The Keysight (Agilent) 34905A is a Dual 4-Channel RF Multiplexer module designed for the 34970A and 34972A Data Acquisition/Switch Units. It provides broadband switching capabilities for high-frequency and pulsed signals in 50 Ohm systems, featuring a usable bandwidth of up to 2 GHz. Built with two independent, unterminated 1x4 multiplexers, it features common low shielding and switched center conductors to route test signals cleanly. It includes ten 1.2-meter BNC-to-SMB adapter cables to interface directly with standard BNC connections.

Specifications

Physical

ParameterValue
Power SupplyPowered via mainframe backplane
Operating Temperature0°C to 55°C

RF Input/Output Channels

ParameterValue
Number of Channels8 (arranged as two independent 1x4 multiplexers)
Multiplexer ConfigurationDual 1x4
Characteristic Impedance50 Ω
Connector TypeSMB (on module)
Isolator/Shielding TypeCommon Low (switched center conductor, common shield)
Termination OptionUnterminated

RF Performance Specifications

ParameterValue
Frequency RangeDC to 2 GHz
Insertion Loss (100 MHz)< 0.20 dB
Insertion Loss (500 MHz)< 0.25 dB
Insertion Loss (1 GHz)< 0.50 dB
Insertion Loss (2 GHz)< 1.00 dB
VSWR (100 MHz)< 1.15
VSWR (500 MHz)< 1.25
VSWR (1 GHz)< 1.35
VSWR (2 GHz)< 1.45
Isolation (100 MHz)> 60 dB
Isolation (500 MHz)> 50 dB
Isolation (1 GHz)> 45 dB
Isolation (2 GHz)> 35 dB
Crosstalk (100 MHz)< -60 dB
Crosstalk (500 MHz)< -50 dB
Crosstalk (1 GHz)< -45 dB
Crosstalk (2 GHz)< -35 dB
Propagation Delay< 3.0 ns
Rise Time< 300 ps
Phase Matching Between Channels< 100 ps (between channels of the same bank)

DC & Signal Carrying Capacity

ParameterValue
Maximum Switching Voltage42 V (DC or AC peak)
Maximum Switching Current0.7 A
Maximum Carry Current0.7 A
Maximum Switching Power (DC)10 W

Relay Specifications

ParameterValue
Relay TypeMiniature coaxial reed
Mechanical Life Cycles100,000,000 cycles

Mainframe Integration & Control

ParameterValue
Compatible MainframesKeysight / Agilent 34970A, 34972A
Module Slot Occupancy1 slot
Built-in Relay Cycle CounterYes

Physical Characteristics

ParameterValue
Included Accessories10 BNC-to-SMB 50 Ω adapter cables (1.2m)
Cable OptionsOption 001 deletes BNC-to-SMB adapter cables

Environmental & Safety

ParameterValue
Operating Temperature Range0°C to 55°C
Storage Temperature Range-40°C to 70°C
Operating Humidity Range (Non-condensing)Up to 80% R.H. at 40°C

Technology

RF Switching / Multiplexing

Applications

Automated Test Equipment (ATE), RF and Microwave Routing