North Atlantic 8500-F121 Angle Position Indicator

The North Atlantic 8500-F121 is a precision synchro/resolver-to-digital converter that transforms analog angular data into high-resolution digital representations. This angle position indicator delivers 0.01° display resolution and 0.03° accuracy per channel across two independent inputs, with auto-ranging voltage detection and automatic phase shift compensation. The unit accepts line-to-line inputs from 10–100 V across selectable frequency bands (47–440 Hz or 360–1200 Hz) and outputs digital angle data via parallel BCD, front panel display, and optional IEEE-488 interface. Designed for rack-mount half-width installations, bench configurations, and computer-integrated systems, the 8500-F121 combines field serviceability with operator-friendly setup error warnings and selectable tracking speed control.

– Technical Specifications

• Converter Type: Synchro/Resolver-to-Digital
• Display Resolution: 0.01°
• Accuracy: 0.03° per channel (two independent channels)
• Input Signal Voltage: 10–100 V line-to-line, auto-ranging
• Frequency Range: 47–440 Hz or 360–1200 Hz (selectable)
• Phase Angle Compensation: Up to ±80°
• Tracking Speed: Selectable low/high bandwidth or remote control; settling time less than 1.5 seconds for 180° step change at low speed, 47–440 Hz
• Power Input: 115 V ac or 230 V ac, 47–440 Hz; selectable via internal switch

– Key Features

• Two independent measurement channels with identical accuracy specifications
• Automatic input voltage ranging eliminates pre-selection and pre-programming
• Phase angle compensation up to ±80° maximizes measurement accuracy under quadrature mismatch
• Setup error warnings alert operators to loss of reference, faulty connections, or excessive synchro rates
• Field-serviceable design with no sealed assemblies
• Flexible power input from line cord or rear parallel I/O connector (J1)

– Interfaces & Integration

• Parallel BCD outputs (standard)
• IEEE-488 remote sensing and control interface (optional)
• MATE/CIIL interface (optional, available with IEEE-488 and parallel)
• Front panel terminals for bench use; rear connectors for rack integration

– Typical Applications

Computer-controlled systems, fixed installations, aerospace and precision instrumentation, and laboratory bench configurations requiring high-resolution angular measurement and multi-output digital conversion.