How we work

Specs and history

We checked everything on each model page (years made, bandwidth, digits, ranges, interfaces, options and the stories behind them) against sources we could cite. Those include the makers’ own manuals, datasheets and history pages, the TekWiki, the HP Memory Project and dealer spec pages. When we couldn’t confirm a detail, like an exact year or a part number, we left it out or wrote it loosely. Instruments this old had running changes and option codes, so use every page as a starting point and check the unit itself.

No guessed prices

We don’t publish price ranges from memory. A price shows on a model page only when it comes from a dated snapshot of that model’s eBay listings (more below), and it always carries the date we checked. Asking prices aren’t selling prices. Before you make an offer, look at eBay’s sold listings (filter to “Sold items”) for the exact model and base your offer on those.

Finding listings

Models without a snapshot link to a plain eBay search for the exact model. Bench gear turns up in more than one eBay category, so the search runs across all of eBay. Expect some manuals, probes, knobs and parts boards in the results, and skip them.

Condition first

Old instruments wear out in predictable ways. Capacitors dry out, fans seize, CRTs dim or burn, battery-backed memory loses its calibration data, input fuses blow and front-panel parts snap off in shipping. The checklist on each model page covers what to look at in the listing and what to ask the seller, and our guide to checking used test equipment goes deeper. We want you to pay the right price for what a unit really is, including the work it needs.

Product photos

The big photo on a model page and its cards is a representative image, not a photo of any instrument for sale. We make it with an AI image model from several real seller photos of that exact model, then compare it with those photos before we publish. Every model gets the same plain studio backdrop so they look consistent side by side.

So the photo shows what the model looks like, not the condition of any one unit. Badges, options, knobs and wear vary from unit to unit, and some small details may be simplified. Judge condition and completeness from the seller’s own photos, and ask for a photo of the screen after power-on before you buy. Wherever a representative photo appears large, it carries the caption “Representative photo, made by AI from real seller photos. Every listing differs.” Models without one show no photo.

Market snapshots and picks

For each model with a buying guide, we go through the matching eBay listings on one date. We record how many there are, the price range, where most asking prices sit, and a set of listings with their price, shipping, format, seller feedback and condition. The date sits next to the listings, and by the time you read it some will have sold or ended. The “See every listing on eBay” link always opens the live search. When a snapshot has listings, the model’s typical price on the page comes from it. When nothing was listed, the figure is labeled an estimate.

Then we tag the listings worth a look. Cheapest is the lowest delivered price for a complete, working unit. Best value is a unit with some evidence it works, at a below-typical price. Best for beginners and Easiest to get working go to units that are tested or shown working. Collector’s pick is a sought-after version at a sane price, and Project piece is a cheap unit worth fixing. Two warning tags flag listings to approach with care. Check the seller means little or no feedback, and Priced high means well above the typical range with no clear reason. These are judgment calls from the listing text and photos. We haven’t had the instruments on our bench, and nobody pays for placement.

Independence

No affiliate links. We earn nothing (see the disclosure). We’re not paid by sellers and we’re not affiliated with any instrument maker. We run no analytics or tracking cookies.