The pre-multiplier stage multiplies the reference frequency by 3 to get to 1474.56 MHz. This frequency is sufficient to multiply up with the LMX1204 to 5898.24 MHz. The pre-multiplier stage uses a TRF37C75 RF amplifier operating in heavy saturation to generate high harmonic content. The amplifier is followed by a bandpass filter centered on the third harmonic to pass that signal to the LMX1204. The TRF37C75 normally operates at a 5-V supply, but for this approach, the supply is reduced to 3.6 V to reduce power consumption and increase the device saturation. After filtering, this approach yields a signal at 1474.56 MHz at about 0 dBm.