Double conversion frequency synthesizer circuit diagram

The monocrystalline transceiver system uses a 10.240MHz reference frequency, which is added to the VC0 frequency to produce the transmit frequency. The same 10.240MHz reference frequency is mixed with the first IF signal to produce a 455kHz second IF signal . Dividing the reference by 2 provides a 5.120MHz signal, coupled to a 3x buffer whose output is adjusted to the third harmonic (15.360 MHz).