In the pantheon of electrical engineering, Jim Williams is a demigod. His bench, famously cluttered with soldering irons, coffee cups, and an array of oscilloscopes, was a museum of analog ingenuity. When hobbyists and pros alike search for "Jim Williams" gear, the immediate reflex is to hunt for a B&K Precision 1470 or a B&K 2120—the ubiquitous yellow and blue CRT scopes he famously used to demonstrate switching regulator waveforms.
However, the true connoisseur knows that the B&K scopes were merely the window dressing. The soul of Jim’s work—and the most valuable "purchases" associated with his name—are far more esoteric. If you are looking to buy, collect, or build what Jim actually used, here is the exhaustive list of what you are actually after.
Perhaps the most famous non-B&K item associated with Jim is not a commercial product but a homebrew pulse generator. In his seminal 1991 Application Note 47 (AN-47) – "High Speed Amplifier Techniques", Jim detailed a 1ns rise-time pulse generator built into a tiny tin box.
The Purchase: Today, collectors do not buy this from Jim (obviously), but they purchase vintage Tektronix tunnel diodes (specifically the TD series) and ultra-fast germanium transistors to build clones of this exact circuit.
The Detail: The hunt for original 1N3712 or 1N4153 tunnel diodes on eBay is a direct result of Jim’s literature. Purchasing these obsolete components is effectively "buying a piece of Jim's methodology."
While Jim loved B&K for viewing signals, he trusted Fluke for measuring them. Jim was obsessive about DC accuracy. On his bench, nestled among the chaos, sat a Fluke 731A DC Voltage Standard.
The Purchase: Serious collectors seek out the Fluke 731A (or the later 732A) not for its looks, but because Jim used them to validate the linearity of his custom data converters.
The Detail: Purchasing one of these today is a heavy investment (often $1,500-$3,000 for a calibrated unit). Enthusiasts specifically search for units with "Vintage Calibration Stickers" from the 1980s, hoping to find one that might have passed through the Linear Technology calibration lab in Milpitas, CA.
You cannot calibrate a Fluke without an HP. Jim's bench frequently featured the Hewlett-Packard 3456A 6.5-digit multimeter.
The Purchase: While B&K handled the time-domain (scopes), HP handled the voltage-domain. Collectors purchase the HP 3455A (the older, nixie-tube version) specifically because Jim praised its integrating architecture for removing noise from switching power supplies.
The Detail: The purchase of these units is often accompanied by the purchase of Teflon-insulated test leads and gold-plated banana plugs, because Jim famously despised alligator clips, insisting that thermocouple effects ruined low-level measurements.
If you really want to buy what Jim bought, you skip B&K entirely and look at the Tektronix 576. This massive, heavy transistor curve tracer was Jim’s favorite tool for matching transistors.
The Purchase: Jim didn't just use this to test; he used it to select parts. He purchased dozens of transistors at a time, ran them through the 576, and hand-selected the ones with the flattest beta curves.
The Detail: Today, a "Jim Williams style purchase" means buying a Tektronix 576 and a large bulk lot of 2N3904 or 2N2369 transistors. You aren't buying the tester for the tester; you are buying it for the process Jim documented in AN-55.
Here is where the definition of "purchase" gets nuanced. While Jim sold his time to Linear Technology, he never sold his books directly. However, EDN Magazine and Linear Technology sold compilations.
The Purchase: The "Linear Technology Application Note Collection" (specifically volumes 1 through 4) are prized physical purchases.
The Detail: These are not just books; they are hardbound collections of his prose. More specifically, collectors purchase vintage issues of EDN from the early 1980s. Jim wrote a column called "Circuit Ideas" before he joined LTC. Buying original copies of these magazines is the literary equivalent of buying his early bench notes.
In the late 1990s, Jim worked with Bob Dobkin to create the LTZ1000—an ultra-stable voltage reference chip.
The Purchase: While this is a chip, not a finished product, buying an LTZ1000A is arguably the purest "Jim Williams purchase" you can make today.
The Detail: Hobbyists buy these chips ($50-$100 each) specifically to build the "Ultimate Voltage Reference" that Jim detailed. To make it work, you also have to purchase a custom ovenized PCB and a precision resistor network (Vishay foil resistors), which Jim recommended to keep the thermal drift below 0.05ppm/°C.
Finally, no Jim Williams purchase list is complete without the HP 11500A Active Probe.
The Purchase: Jim famously hated passive probes because they loaded down his switching nodes. He purchased active FET probes to look at the gate drives of his MOSFETs.
The Detail: Collectors today purchase vintage HP 11500A probes and the accompanying Power Supply (HP 11600A) because Jim’s app notes explicitly instruct the reader to "use a low-capacitance probe" to avoid seeing a "ringing artifact" that isn't actually there.
When an engineer says, "I want to make purchases besides B&Ks from Jim," they are rarely talking about a specific store. They are talking about a philosophy of measurement.
You are buying Tektronix for display, Fluke for reference, HP for accuracy, and obsolete semiconductors for execution.
The physical B&K scope was Jim’s canvas, but the purchases detailed above were his paint and brushes. If you manage to acquire a Fluke 731A, a box of tunnel diodes, and a first-edition copy of AN-47, you have not just bought equipment; you have bought into the rigorous, analog-centric worldview of the man who wrote the book on high-speed measurement. The B&K was just the starting line—the real race is in the components, the references, and the paper they were printed on.