The Astronics/EADS/Racal 1260-38T is a high-density multiplexer module designed for signal routing and data transmission in automated test equipment, continuity testing, and telecommunications systems. This C-size single-slot VXIbus module supports user-configurable multiplexer topologies ranging from sixteen independent 1×8 units to cascaded 1×128 configurations under program control. Both two-wire and four-wire switching modes are supported across a bandwidth exceeding 30 MHz, with insertion loss below 0.1 dB at 100 kHz and isolation greater than 45 dB at 10 MHz. Electromechanical relays provide switching capability up to 220 VDC/VAC at 2 A maximum, with total power handling to 60 W or 125 VA. The module integrates VXIplug&play drivers for LabWindows/CVI and LabVIEW frameworks, requiring a Racal Instruments Option 01 or Option 01T switch controller for operation.
## Technical Specifications
• **Form Factor:** C-size, single-slot VXIbus module
• **Multiplexer Configurations:** Sixteen 1×8 units; cascadable to 1×128
• **Switching Modes:** Two-wire and four-wire
• **Bandwidth (-3 dB):** >30 MHz (1×8 configuration)
• **Insertion Loss:** <0.1 dB @ 100 kHz; <0.25 dB @ 1 MHz (1×8); <0.2 dB @ 1 MHz (1×128); 45 dB @ 10 MHz (1×8)
• **Crosstalk:** <−50 dB @ 10 MHz (1×8)
• **Maximum Switching Voltage:** 220 VDC or 220 VAC
• **Maximum Switching Current:** 2 ADC or 2 AAC
• **Maximum Switching Power:** 60 W; 125 VA
• **Path Resistance:** <750 MΩ (1×8, two-wire)
• **Insulation Resistance:** 10⁹ Ω
• **Thermal EMF:** <15 µV (1×8, two-wire)
• **Capacitance:** <5 pF channel to chassis (1×8)
• **Switching Time:** <5 ms maximum
## Key Features
• Electromechanical relay-based architecture
• Front panel guard grounds minimize crosstalk and enhance isolation
• Operating temperature range: 0°C to 55°C
• Storage temperature range: −40°C to 75°C
• Shock rating: 30 g, 11 ms, ½ sine wave
• Vibration: 0.013 in. peak-to-peak, 5–55 Hz
• CE Mark compliance for RF emissions and electrical safety
## Compatibility & Integration
Requires Racal Instruments Option 01 (native command set) or Option 01T (message-based and register-based operation). VXIplug&play support included for Microsoft Win32 API-based frameworks.
