A Fubsy Polymath subdomain

Test Equipment

Vacuum-tube testers, VTVMs, signal tracers, oscilloscopes — owned, in service, on the bench.

Deep-dive volumes arrive as instruments work their way through the queue.

Photo: IDS-2074E oscilloscope + signal generator on the bench by Mortymore · CC BY 2.0

CRT testers

Electrostatic CRT Tester — Mark 2

Electrostatic CRT Tester — Mark 2 The Electrostatic CRT Tester — Mark 2 is a simple, manually-operated bench instrument for testing electrostatic-deflecti… · Owned (DIY-built) · Active deep-dive target · Modern DIY (open-source kit, sgitheach.org.uk; tests tube-era CRTs from the 1930s onward) · Deep dive · 8 vols Live

Curve Tracers

Curve Tracers — Overview & Primer

Curve Tracers — Overview & Primer A curve tracer is a test instrument that sweeps voltage across a device under test while measuring the resulting current… · Reference · Active deep-dive target · Reference (spans the vacuum-tube era through modern DIY) · Deep dive · 5 vols Live

Heathkit IT-3121 Curve Tracer

Heathkit IT-3121 Curve Tracer The Heathkit IT-3121 (and its identical-but-for-color-and-price twin, the IT-1121) is Heathkit's late-1970s semiconducto… · Aspirational · Active deep-dive target · Vintage Heathkit (1970s — transistor / semiconductor curve tracer) · Deep dive · 4 vols Live

VBA Curve Tracer

VBA Curve Tracer The VBA Curve Tracer is Paul Versteeg's open DIY semiconductor / component curve tracer, documented on his blog at paulv… · Aspirational · Active deep-dive target · Modern DIY (2022 — Paul Versteeg "paulvee" open design) · Deep dive · 4 vols Live

eTracer

eTracer The eTracer is a PC-controlled, pulsed-HV vacuum-tube curve tracer / tube tester designed and sold by Chris Chang of Ess… · Owned · Active deep-dive target · Modern commercial (2017 — Chris Chang / Essues Co., Ltd., Taiwan; an independent competitor to Dekker's uTracer, not a member of that line) · Deep dive · 6 vols Live

uTracer NXT

uTracer NXT The uTracer NXT is Ronald Dekker's next-generation DIY tube curve tracer — a modern redesign of the long-running uTracer… · On order · Active deep-dive target · Modern DIY (2020s — next-generation successor to the uTracer3+/uTracer6) · Deep dive · 5 vols Live

uTracer6

uTracer6 The uTracer6 is Ronald Dekker's kilovolt-class DIY tube curve tracer (dos4ever.com) — a distinct high-voltage model in t… · Owned · Active deep-dive target · Modern DIY (~2019–2020 — Dekker's high-voltage uTracer model, 0–1000 V / 1 A; a distinct model from the uTracer3/3+, sold in parallel with the current-mainstream uTracer NXT) · Deep dive · 6 vols Live

Function / signal generators

Gigatronics 6060A Signal Generator

Gigatronics 6060A Signal Generator The Gigatronics 6060A series (6061A / 6062A) is a pair of synthesized RF benchtop signal generators — full ATE-class iro… · Owned · bench-only · Vintage (Fluke 6060A-series design, early 1980s; Gigatronics rebadge ~1995; line discontinued 2013) · Deep dive · 3 vols Live

Multimeters

Simpson 260 Series 8

Simpson 260 Series 8 The Simpson 260 is the iconic American analog VOM — patented 1936, first shipped ~1939, and still in production today (2… · Owned · Active deep-dive target · Vintage-through-current VOM (Series 8 ≈ mid-1990s onward; the 260 line runs from the ~1939-shipped original — patent 1936 — and is still in production in 2026) · Deep dive · 6 vols Live

Power supplies

Heathkit IP-32 HV Power Supply

Heathkit IP-32 HV Power Supply The IP-32 (1962–1967) is Heathkit's regulated tube-circuit lab supply: simultaneous 0–400 V B+ (100 mA continuous, 125 m… · Owned · Active deep-dive target · Vintage Heathkit (1962–1967; all-tube-regulated HV bench supply — 2×6L6 pass + 6BH6 + 2×0A2; replaced by the IP-17, descended from the PS-4) · Deep dive · 6 vols Live

