Keysight / Agilent Option 50 / 8-Bit Digital I/O Assembly Module
  • Keysight_Agilent_Option_50_8_Bit_Digital_View1_2017712104235
  • Keysight_Agilent_Option_50_8_Bit_Digital_View2_2017712104235

Keysight / Agilent Option 50 / 8-Bit Digital I/O Assembly Module

Part Numbers: 44465A, 44465-66513, 44465-66503

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CE labeled RoHS Compliant
We typically stock RoHS compliant / CE marked equipment for this Keysight / Agilent Option 50 / 8-Bit Digital.
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Stock # 92519-1
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Keysight / Agilent 3421A Data Acquisition / Control Unit

  • HP-IL Interface
  • Optional HP-IB Interface
  • Fully Programmable 5 1/2 Digit Voltmeter
  • Programmable Power Down, Standy Mode
  • Memory Storage for 30 Readings
  • Programmable Counter


The Keysight / Agilent 3421A Data Acquisition / Control Unit is a fully programmable unit combining precision measurement capability with process monitoring and control functions. When interfaced to an HP computer (such as the HP-85) or handlheld calculator (such as the HP-41C/CV), the 3421A forms a versatile, easy to use data acquisition and control system.

The standard 3421A consists of a mainframe, a built-in 5 1/2 digit voltmeter, a 10 kHz counter, and an HP-IL controller interface. Compensated temperature conversion using T-type thermocouples is also built in. The mainframe can hold up to three option assemblies. Available options include a 10 Channel Multiplexing Assembly, an 8-Bit Digital I/O Assembly, and a Breadboard Assembly for custom circuit design. In addition, an optional HP-IB interface or a 12V Battery Option is available.

Typically, at least one Multiplexing Assembly (44462A or option 020, 021, or 022) is used in the 3421A. This assembly provides 10 channels for signal input. A temperature reference junction is built in to each assembly for thermocouple compensation. In addition, two of the channels can be configured as actuators for controlling motors, alarms, etc.

The 8-Bit Digital I/O Assembly (44465A or option 050) provides an 8-bit input port and an 8-bit output port. Typical uses for this assembly include monitoring limit or position switches, and low voltage actuating. The 3421A command set provides for individual bit control as well as 8-bit word control.

If neither of these assemblies meet your needs, Option 040, the Breadboard Assembly is avaiable. This option permits you to custom design and build your own measurement or control assembly.

Product Family: 3421A, 3421 A, 3421-A

Important Notice: Please note that any additional items included with this equipment such as accessories, manuals, cables, calibration data, software, etc. are specifically listed in the above stock item description and/or displayed in the photos of the equipment. Please contact one of our Customer Support Specialists if you have any questions about what is included with this equipment or if you require any additional information.

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