The Racal Instruments 2461CD is a VXIbus universal counter timer module engineered for high-performance test and measurement applications requiring broad functionality and flexible configuration. This module integrates eleven automatic measurement functions into a single card, reducing system size and cost while maintaining outstanding resolution across frequency, time interval, and pulse characterization measurements. The 2461CD supports 2- or 4-channel configurations and operates up to 200 MHz with 10 digits of resolution per second, extending to 1.3 GHz with Option 41.
Technical Specifications
Measurement Capabilities
• Frequency: up to 200 MHz (10 digits/second); 1.3 GHz with Option 41
• Time interval: 1 ns resolution (single-shot), 100 ps resolution (average mode)
• Period, time interval delay, rise time, fall time, pulse width
• Frequency ratio (channels 1-to-2 or 3-to-2)
• Totalize, phase, and DVM (MAX, MIN, DC voltages)
Input & Signal Conditioning
• 2- or 4-channel module configuration
• Selectable low pass filters per input channel with adjustable hysteresis
• Independent 50 kHz low pass filters available on each channel
• Programmable sensitivity for low-level and low slew rate signals
Dynamic Range
• x1 attenuation: 5 V pk-pk (<50 MHz), 2.5 V pk-pk (<100 MHz), 1.5 V pk-pk (<200 MHz)
• x10 attenuation: 50 V pk-pk (<50 MHz), 25 V pk-pk (<100 MHz), 15 V pk-pk (<200 MHz)
Measurement Control & Storage
• Nine arming modes with external input or VXI TTL trigger line selection
• Programmable measurement timeout for signal absence scenarios
• Internal memory: up to 14,000 readings
• External arming signal support for measurement start control
– Key Features
Time Error Correction (TEC) minimizes measurement time without performance degradation. Automatic pulse characterization with narrow hysteresis bands simplifies rise time, fall time, and pulse width analysis. Selectable sensitivity and low pass filtering enable operation in electrically noisy environments.
– Typical Applications
Automated test systems, laboratory measurement instrumentation, frequency and timing analysis, pulse characterization, and integrated VXI-based test platforms requiring multifunction counter-timer capability.
– Compatibility & Integration
Part of the Racal 2460 Series VXIbus module family. Compatible with standard VXI chassis and trigger infrastructure.
