Racal 27C522-02 25-Pin Male to 34-Pin Female DSU CSU Modem Adapter DB25 IDC

Racal 27C522-02 25-Pin Male to 34-Pin Female DSU CSU Modem Adapter DB25 IDC

The Racal 27C522-02 is a passive interface adapter that converts a 25-pin DB25 male connector to a 34-pin female IDC connector for use with DSU/CSU modem equipment. It was designed for use with Racal Datacom modems and wide-area network access devices, providing the physical pin interface needed to connect DTE equipment using a standard DB25 serial port to Racal modem hardware with a 34-pin interface. No external power is required.

Specifications & What's Included

• Part Number: 27C522-02
• Manufacturer: Racal (Racal Datacom)
• Connector A: DB25 Male (25-pin D-Sub)
• Connector B: 34-Pin Female IDC
• Gender: Male to Female
• Type: Passive inline interface adapter
• Form Factor: Compact inline adapter block with thumbscrew retention hardware on DB25 end
• Housing: Two-piece beige/black plastic shell
• Includes: Adapter only; no cables included

Applications

Racal Datacom was a major British manufacturer of wide-area networking and data communications equipment from the 1970s through the 1990s, producing modems, DSU/CSU units, multiplexers, and network access devices widely deployed in corporate and government telecom networks. The 27C522-02 adapter is a purpose-built interface accessory for connecting DTE devices — such as routers, terminals, or host systems with standard RS-232 DB25 ports — to Racal modem or DSU/CSU hardware that uses a 34-pin IDC interface. This type of adapter was commonly needed when integrating Racal equipment into mixed-vendor environments or replacing cabling assemblies. Today these adapters are primarily sought as spares for legacy Racal Datacom installations still in service or for repair and maintenance of period WAN equipment.