The Astronics / C&H Technologies VX491C is a single-slot C-size VXI counter/clock module engineered for precise timing, pulse generation, and event measurement in data acquisition and test systems. It delivers a stable 10 MHz master clock source with multiple derived outputs, six 32-bit counters, and integrated time-of-day clock functionality. The module operates within VXIbus-compliant mainframes and supports flexible triggering, programmable interrupts, and SCPI-compatible control.
## Technical Specifications
• **Module Type:** Counter/Clock VXI Module, C-size, single-slot
• **VXIbus Compliance:** ANSI/IEEE Std. 1014-1987, IEC 821, IEC 822, VXIbus Rev 1.4
• **Master Clock:** On-board oven-controlled 10 MHz oscillator
• **Clock Outputs:** Four derived outputs from 10 MHz master clock
• **Counters:** Six 32-bit counters
• **Time-of-Day Clock:** Included
• **Connectors:** Standard VXIbus backplane (P1 and P2)
• **Form Factor:** 23.3 × 34 cm (C-size)
## Key Features
• Oven-controlled 10 MHz master oscillator ensures timing stability
• Multiple clock outputs derived from master reference frequency
• Programmable interrupts on master clock drop-out, counter roll-over, match conditions, periodic intervals, and set time-of-day events
• Flexible trigger sourcing from front panel or VXI Bus
• 32-bit counter resolution enables high-resolution event and interval measurement
• Integrated time-of-day tracking for absolute time reference
## Typical Applications
• Precise timing and clock generation for data acquisition systems
• Pulse stimulus generation with programmable characteristics
• Pulse counting and time period measurement
• Trigger signal generation for synchronized test equipment
• Event timing in automated test environments
## Compatibility & Integration
Designed for integration into VXIbus-compliant mainframes and systems. The module operates with VXIplug&play and SCPI standard control protocols, enabling seamless integration into modular instrumentation architectures. Power is supplied by the VXIbus mainframe via P1 and P2 connectors; cooling is provided by mainframe airflow management.
