Classic Electronic Restoration, Vacuum Tube Audio, Technical History, Photography

In a recent post, I documented the replacement of a difficult to read VFD display with a modern TFT display in my Advantest R6581T. It was unequivocally worthwhile and has been working extremely well. Nowl, I am at it again, but his time the subjects are the HP 3478A 51/2 digits DMM and the HP…

The HP 3445A is a compact, rackable plugโin digital voltmeter from HewlettโPackardโs classic 34xx family, offering fast autoranging DC and AC measurements, clear numeric readout, and systemโfriendly outputs that made it a staple in production racks and vintage labs. HP 3445A overview The 3445A is a plugโin digital voltmeter designed for HPโs modular instrument systems,…

The HP 3440A is a plugโin style digital voltmeter designed for HP modular systems and bench racks. It was offered as a versatile measurement unit with a focus on accurate DC voltage and resistance readings, remote triggering, and digital outputs for system automation. With the appropriate plug-in, it can also measure AC voltage, and DC…

The HP 8443A is a compact, rackable tracking generator and frequency counter designed to work with HP spectrum analyzers; it produces a swept CW output that follows the analyzer marker for easy swept-response and markerโbased measurements, while offering a builtโin counter and stable 1 MHz timebase for accurate frequency readout. Overview The HP 8443A Tracking…

The HP 3245A Universal Source is a versatile precision instrument that combines DC and AC signal generation, offering both high-resolution DC outputs and synthesized AC waveforms up to 1 MHz. Function Details DC Outputs 24-bit resolution, 60 ppm accuracy, voltage & current modes AC Outputs Sine, square, triangle, ramp, pulse up to 1 MHz (100…