HP 70950B optical spectrum analyzer repair

The HP 70950B improves on the 70950A with tighter wavelength accuracy (±0.05 nm after user calibration) and −95 dBm sensitivity in the 1250–1600 nm band. The 4/8-width module form factor installs in the HP 70004A or 70001A mainframe. HP discontinued support for this module family years ago; the 70950B is now serviced only by independent shops.

Optical path contamination is the leading cause of sensitivity loss on the 70950B - the −95 dBm sensitivity floor requires clean optics throughout the signal path. Grating assembly wear produces wavelength accuracy errors and erratic sweep behavior. The module interface contacts are also a known wear point: insertion and removal over years causes contact oxidation that produces intermittent errors. On the electronics side, capacitor aging causes noise floor increases and signal processing irregularities.

We test each 70950B in a mainframe against calibrated DFB references, verify sensitivity, wavelength accuracy, and RBW. Component-level board repair, optical cleaning and alignment, and NIST-traceable calibration complete the service. Cal cert included.

Estimate: $100 flat-rate. Turnaround 1–3 days. International shipping available.