Vintage Test Instruments

My vintage test instrument collection is predominatly HP, with a few Tektronix and others mixed in. They are mostly rather high end instruments, with a bend on RF/microwave. When I get the instruments, as gifts, off eBay or lab rejects, they usually don't work. Or if they do, they fail shortly thereafter. Not to worry, I always get them to work. The repairs are chronicled on the CuriousMarc YouTube channel. Here you will find more detailed info and links supplementing the videos.

This section is under construction and many projects don't link to any page yet. The ones that do are at the top of the list. If you need some info about a particular item, just let me know , that's usually a good incentive for me to write up the page about the instrument and post the documentation.

Data IO 29B

PROM Programmer

It was the king of PROM programming at the time. Mine (from eBay) needed a lot of TLC. But it's still the King.

Dial-A-Level

Liquid Level Meter and Controller with Capacitive Probing

This unusual 1970's instrument is a surplus store find. It was initially reversed engineered and repaired thanks to its patents, but we later were able to get in touch with inventor George Rauchwerger, who was super helpful and gave us a copy of the original manual.

HP1607A

Logic Analyzer

With this one, you literally see the ones and zeroes! Made to generate a vector display on an X-Y oscilloscope, this is one of the very first logic analyzers from HP. With about zero memory, but more features than you'd think.

HP4957A

Protocol Analyzer

A very cute machine to debug simple RS-232 serial connections or involved packet networks built on SDLC, HDLC, BiSync, V.21, V.35, ISDN, T1, etc... Supports RS-232, RS-49 and V.35 out of the box. Also has a full VT100 terminal emulation.

HP8444A-Opt 59

1.3GHz Tracking Generator for the HP 8568

This is the special version of the HP 8444A that works as a tracking generator for the HP 8568.

HP 8568B and HP8444A-Opt 59

1.5GHz RF Spectrum Analyzer

My HP 8568 has the dreaded YTO unlocked error.

HP 8082A Pulse Generator

1ns Rise Time Pulse Generator

This awesome pulse generator had many faults, one of which necessitated to remake an replacement for a failed ECL IC.

HP 8662A

10KHz-1280 MHz Synthesized Signal Generator

My 8662A, the fabled gold standard of synthesized low-noice oscillator, is in trouble. Let's fix it.

HP 59401A

HP-IB Bus Analyzer

An early and specialized logic analyzer and generator for the HP-IB bus. It has a delightfully intuitive and direct interface, with one clearly labeled switch and one LED for everything. No cascaded menus in this one, it's all in front of you on the panel, just a blink or a toggle away.

HP 85645A

26.5GHz tracker for the HP 8566

Although I had previously made my own homebrew 2.5GHz tracker for the HP 8566, I eventually bought the real thing that covers the whole band and then some. Which promptly failed on me, and led to quite a switching power supply repair adventure.

Tektronix 7854

Wide Bandwidth Oscilloscope Repair

This is the vintage 'scope and repair that began the collection. This is a legendary and famously expensive instrument. This is the first scope capable of 10 GHz bandwidth that I ever laid my hands on, at the beginning of my career at Bell Labs in the early 1990's.

The following pages have not been completed yet. In the meantime, they just link to the corresponding video or playlist. Contact me if you need more info about the following restorations, that might give me enough incentive to complete the page!