- 9101 Willtek Spectrum AnalyzerCondition: UsedFrequency: 4 GHz
- 9102 Willtek Spectrum AnalyzerCondition: UsedFrequency: 4 GHz
- 9105 Willtek Spectrum AnalyzerCondition: UsedFrequency: 4 GHz
- HSA9101B Willtek Spectrum AnalyzerCondition: UsedFrequency: 4 GHz