Heathkit SP-2717A HVPS

Heathkit SP-2717A HVPS The Heathkit SP-2717A (1982, Heath-Zenith era) is the later, solid-state-reference generation of the same Heath regulate… · Owned · Active deep-dive target · 1982 Heath-Zenith (solid-state-reference generation of the IP-32 family; 2×6L6GC tube pass + 6AU6 + 10-zener reference + all-silicon rectifiers). Same 0–400 V/100 mA as the IP-32, not higher-current. · Deep dive · 6 vols Live

Signal tracers

PACO Z-80 Audio-RF Signal Tracer

PACO Z-80 Audio-RF Signal Tracer PACO's Z-80 is a classic audio + RF signal tracer for tube-era radio and TV servicing. Two probes — an RF/IF demodulator… · Owned · Active deep-dive target · Vintage (~1950s–60s — Precision Apparatus Co. / PACO branded signal tracer for radio/TV service) · Deep dive coming Live

Specialty test gear

Radio Shack 43-114 Telephone Tester

Radio Shack 43-114 Telephone Tester The Radio Shack 43-114 is a budget POTS line tester for 2-wire analog phone lines. Useful for: verifying tip/ring polari… · Owned · Active deep-dive target · Late vintage / consumer-tier (1980s–90s — POTS / 2-wire analog telephone line tester) · Deep dive coming Live

Tube testers

Heathkit TT-1 Tube Tester

Heathkit TT-1 Tube Tester The Heathkit TT-1 (~1959–60, a kit) is Heathkit's flagship dynamic tube tester — a true mutual-conductance (Gm) tester: … · Owned · Active deep-dive target · Vintage Heathkit (~1957–1965 — Heathkit's top-of-line mutual-conductance tube tester) · Deep dive · 6 vols Live

Supreme Instruments 385 Automatic Tester

Supreme Instruments 385 Automatic Tester The Supreme Instruments Model 385 Automatic (1935, $77.95, Supreme Instruments Corp., Greenwood, Mississippi) is a Depre… · Owned · Active deep-dive target · Vintage (mid-1930s — pre-WWII tube tester, emission-style, with the famous Supreme 'Automatic' switch setup) · Deep dive · 6 vols Live

Variacs / autotransformers (bench infrastructure for tube and mains-powered work)

B&K 1653A Variac

B&K 1653A Variac The B&K 1653A is the bench Variac used to safely re-energize vintage tube gear after long storage. 0–150 Vac output at u… · Owned · Active deep-dive target · Modern (B&K's still-current 0–150 Vac, 2 A bench Variac with a built-in isolation transformer, fuse-protected output, and a single dual-function analog meter — no GFCI; that, plus dual outlets and a leakage tester, is the 1655A) · Deep dive · 6 vols Live

Voltmeters

B&K Dynamic 375 VTVM

B&K Dynamic 375 VTVM B&K's Model 375 — correctly the "Dynamatic 375" (the folder name says "Dynamic"; that's a scaffold typo) — is a 1961 vac… · Owned · Active deep-dive target · Vintage tube VTVM (introduced 1961; 12AU7 + 6AL5, selenium B+, rotating "Dynamatic" drum scale). NOT solid-state — the FET B&K is the later Model 277. · Deep dive · 6 vols Live

Radio City Products 665 VTVM

Radio City Products 665 VTVM The Radio City Products 665 is a mid-1940s combined vacuum-tube voltmeter, ohmmeter, capacity meter, and insulation test… · Owned · bench-only · Vintage (Radio City Products Co., New York; period-dated October 1944) · Deep dive · 3 vols Live

Simpson Model 311-2 VTVM

Simpson Model 311-2 VTVM Simpson's 311-2 (© 1966, the PCB revision of the © 1958 Model 311) is the bench VTVM counterpart to the B&K Dynamatic 37… · Owned · Active deep-dive target · Vintage VTVM (1960s — late-production all-tube or hybrid VTVM) · Deep dive · 6 vols Live