For example: Agilent E4440A or Anritsu 68369
Ovenized Oscillatrors
Keysight / Agilent 10811A
Ovenized Crystal Quartz Oscillator OSC 10MHZ
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Manufacturer: Keysight / Agilent
Keysight / Agilent 1813-1899
Ovenized Crystal Oscillator Assembly, 10 MHz
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Manufacturer: Keysight / Agilent