For example: Agilent E4440A or Anritsu 68369
Probes
Green Hills 070-PB350-02
Green Hills Probe 070-PB350-02 Multi-Processor Debug Interface w/ Accessories
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Manufacturer: Green Hills
Keysight / Agilent 1141A
HP Agilent 1141A Differential Probe, 200 MHz, 1:1 w/ Accessories
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Manufacturer: Keysight / Agilent
Keysight / Agilent 1142A
HP Agilent 1142A Probe Control and Power Module
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Manufacturer: Keysight / Agilent
Keysight / Agilent 42941A
42941A Impedance Probe Kit, 40 Hz to 110 MHz
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Manufacturer: Keysight / Agilent
Tektronix 6339A
Tektronix 6339A Buffered Passive Probe, 10 M?, 8 pF, 300 VRMS, 500 MHz
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Manufacturer: Tektronix
Boonton 952001B
RF Probe w/ 50 OHM Terminated BNC Adapter and 100:1 Voltage divider
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Manufacturer: Boonton