Boxed bus couplers

Greenwood Boxed Bus Couplers  were introduced in 1999 and over the last decade they have become well established in the lab and field test rig market, with an installed base in the thousands.  

The MIL-STD-1553B bus LAN typically comprises of bus couplers (boxed or in-line), terminators and twinax cabling, and concentric twinax connectors. The purpose of the coupler is to reduce reflections and maintain signal impedance levels. Both ends of the bus, whether it includes one coupler or a series of couplers connected together, must be terminated with 78 Ohm terminators. Some couplers have built in terminators and are generally used at the end of the bus in multi-coupler applications. Internally terminated couplers are less flexible in where they can be used and are best specified in bus designs that will remain fixed over time. A higher impedance terminator (1000 to 3000 Ohms) may be used in applications to simulate a future load from an unspecified device.

The standard stub jacks supplied are 3-lug TRB concentric twinax connectors. 2-lug, 4-lug and threaded versions are available to special order. Typically, the cable used to connect bus and stub devices is 78 Ohm Twinax cable. High temperature and lab test versions are available from stock. 

General Specifications
Transformer Turns Ratio:1.41:1
Fault Isolation Resisters59 Ohm, 2 Watt 1%
Operating Temperature-40 to + 85 Deg C
Overshoot/Ringing± 1.0v max.
Droopless than or equal to 20%
Min. Primary Open1-stub - 3000
Impedance (Ohms):2-stub - 1500
3-stub - 1000
4-stub - 750
5-stub - 600
6-stub - 500
7-stub - 430
8-stub - 375
Connectors:TRB 3-lug Jacks
Other connector types are

  1. GE-10101, 1-stub coupler
  2. GE-10102, 2-stub coupler
  3. GE-10203, 3-stub coupler
  4. GE-10204, 4-stub coupler
  5. GE-10205, 5-stub coupler
  6. GE-10206, 6-stub coupler
  7. GE-10207, 7-stub coupler
  8. GE-10208, 8-stub coupler