DIY Tools - DiMastro GTA

All DIY Tools

Each one walks through the actual build — parts, wiring, construction steps, and how to use it safely — not just the theory behind it.

DIY instructions for building safe, accurate bias-testing probes.

Build a dim-bulb tester to safely bring up an amp for the first time.

A portable discharge stick to bleed filter caps down by hand before you open a chassis.

A non-inductive resistive load for testing an amp safely without a speaker.

Two cheap, battery-powered tools that together find exactly which stage of a dead or noisy amp stopped passing signal.

The same fault-finding pair built from parts you likely already own — a powered speaker, a phone, a cap, and a resistor. No IC circuit to build.

Adjustable bias trim pot mod — get a basic in-amp g_m tester plus proper per-tube biasing, from the same change.

Coming soon: more hand tools for the bench.