PC104 Synchro/Resolver Measurement Board

PC104 Synchro/Resolver Measurement Board

Model PC/104 73SD4

PC104 Synchro/Resolver Measurement Board

NAI’s 73SD4 is a DSP-based, PC104-compliant Synchro/Resolver Measurement Board with six separate, isolated channels. These channels can incorporate up to six Synchro/Resolver-to-Digital Tracking Converters in a stack-through module. Each channel also produces differential incremental encoder (A & B) outputs (with programmable resolution) and a zero-degree marker pulse. Commutation outputs are available for 4-, 6-, or 8-pole brushless DC motors that eliminate the need for Hall Effect sensors, thereby reducing both processor time and bus traffic.

Standard features include 16 TTL Digital I/O, Background Built-in-Test (BIT) for continuous checking and reporting on the health of each channel, extensive diagnostics, and digital velocity outputs. Specifically designed for rugged defense, commercial aerospace, and industrial applications, the 73SD4 supports optional reference and turn counters.     Requires forced air cooling.


  • Six isolated channels for up to six separate Synchro/Resolver-to-Digital Tracking Converters
  • Tracking rate to 150 RPS
  • 16-bit resolution
  • 1 arc-minute accuracy
  • Programmable speed ratios: 1:1 to 255:1
  • Angle change alert
  • Digital velocity output
  • Auto-phase correction
  • Continuous Background Built-in-Test (BIT)
  • Reference-loss, signal-loss, and latch features
  • Programmable bandwidth
  • Optional Hall Effect commutation outputs
  • Optional programmable encoder (A & B) and index outputs
  • Optional on-board reference supply
  • Software Support Kit (SSK) and drivers are available
Document DownloadsDate
73SD4 Operations Manual
Application Note: Encoder/Commutation Option


Note: Linux Driver(s): All Linux driver / source code are provided as is without change support.
News ItemsDate
Distributed I/O Data and Processing Architectures
Modern military platforms continue to place an ever greater reliance on electronics for their operation.