A-A-55140 Document
Connectors, Electrical, IEEE 488 Compatible, Rectangular, Miniature, Polarized Shell, Receptacle, Shielded, 24 Position, Flat Cable Terminating, Insulation Displacement, Screw or Bail Locking, Preassembled Construction
Bail-Locking, IDC flat-ribbon cable GPIB Connector
Mil specification A-A-55140 defines an IEEE-488 connector which uses a cable termination via IDC [Insulation Displacement Connector]. The GPIB side is secured by a locking Bail. This connector fits on the equipment side of the interface, the cable side would mate to it, and be secured by the locking bail.
This particular 55140 connector would mate with a 55094 IEEE488 Connector which contains the latch portion of the bail-lock.
Main description of the General Purpose Interface Bus [GPIB]. Additional IEEE488 CIDs [Government Commercial Item Description documents].
General requirements for a polarized shell, receptacle, electrical digital interface bus connector. This connector can be used in applications that require conformance to the IEEE 488 interface standard [HPIB], and require termination of a 1.27 millimeters (.050 inch) flat cable. Connectors are intended for commercial or industrial applications and shall not be used in military systems needing stringent environmental and electrical requirements.
Terminology note; The military and much of the government use the phrase Flat Cable, while much of the commercial industry uses the phrase ribbon cable. Both terms mean the same thing and reference the same style of cable, but there is a difference between the two camps. In other words when searching government documents you will not find a reference to a ribbon cable.
Technical Note; The GPIB interface has been active for thirty years so there are thousands of pieces of gear fielded. As long as the equipment continues to function GPIB will remain in the field. However there is a replacement in the LXI Bus, or LAN eXtensions for Instrumentation which uses the faster Ethernet Interface. So the advice is; do not directly specify a piece of equipment just because it has an IEEE488 interface on it unless there is a direct requirement for the interface. Of course the more appropriate reason for looking up this topic is to find a connector replacement for a damaged cable.
Editor note; This is one of these rear cases when I'm really not sure what a particular phrase in the title of a document is referring to. The title specifies, Pre-assembled Construction, to a connector that for all intents and purposes is pre-assembled, so I really can't say what that means. Maybe the top portion of the IDC cap is already attached to the main body of the connector, or maybe the nuts that form the locking portion of the flange are permanently installed. It might even refer to the attachment of the locking Bail, but each of these things seem common place, so I leave it to the reader to decipher.
