For example: Agilent E4440A or Anritsu 68369
Tektronix Spectrum Analyzers
Tektronix 2754P
Programmable Spectrum Analyzer 10kHz to 21GHz expandable to 220GHz
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Manufacturer: Tektronix
Tektronix 2794
RF Spectrum Analyzer, 10 kHz to 21 GHz (325 w/optional mixers)
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Manufacturer: Tektronix
Tektronix 2794A
RF Spectrum Analyzer, 10 kHz to 21 GHz (325 w/optional mixers)
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Manufacturer: Tektronix
Tektronix H500
9 KHz - 6.2 GHz Real Time Spectrum Analyzer for signal interference analysis
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Manufacturer: Tektronix
Tektronix RSA5103A
Real Time Signal Analyzer 1 Hz-3 GHz 25 MHz Acquisition BW
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Manufacturer: Tektronix
Tektronix RSA5106A
Real Time Signal Analyzer 1 Hz-6.2 GHz 25 MHz Acquisition BW
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Manufacturer: Tektronix
Tektronix RSA6106A
Real Time Spectrum Analyzer; 9 kHz-6 GHz, 40 MHz Capture BW
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Manufacturer: Tektronix
Tektronix RSA6114A
REAL TIME SPECTRUM ANALYZER; 9 KHZ - 14 GHZ, 40 MHZ CAPTURE BW
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Manufacturer: Tektronix