The uTracer6 is the current generation of Ronald Dekker's DIY tube curve tracer (the refined successor to the eTracer). The defining technique is the same: instead of continuous DC at the test plate (which forces a massive supply and limits the test envelope to the tube's continuous dissipation), the uTracer pulses HV into the tube for tens of microseconds while sampling Ip — letting it sweep across the full transfer characteristic, well above continuous Pa max, without damaging the tube. Host-side software runs on Windows; output is curve plots + SPICE models.
Paired with the eTracer on the bench, this is the deep-characterization side of the tube-test workflow — Heathkit TT-1 (Gm go/no-go) and Supreme 385 (emission go/no-go) handle quick triage; the curve tracers produce the data that goes into published SPICE models or matched-pair selection for audio amplifier output stages. The uTracer6's extended envelope vs uTracer3 is meaningful for sweep-tubes (beam-power 6L6 / KT88 / KT120 family) where uTracer3 ran out of plate-voltage headroom.
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.