The Spectrum Analyzer is used for signal observation of the communications system in the frequency domain. It is a frequency selective instrument that allows the power level of each frequency component of a signal to be displayed on a regular oscilloscope: a dual trace oscilloscope or a single trace oscilloscope with an external sweep input having a sensitivity of 1 V/div. is required. The Spectrum Analyzer has two selectable input frequency ranges: dc to 30 MHz, and 85 to 115 MHz.  The center frequency is indicated on a 3½ digit display. The Spectrum Analyzer has an output for use with the optional Dual Trace Oscilloscope, Model 797, or the X-Y Recorder, Model 9492.

Two digital memories of 1024 horizontal points by 256 vertical levels provide a stable display at a refresh rate of 30 Hz. The frequency span is switch-selectable in five ranges from 2 kHz to 1 MHz per volt. With the oscilloscope set at 1 V/div., total spans of 20 kHz to 10 MHz are possible.

The bandwidth resolution is automatically optimized between 100 Hz and 50 kHz. Inputs to the spectrum analyzer may be attenuated by 40 dB in five steps. The input impedance is switch-selectable between 50 Ω and 11 MΩ. The input signal may be displayed in linear or logarithmic form (10 dB/V) up to a maximum display range of 60 dB.

The module is fully protected against short circuits and misconnections. Students use the instruments to make measurements in laboratory experiments performed on AM, FM, and digital communications systems.

• Specifications
•  
• Power Requirements: +25 V 750 mA / +11 V 600 mA / -25 V 475 mA
• Input Frequency Range: 0-30 MHz (500 Hz minimum) and 85-115 MHz
• Input Impedance: 50 Ω or 1 MΩ
• Input Signal Level: -70 to +30 dBm (50 Ω input)
• Maximum Input Signal Levels: 7 V (peak AC + DC) at 50 Ω impedance / 15 V (peak AC + DC) at 1 MΩ impedance
• Frequency span: (Oscilloscope/Plotter at 1 V/div.) 0 Hz; 2, 10, 50, 200 kHz; 1 MHz/div.
• Resolution Bandwidth: (3 dB) 100, 500 Hz; 2, 20, 50 kHz (automatic selection)
• Frequency Markers: 10, 100 kHz; 1, 10 MHz
• Marker Frequency Stability: ±0.003 %/°C
• Frequency Measurement Resolution: 1 kHz (using 10 kHz markers)
• Dynamic Range (input signal measurements: 60 dB
• Selectivity (60 dB/3 dB): Better than 13:1
• Output Display: External oscilloscope set the X-Y mode at 1 V/div. and/or X-Y (oscilloscope and plotter not supplied)
• Output Mode: HOLD/LIVE
• Output Scale Linear or Log: (10 dB/V)
• Output Level: Variable up to 10 dB from CAL position
• Memories (A and B:) 1024 vertical points x 256 horizontal levels
• Oscilloscope Outputs: X: 0 to 10 V; Y: 0 to 6 V
• Plotter Outputs: X: 0 to 10 V; Y: 0 to 6 V; ground
• Input/Output Signal Connectors: BNC (except plotter output, which is 2 mm banana jacks)

Physical Characteristics
Dimensions (H x W x D) 162 x 330 x 315 mm (6.4 x 13 x 12.4 in)
Net Weight 5.6 kg (12.3 lb)