The Rohde & Schwarz EZ-12 Antenna Impedance Converter is a broadband matching unit that interfaces high-impedance antennas with the low-impedance inputs of test receivers and spectrum analyzers. Designed specifically for measuring interference voltages at vehicle-mounted antenna outputs, it delivers accurate EMC characterization across the long-, medium-, and shortwave bands while meeting CISPR 25 requirements. The unit maintains flat frequency response, high sensitivity, and high overload capacity to ensure measurement reliability under demanding test conditions.
– Technical Specifications
• Frequency Range: 150 kHz to 30 MHz
• Input Impedance: >100 kΩ // 10 pF (at 1 MHz, CISPR 25 compliant)
• Nominal Gain: +10 dB
• Transducer Factor: −10 dB
• Frequency Response: Flat
• Power Supply: 10 V (sourced from R&S test receivers, spectrum analyzers, or external supply such as HZ-9)
– Key Features
• Remote-controlled FM range switch enables automatic switchover for interference voltage measurements in the FM band using the same antenna
• Measures open-circuit voltage directly at vehicle antenna cable output
• Factory-calibrated in accordance with CISPR 25 standards using dummy antenna methodology
• High-impedance input (>100 kΩ) permits connection of vehicle-mounted antennas without loading effects
• Low-impedance output interfaces directly with standard test receiver and spectrum analyzer inputs
– Typical Applications
• Conducted emissions testing on automotive antenna systems per CISPR 25
• Interference voltage characterization in LW, MW, and SW bands
• Vehicle-mounted antenna EMC assessment
• Broadband antenna matching for laboratory and field measurement campaigns
– Compatibility & Integration
Operates with Rohde & Schwarz test receivers (ESW, ESR, ESL) and spectrum analyzers. Supports external power supplies delivering 10 V when integrating with non-R&S measurement equipment. Compatible with R&S ELEKTRA software environment for automated test sequencing and data acquisition.

















