Advanced Test and Measurement
Instruments and Power Supplies

Rohde and Schwarz HM8123

3GHz Frequency Counter with TCXO or OCXO

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  • Measurement range: DC to 3 GHz
    • Input A/B (BNC): DC to 200 MHz
    • Input C (SMA): 100 MHz to 3 GHz 
  • Input impedance A/B: 50 Ω or 1 MΩ (switchable), sensitivity 25 mV
  • Input impedance C: 50 Ω, sensitivity 30 mV
  • 10-digit resolution (at 10 s gate time)
  • Nine measurement functions, external GATE and ARMING connectors (BNC)
  • External reference input/output (10 MHz) via BNC connector
  • HM8123: TCXO (temperature stability: ±0.5 x 10-6), HM8123-X: OCXO (temperature stability: ±1.0 x 10-8)
  • RS-232/USB dual interface, optionally IEEE-488 (GPIB)
  • Fanless design
  • This product series was previously branded HAMEG

Product Variants

Model Price


3GHz Frequency Counter TCXO (temperature stability ±0.5x10-6)


3GHz Frequency Counter OCXO (temperature stability ±1.0x10-8),
Model Description Price
IEEE-488 (GPIB) Interface (galvanically isolated) for series 81004)
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