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2x1 Protection Switch for DS3/E3 Signals

Interact with this product in a Layout Tool:

The 7780BPX-DS3 provides automatic changeover functionality for bypass protection of DS3 and E3 signals. Main and Standby inputs are provided, each with individual signal power measurement. If the power level of the Main input drops below the user-adjustable threshold, changeover to the Backup input will occur automatically. The switch may be configured to remain on the Backup input until the user sets the switch back to the Primary input, or the switch may be configured to automatically switch back to the Primary input once it has been detected that the signal has been restored. The switch may also be configured for manual switching operation, or switching via GPI or SNMP command.

The 7780BPX-DS3 is VistaLINK® enabled for monitoring and control over SNMP. A card edge menu system is also provided for full local monitoring and control. This high-density product occupies only one card slot and can be housed in the 1RU 7801FR frame which holds up to four single or two dual slot modules, the 3RU 7800FR frame which has a 15 slot capacity, the portable 3RU 350FR frame which has a 7 slot capacity, or a standalone enclosure which holds a single module.


  • High reliability, fully passive signal path maintains switch state and continues to pass signal in the event of loss of power to the card or frame
  • User-definable power setting for switching threshold
  • Flexible switching modes including automatic changeover or manual changeover using VistaLINK/SNMP or GPI
  • GPI and GPO provided for switch position indication and custom master/slave switching arrangements

Protected Bi-Directional DS3 Link Example

Protected Uni-Directional DS3 Link Example


Signal Input/Output

Number of Inputs 2
Number of Outputs 1
Connector BNC per IEC 61169-8 Annex A
I/O Impedance 75Ω
Insertion Loss < 2dB
Return Loss > 12dB
Isolation > 45dB

General Purpose Input

Number of Inputs 2
Type Opto-isolated, active low with internal pull-ups to +5V
Connector 2 pins plus ground on 6 pin terminal strip
Signal Level
+5V Pullup Low: -5V to +2.5V DC, High: 3.5V to 10V DC
+12V Pullup Low: -5V to +9.5V DC, High: 10.5V to 15V DC
Maximum Sink Current 15mA (input shorted to ground)
Maximum Leakage Current for Input High 200µA

General Purpose Output

Number of Outputs 1
Type "Dry Contact" relay contacts - normally open & normally closed contact provided
Connector 3 pins on 6 pin terminal strip


Voltage 12V DC
Power 4 watts


Number of Slots 1

Ordering Information

7780BPX-DS3 2x1 Protection Switch for DS3/E3 Signals

Ordering Options

Notes Rear plate must be specified at time of order - eg: [model]+3RU
Rear Plate Suffix
+1RU 1RU rear plate for use with 7701FR Multiframe
+SA Standalone Enclosure Rear Plate
+3RU 3RU rear plate for use with 350FR, 7700FR-C or 7800FR Multiframes


350FR Portable Multiframe which holds 7 single slot modules
7700FR-C 3RU Multiframe which holds 15 single slot modules
7800FR 3RU Multiframe which holds 15 single slot modules
7701FR 1RU Multiframe which holds 3 single slot modules
S7701FR 7700 Series Standalone Enclosure