The Agilent/Keysight 37201A is an HP-IB bus extender that converts parallel HP-IB data into serial bit streams for long-distance transmission, then reconverts to parallel format at the receiving end. It enables instrument communication beyond standard HP-IB cable limitations, supporting distances up to 1000 meters over twin-pair cable or virtually unlimited range via modem links. Full-duplex operation allows simultaneous bidirectional data flow with automatic error checking and retransmission of corrupted packets.
– Technical Specifications
• Data Conversion: Parallel HP-IB to serial and serial back to parallel HP-IB
• Communication Mode: Full-duplex bidirectional
• Twin-pair Cable Range: Up to 1000 meters at nominal 20 kbit/s serial data rate
• Modem Link Range: Virtually unlimited over private lines, leased lines, or public switched telephone network
• Serial Interface Standards: EIA RS-232C, CCITT V.24, and V.28
• Asynchronous Data Rates: 150, 300, 600, and 1200 bit/s
• Synchronous Data Rates: Up to 19.2 kbit/s
• Multi-point Configuration: Supports up to 31 remote sites on leased line networks
• Modem Compatibility: Wide range of synchronous and asynchronous modems
• Signal Isolation: Transformer coupling for common mode immunity
• HP-IB Function Support: Full IEEE 488-1978 except Parallel Poll and Pass Control
• Standards Compliance: IEEE 488-1978, ANSI MC1.1, IEC 625-1
– Key Features
• Transparent integration—typically requires no software modification
• Auto-dialing support with RS-366/CCITT V.25 parallel interface for program-controlled connections
• Manual dialing capability over public switched telephone network
• Automatic error-checking protocol with corrupted data retransmission
• Suitable twin-pair cable available as accessory (HP Part Number 8120-1187)
– Typical Applications
Extending HP-IB instrument systems across distances impractical for standard parallel cabling, including remote laboratory configurations, multi-site test facilities, and distributed measurement systems over dial-up or dedicated communication links.
– Compatibility & Integration
Fully compatible with IEEE 488-1978 HP-IB systems. Operates with legacy and contemporary synchronous/asynchronous modems. Requires standard RS-232C serial connection and HP-IB interface.
















