A field portable signal generator featuring direct RF synthesis from 10kHz to 1GHz and a full +13 to -133dBm output level range. The front panel features touch sensitive membrane type controls and includes LED displays of carrier frequency and carrier level or modulation rate and modulation level. An analogue meter is also included for displaying SINAD signal to noise ratios, the external modulation I/P level or the battery state when DC power is applied. Internal amplitude, frequency and phase modulation are provided, with provision for external modulation. Similar to Item 509 but with improved facilities, including a rotary control to enable adjustment of the selected parameter, programmable sequential tones for SELCALL systems and low distortion. 1kHz spot frequency for accurate modulation settings. GPIB Interface.