The Spectratime LNRClok-1500 is a compact low-noise 10 MHz GPS/GNSS-disciplined Rubidium oscillator with an optional GNSS receiver. It delivers a sine wave output with phase noise of -145 dBc/Hz at a 1 kHz offset, has harmonics of less than -40 dBc, and spurious levels below -80 dBc. The oscillator achieves 1 ns resolution and provides time and frequency features. The optional GPS/GNSS receiver is the u-Blox 50-channel LEA-6T GPS with a 6-position engine and anti-jamming technology. It supports multi-navigational satellite system receivers, including GPS, Galileo, GLONASS, IRNSS, and BDS / COMPASS. The oscillator module measures 128 x 95 x 38.1 mm with SMA connectors, is compatible with the Stanford PRS10 model, and fits in a compact 1U chassis.