The Simpson 260 is the iconic American analog VOM — in continuous production from 1936 (the original 260) through the early 2000s (Series 8 / 8P). The **Series 8** is the late-production revision with improved overload protection, the modern lever-style range switch, and the taut-band meter movement. 20 kΩ/V on DC, 5 kΩ/V on AC. For tube-circuit work it's loadable on high-Z nodes (always reach for the [B&K 375](../B%26K%20Dynamic%20375%20VTVM/CLAUDE.md) or [Simpson 311-2 VTVM](../Simpson%20Model%20311-2%20VTVM/CLAUDE.md) on grid / screen / AVC measurements) but on power-supply rails and filament circuits the 260 is the right tool — fast, no warm-up, no batteries to worry about for voltage ranges.
Generations of US Navy, Bell System, and military techs were trained on the Simpson 260. Knowing how to read it — the mirror scale, the cascaded scales, the reciprocal-ohms scale — is part of the basic literacy of vintage electronics work. The Series 8 is the version most likely to still be serviceable today (parts availability for the earlier Series 5 / 6 movements is much thinner). Common service issues: the rotating range-selector wafer contacts oxidize; the 1.5 V D-cell holder corrodes; the AC rectifier (copper-oxide on early series, silicon on Series 8) ages.
A multi-volume deep dive on this instrument is in planning. When the first volume lands in the source project's 02-inputs/volume_sources/, this page upgrades automatically — no website code change required.