Unholtz Dickie Corp
Call Us! (203) 265-3929

CVA Signal Conditioners

  • 4 (CVA-4) or 8 (CVA-8) channels
  • Operates with piezo accelerometers, remote charge pre-amps and self-amplified accelerometers
  • Switchable 10, 100 mV/g (or mV/U) output for controllers
  • Three pole low-pass filtering
  • Dial-A-Gain input sensitivity normalization
  • Buffered monitor outputs on front panel
  • Low cost per channel

The models CVA-4 and CVA-8 are designed to be a low-cost accessory for the APEX SL Windows-based vibration control workstation. They provide either 4 or 8 channels of conditioned acceleration signals for the control or measurement inputs of the Windows-based vibration control workstation or other vibration controllers.

Download Instrumentation Bulletins



4 or 8 channels of signal conditioning with separately regulated power supplies for each charge amplifier. Common signal references for all channels.


  • Charge Input: Any single-ended piezoelectric transducer with shunt resistance greater than 10 megohms - Source capacitance of 50 nF causes less than 0.1% gain change - Max. input 13,000 pC (1-10 pC/g); 130,000 pC (10-100 pC/g).
  • Voltage Input: Coaxial connection to a remote pre-amp/self-amplified accelerometer. Constant current internally adjustable from 2 to 6 mA - 24 VDC compliance voltage.
  • Charge Calibration: Provides a series 1,000 pF ± 1/2% capacitor for connection to any charge input.
  • Voltage Calibration: Provides decoupling of the DC current from the external calibration signal source after connection to any voltage input.


  • Rear Panel: BNC output connector ± 10 V pk at 10 mA total current. Switch selection of 10 or 100 mV/g sensitivity.
  • Front Panel: BNC output connector with same characteristics as rear panel connector - buffered from rear panel connector and short-circuit protected.

Input Sensitivity Normalization

Provided by a range switch (10 or 100 mV-pC/g max) and a precision 10 turn dial for two ranges: 1-10 pc-mV/g and 10-100 pC-mV/g (actually 0.3 to 10.3 and 3 to 103 pC-mV/g).


.005 pC rms + .0015 pC/1nF source capacitance RTI plus 0.1 mV p-p RTO with 5 kHz LPF.

Front Panel Controls

  • Input sensitivity range (10 max, 100 max)
  • Input sensitivity vernier (0.03 to 1.03 times max value) - 10 turn precision potentiometer and dial
  • Input selector (charge or voltage)
  • Output sensitivity (10, 100 mV/g)
  • Buffered output (isolated BNC)

Rear Panel Controls/Connectors

  • Charge input (isolated 10-32 miniature coax)
  • Voltage input (isolated BNC)
  • Output (isolated BNC)
  • Int-ext ground switch
  • Line voltage selector switch (115/230V)
  • Charge and voltage calibration connectors


  • Standard Unit Power: 105-125/210-250 VAC; 50/60 Hz, 8 VA (CVA-4), 12 VA (CVA-8)
  • Standard Unit Dimensions: 17"W x 3.4"H x 13"D with brackets suitable for mounting in a standard 19 inch rack.
  • Frequency Response: A three-pole Butterworth filter determines the high frequency response. The frequency (fu) is typically chosen to be 3 kHz, but may be customer specified at 1, 2, 5, or 10 kHz.