You'll find whole labs full of it once in a while on Bidspotter, set a saved-search for some names like Rohde and Tektronix and Keysight and you'll get emails once in a while.

I had the same question. Seems the UC schools use Publicsurplus.com, but last time I looked, I didn't see anything interesting.

I bought it through edispositions.com.

Extremely good deals are rare and the chance that there’s something broken is very real. I often consider that a feature: fixing test equipment is a bit of a hobby, but be prepared to end up with a doorstop that cost a few hundred dollars.

Here are some examples that I bought though them:

- HP 8650E spectrum analyzer: works but intermittent shutdowns

- TDS 794D: works, but CRT is broken. A well know failure mode. Need to install a $75 LCD replacement.

- this R&S AMIQ: totally broken. Needed many days of work to revive.

It’s high risk buying these things.