The 3497A Data Acquisition / Control Unit combines the capabilities of several instruments and is a basic building block of an automatic data acquisition and control system. Includes a front-panel keyboard and display, a non-volatile real time clock, and an HP-IB interface. The 3497A card cage holds up to five plug-in assemblies designed to perform various functions. With this kind of flexibility and multiple configuration possibilities, you'll find that this system will fulfill many of your application requirements. This price is for the mainframe only, call for more information. Need more room? Get the 3498A Extender. It holds 10 more plug-ins and you can daisy-chain it to more 3498A's. Manufacturer's Options Option 001 = 5 1/2 Digit DVM and Current Source (44420A) Option 010 = 20 Channel Relay Multiplexer Assembly (44421A) Option 020 = Relay Multiplexer Assembly with thermo-couple compension (44421A) Option 030 = 20 Channel FET Multiplexer Assembly (44423A) Option 050 = 16 Channel Isolated Digital Input/In