The Marconi IFR Aeroflex 2437 is a 100 MHz universal counter timer engineered for precision frequency, period, and time interval measurements across laboratory and field environments. This dual-channel instrument delivers eight-digit resolution with selectable triggering, AC/DC coupling, and extended measurement capabilities including frequency ratio, multi-period analysis, and counting up to 10^7 events per second. Channel A operates DC to 10 MHz with 20–50 mVrms sensitivity; Channel B extends to 100 MHz (10–25 mVrms) and includes a UHF mode spanning 50–520 MHz at +21 dBm nominal input. The instrument features a bright 8 mm seven-segment LED display with automatic decimal placement, adjustable trigger levels from 0 V to +25 V, and optional data interface outputs for external display and control integration. Period and timing measurements resolve to 100 ps minimum across a 100 ns to 1000 seconds range. An internal 10 MHz standard and external standard input (10 kHz–10 MHz) support ratio and comparison measurements. Input impedance is approximately 1 MΩ in parallel with less than 45 pF (50Ω nominal in UHF mode). Compact portable design suits both bench and field deployment.
Technical Specifications
Frequency Measurement
• Channel A: DC to 10 MHz, 20–50 mVrms sensitivity, AC/DC coupling, ×10 attenuator
• Channel B: DC to 100 MHz, 10–25 mVrms sensitivity, AC/DC coupling, ×10 attenuator
• Channel B UHF Mode: 50–520 MHz, +21 dBm input (2.5 Vrms pd into 50Ω)
• Modes: Frequency, frequency ratio, period, multi-period, time interval, time interval averaging, counting
Timing Measurements
• Period range: 100 ns to 1000 seconds
• Period resolution: 100 ps
• Count capability: Up to 10^7 events per second
Display
• Eight-digit seven-segment LED, 8 mm character height
• Automatic decimal point placement
• Overflow indication lamp
Triggering
• Adjustable trigger level: 0 V to +2.5 V (×1 attenuator) or 0 V to +25 V (×10 attenuator)
• Positive or negative slope selection, both channels
• Status indication lamps (above, below, within range)
External Standard & Interfaces
• External standard input: 10 kHz–10 MHz, 180 mVrms (max 1.8 Vrms), 10 kΩ nominal impedance
• Internal standard: 10 MHz rear panel socket
• Optional data interface: SCX display enable, overflow output, counter/display clear, gate control, display scan inputs, decimal point and leading zero suppression outputs
– Key Features
• Dual-channel architecture with independent sensitivity and coupling control
• UHF extension to 520 MHz on Channel B
• High-resolution period measurement (100 ps)
• Selectable AC/DC input coupling and trigger polarity
• Internal and external frequency standard support
• Optional data interface for system integration
– Typical Applications
• Frequency and period calibration in RF/microwave systems
• Time interval and pulse width measurement
• Frequency ratio and comparison testing
• UHF signal characterization and validation
• Bench and field frequency standard verification
– Compatibility & Integration
Optional data interface supports PC and Mac systems via configurable output signals for display control, counting gates, and measurement synchronization.
