Astronics / EADS / Racal 1261B 13-Slot High-Performance VXI Mainframe

The Astronics/EADS/Racal 1261B is a 13-slot VXI mainframe engineered for high-performance test and measurement applications. This mainframe delivers abundant power with minimal ripple and noise, supporting both benchtop and rack-mount configurations. Available in 7U and 9U versions with optional extended cable trays, it accommodates diverse system architectures while maintaining strict VXIbus compliance and advanced thermal management.

## Technical Specifications

**Power Delivery**
• Standard 1261B: 925 W total usable power @ 55° C
• 1261B-Linear variant: 760 W usable/available power with separate linear supply optimized for RF and microwave applications
• Ultra-low power supply noise (Linear variant)
• Advanced design with minimal ripple and noise
• High dynamic current capabilities for crisp waveforms and accurate measurements
• Full over-voltage and under-current protection
• Direct backplane connection for optimal power delivery

**Thermal Management**
• Fourth-generation cooling system meeting highest VXI-8 curves
• Pressurized plenum system for even front-to-back and side-to-side airflow distribution
• Molded card guides direct airflow through modules
• Fault-tolerant rear-pluggable cooling assembly with three fans; operation maintained with two fans on single fan failure
• HI/LO cooling switch on basic units to manage audible noise
• Variable-speed cooling system on units with system monitor, adjusting based on worst-slot temperature rise
• Rear switch selection for maximum cooling mode

**Configuration Options**
• 7U Version: Rear air intake, top exhaust (benchtop/space-limited installations)
• 9U Version: Side air intake, rear exhaust (rack-mount; minimizes chimney effects); includes 2.25″ cable tray
• Option 21: 1U cable tray increase (10U total chassis height, 3.9″ tray)
• Option 22: 2U cable tray increase (11U total chassis height, 5.6″ tray)

**Standards Compliance**
• VXIbus specification Rev. 2.0
• VXI specification B.7.2.3
• VXIplug&play specifications supported

## Key Features

• Snap-on covers for unused slots manage airflow distribution
• Quick-check diagnostic connector for power supply voltage, current, and VXI signal verification
• Standard Monitoring System (SMS) for automatic mainframe parameter checking

## Typical Applications

Automated test systems, RF/microwave measurement platforms, defense and aerospace instrumentation, high-reliability production test environments.