HP 7004B X-Y Recorder Flatbed Chart Recorder 17171A 17172A 17173A For Parts

HP 7004B X-Y Recorder Flatbed Chart Recorder 17171A 17172A 17173A For Parts

The HP 7004B is a dual-axis flatbed X-Y chart recorder made by Hewlett-Packard. Flatbed X-Y recorders use servo-driven pen carriages to plot analog signals on paper along two independent axes simultaneously, producing accurate graphical records of voltage vs. voltage or voltage vs. time relationships. This unit is equipped with three option modules — the 17171A DC Preamplifier, the 17172A Time Base, and the 17173A Null Detector — and is being sold as-is for parts or repair.

Specifications & What's Included

• Make / Model: Hewlett-Packard HP 7004B X-Y Recorder
• Recorder type: Dual-axis flatbed X-Y (servo-driven pen)
• Included option — X1 slot: HP 17171A DC Preamplifier
• Included option — X2 slot: HP 17172A Time Base
• Included option — Y1 slot: HP 17171A DC Preamplifier
• Included option — Y2 slot: HP 17173A Null Detector
• DC Preamplifier range: 0.5 mV/inch to 10 V/inch (mV/INCH and VOLTS/INCH scales)
• Time Base sweep rate: 0.5 to 100 sec/inch
• Power: 115/230V ±10%, 48–440Hz, 100VA max (front-panel voltage selector)
• Fuse: 115V — 1A T; 230V — 500mA T
• Rear interface: DB25 parallel connector (P902/J903), IEC AC inlet
• Front panel controls: SERVO, PEN, LINE, and CHART on/off rocker switches; SETUP/RECORD toggle
• Ruler scale along platen edge for chart alignment
• Known defect: pen holder is broken
• Known defect: one internal circuit board is shorted
• Sold as-is for parts or repair — unit is not functional

Applications

Flatbed X-Y recorders like the HP 7004B were widely used from the 1960s through the 1980s in laboratory, scientific, and engineering environments to create permanent paper plots of analog data. Common applications included plotting frequency response curves, transfer functions, stress-strain curves, and calibration data in electronics labs, materials testing, and research facilities. The dual-axis design allowed one channel to drive the pen in the X direction while a second channel drove it in the Y direction, producing smooth, continuous curves directly on chart paper. The modular plug-in architecture of the 7004B — with swappable preamplifier, time base, and null detector modules — made it flexible across a variety of input signal types and measurement tasks. These recorders have largely been replaced by digital data acquisition systems and PC-based plotting software, though they remain sought after for parts, restoration, and legacy lab applications.