tank circuit tunes the 100 MHz harmonic of the crystal and may be used to calibrate the circuit to the exact frequency. A second section of the MC10101 buffers the crystal oscillator and gives complementary 100 MHz signals. The frequency doubler consists of two MC10101 gates as phase shifters and two MC1662 NOR gates
For a 50% duty cycie at the output, the delay to the true and complement 100 MHz signals should be 90Â°. This may be built precisely with 2 ns delay lines for the 200 MHz output or approximated by the two MC10101 gates as shown.