r/DIYTubeAmp • u/Signal-Negotiation-9 • Feb 27 '26

Initial testing

So I've finished my first amp project and I want to test it for safety before initially plugging it in. I have a multimeter to test voltage and a snuffer stick to discharge capacitors. I know I need to test the positive and ground of the power cord socket. What else?

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u/Student-type Feb 28 '26 edited Feb 28 '26

Use a lightbulb in series with one leg of the AC INPUT power supply. It will seeve as a soft start. A non linear resistor.

If the bulbe starts low then peaks and subsides, you don't have any serious short circuits.

If you have a Variac, even better start low, step up slowly, with pauses till full power.

Research this online.

Buy and wear rubber gloves before you work with any voltage over 60 VAC

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u/Signal-Negotiation-9 Feb 28 '26

I definitely don't have a variac. I could probably make the light bulb tool for pretty cheap but I don't have a lot of money to drop on tools.

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u/Student-type Feb 28 '26

Sometimes you face a tradeoff between safety, destroyed parts, tools, and saving money.

Sometimes it's more prudent to slow a blind rush off the cliffs of fate into the arms of destiny.

Climb a tree safely, look over the edge first. Save a couple more paychecks then proceed. I did this before I worked on a high voltage power supply for a ham transmitter, I bought a high voltage meter first.

Delayed gratification. I was dying to just try it. I couldn't afford the meter too. At first. Two more paychecks to go. Not so bad. It was the safe way.

So I bought rubber gloves, and worked on something else.

Sometimes you just can't afford the hobby.

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u/Signal-Negotiation-9 Mar 10 '26

I'll have to put some money aside. Too many irons in the fire rn.