Biasing after a tube change
Why a matched pair still needs voltage and current checked in the actual amplifier.
Resources
Amp Resources
Practical tools, bench notes, repair resources, build notes, and parts for tube amp techs, builders, and players.
Tool
Tube Bias Calculator
Estimate fixed-bias and cathode-bias operating points, target current, and plate-dissipation percentage.
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Repair Resources
Practical guidance for common tube amp symptoms, safety issues, maintenance decisions, and restoration planning.
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Build Notes
Hand-wired amp examples, circuit choices, board layouts, and build details from the Moddjobbs bench.
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Parts & Boards
Vintage-style fiberboards and tube amp parts for builders, restorers, and working techs.
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Notes worth turning into full writeups.
This section gives future repair stories and technical posts a clear home. For now, it points readers toward the practical topics that will become deeper bench notes over time.
When not to power up a vintage amp
Old electrolytics, two-prong power cords, and unknown service history are warning signs, not mysteries to test at full voltage.
Fiberboard layout matters
Lead dress, ground paths, and service access matter as much as component quality in a reliable hand-wired amp.