The FSK003 is a high performance Space Ground Link Subsystem (SGLS) compatible AM/FSK Modulator command subcarrier generator. The module accepts ternary (1,0,S) data and clock inputs for Ternary Continuous Phase FSK/AM modulation.

Three outputs are provided. One output is adjustable from –30 to +10 dBm (50 Ohms). Two outputs are fixed level at 2 Vpp, nominal. All three outputs are ON/OFF selectable. The FSK003 is a single-slot width 6U x 160mm VME plug-in module.

A digital frequency synthesizer is utilized to produce SGLS tri-tone signal frequencies. Each FSK tone is accurate to 10 ppm (1 ppm optional). If selected, the FSK signal is amplitude modulated with a one-half data rate triangular wave. The AM Modulation Index is selectable from 0.33 to 1.00. The AM frequencies correspond to fixed command symbol rates of 1 kbps, 2 kbps, 10 kbps and 106 kbps. AM modulation is ON/OFF selectable.