The GDK-1 (GPS Designer Kit) is an easy-to-use, plug-&-play designer kit. It helps designers deliver fast, low-cost, and integrated GPS timing clock solutions at 30% less than conventional timing module/board cost, while focusing on their core expertise. It comes with a GPS receiver, antenna and related cable accessories, and a smart GPS-disciplined SRO-100 Rubidium or SXO-75 double oven Crystal SynClock+®. The GPS can be from any vendor such as Navman, Trimble, Motorola, U-Blox, and Novatel thanks to the SRO/SXO's integrated multi-vendor SmarTiming+® interface.  The SmarTiming+ technology also filters and disciplines any type of input reference such as GPS, Cesium, Maser, and E1/T1 auto-adaptively at leading-edge 1ns resolution, while modeling the stability-affecting temperature range of the SRO/SXO at 0.1ºC resolution.  The designer kit comes with a Windows iSync+® software application to control and monitor a complete suite of time and frequency features as well as timing and holdover performance.  The SRO/SXO also has an integrated memory for seamless upgrades and performance/feature enhancements.