Tools

Here is a list of tools that a tube amp tech typically uses in the process of building / testing / troubleshooting tube amps in order to get them to peak operation.

Unlike our usual practice of listing items in alphabetical order, we're going to list out the tools in order of technical sophistication. Unless you have tube amps that are multi-channel and have midi functionality, a tech typically only needs rather rudimentary tools.

• Schematic: This is a diagram of the topology of the circuit in the amplifier. Using a schematic is almost always necessary when working on an amp so that the tech can refer to it and understand how the current is flowing through each part of the amplifier s/he is working on.
• Chopstick(s): Wooden (non-conducting) probe (basically a stick) to move wires in an amp chassis to safely help determine signal interferences running on the wires that may be created by the existing in-chassis wiring.
• Capacitor Discharge Jumper: Alligator clips that have been modified with a resistor that are used to drain high-voltage filter capacitors.
• DMM / DVM: Digital Multimeter / Digital Voltmeter
• VTVM: Vacuum Tube Voltmeter
• Signal Generator: Generates a tonal sine wave (a musical note) that is fed into an amplifier.
• Variac: Variable AC Transformer
• Tel-Ohmike TO-10: Capacitor Tester
• Sencore PR57 "Powerite": An isolation transformer for testing possible ground loops - also useful for reforming old electrolytic capacitors.
• Teltronix 422 Oscilloscope: A particular model of oscilloscope we have here at Thermionic Studios
• Teltronix 456 Oscilloscope: Another oscilloscope that we have and probably don't need
• Lightbulb Limiter: A rudimentary "variac" that uses the lumens and wattage of a lightbulb to both limit the amount of current going to an amplifier, and to also indicate when the filter capacitors have "filled" with electrical charge.
• Speaker (Dummy) Load: A resistive network that acts like a speaker and can take an amplifier's full output without generating any sound.
• Bias Probe: Used to measure the bias current to one or more power tubes to make sure that they have been biased to the desired rating.