PC104 LVDT/RVDT Measurement Board

Model PC/104 73LD4

PC104 LVDT/RVDT Measurement Board

NAI’s 73LD4 is a PC104-compliant LVDT/RVDT Measurement Board with six separate transformer-isolated channels. The channels can incorporate up to six programmable LVDT/RVDT-to-Digital Tracking Converters in a stack-through module. Each channel is programmable for 2-, 3-, or 4-wire inputs that automatically range between 2.0 volts and 28 volts, so there is no need to purchase multiple boards set for specific inputs. Operating frequency between 360 Hz and 10 kHz can be specified. Each channel also produces differential incremental encoder (A & B) outputs with programmable resolution and a zero degree marker pulse.

Standard features include 16 TTL Digital I/O, Background Built-in-Test (BIT) for continuous checking and reporting on the health of each channel, and extensive diagnostics. Specifically designed for rugged defense, industrial, and commercial applications, the 73LD4 supports an optional reference supply.     Requires forced air cooling.


  • Six separate transformer-isolated channels
  • Requires only +5 VDC
  • 16-bit resolution
  • Continuous Background Built-in-Test (BIT) with excitation and signal loss detection
  • Self-calibrating, removal not required
  • Programmable bandwidth
  • Optional, programmable reference excitation
  • Two banks of 8 (16 total) TTL Digital I/O – input/output programmable for each bank
  • Watchdog timer and soft reset
  • 16-bit data bus
  • 360 Hz to 10 kHz
  • Galvanic isolation
  • Latch feature
  • Synthetic reference compensates for ±60° phase shift
  • No adjustments or trimming required

I/O Product Reference Guide

Document DownloadsDate
73LD4 Operations Manual
Measurement / Simulation
LVDT / RVDT Measurement, 4-CH