This document is a user guide for the GSM900 evaluation board for a PLL frequency synthesizer. The evaluation board is a self-contained board that includes the synthesizer, VCO, and loop filter for generating GSM frequencies. It is designed for a 20 kHz loop bandwidth and allows complete control of synthesizer functions from a PC using accompanying software. The board can be operated with either a 3V or 5V power supply and has typical phase noise performance of -91 dBc/Hz at 1 kHz offset and better than -90 dBc spurious performance at 200 kHz offset from the carrier.