MODEL 907 The Model 907 Signal Generator is a lightweight, compact source of RF signals. The 7 to 11 GHz frequency range is continuously variable with front panel or external voltage control; frequency is displayed on a 31/2 digit LCD. Output level is continuously adjustable from 0 to -127 dBm by front panel or external voltage control; a 3Vz digit LCD displays the level. Modes of operation include CW, AM, FM and Pulse with internal or external modulation and trigger signals. In addition to the main RF output, there is a constant level auxiliary output. Two sync outputs and two monitor outputs allow timing and monitoring of modulation and triggering functions. 1.2 SPECIFICATIONS 1.2.1 Versatility The Mode! 907 Signal Generator is a signal source with AM, FM, pulse modulation and external sweep capabilities. All parameters are Independently adjustable. Pulse and FM modulation signals may be externally provided or selected from the Internal modulation generator. Frequency and output level may also be externally (remotely) controllable. External 0 to -I- 5V ramp with repetition rates to 15 Hz will sweep the entire RF frequency range. Internal modulator signals are available for monitoring and system synchronization. Modes CW: Continuous RF output. Frequency and level adjustable. FM: Internal or external signals can frequency modulate the RF output. Rate and deviation are adjustable. Pulse: internal or external signals can pulse modulate the RF output. Pulse width adjustable or fixed 50% duty cycle; rate and delay adjustable. External pulse mode can trigger the pulse circuits on rising or falling edge of input signal. A gate mode allows the external input to control pulse width. 1.2.2 Output NOTE Output specifications applicable to nonswept operation only. Frequency Varied by a 10-turn potentiometer and a ± 4 MHz vernier or by an external 0 to + 5V. Range: 7.0 to 11.0 GHz. Readout: 3 1/2 digit LCD, 10 MHz resolution. Accuracy: ±1%of reading. Stability: 60 ppm/°C; less than 20 ppm (± 10% line variation). Signal Purity (Internal frequency control, CW). Residual FM: <15 kHz peak. Harmonics: < -30 dBc Spurious: < ~ 55 dBc Level Varied by a 10-turn potentiometer or external 0 to + 13.6V (-10 dB/V). Output can be switched on and off. Range (Leveled): 0 to -127 dBm; 0.225V to 0.100pN (into 50Ω). Maximum Output: > + 3 dBm unleveled. Readout: 3 1/" digit LCD, calibrated in dBref, dBm and Vrms. Resolution: 0.1 dB. Amplitude Accuracy: Accuracy Output Level ±1dB 0 dBm ±2 dB 0 to — 60 dBm ±3dB -60 to -127 dBm Below -127 dBm power decreases monotonically, but is uncalibrated. Output level is continuously adjustable. Impedance: 50Ω. VSWR: <1.5 Connector: Female type N coax. Auxiliary Output Power: > - 5 dBm CW signal. Reverse power protection: + 30 dBm average. 1.2.3 Pulse Modulation Transition Times: <35 ns for leading and trailing edges; typically 12 ns/25 ns, respectively. On-Off Ratio: > 80 dB when main output is set at 0 dBm. Width: 200 ns to 100 (is in 2 ranges: for greater widths, use external gated mode. Delay Range: 3 to 1 ms in 2 ranges, relative to normal sync. (Not applicable to gate mode.) Internal Mode: Fixed square wave or variable width pulses; 10 Hz to 10 kHz in 3 ranges. External Pulse Mode: Triggers internally generated pulse delay and width from PULSE TRIG Input. PULSE TRIG Input: 1 Vp-p minimum trigger; slope and trigger point adjustable; ±10V maximum. External Gate Mode: RF output occurs for the duration that PULSE TRIG INPUT signal exceeds trigger level setting. 1.2.4 FM ■ Frequency Modulation Maximum RF Output Deviation: >5 MHz p-p. Internal Sawtooth Modulator: 10 Hz to 10 kHz in 3 ranges. External FM Input: >1 MHz/V; ± 2.5V max level; 0 to >10 kHz; 10 kΩ input impedance. 1.2.5 AM • Amplitude Modulation Ext. Modulation Frequency Range: 0 to 10 kHz. Maximum Source Level: ± 2V peak. Input Impedance: 10 kΩ. Sensitivity: 27 dB/V (nominal). 1.2.6 Modulator Outputs FM: Signal from external or internal modulation generator. 6000 source impedance. Pulse: Positive TTL level pulse occurring at selected repetition rate, pulse delay and pulse width of modulator pulse. Normal Sync: Positive TTL level pulse occurring at selected repetition rate. Delayed Sync: Positive TTL level pulse synchronous with modulator pulse with selected delay.