• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

how to test...

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OK built k16ls amp. only makes a very little sound. Ya'll say to check voltages. OK...this makes me sound stupid but here goes.
Do I use multimeter black to board ground and red to where I want to check voltage? and do I need to leave tubes in when I do this. For instance, Checking Hi voltage side. Black to board ground and red to test point = correct reading ?
Not reall that stupid, just don't want to short anything or make my problem worse. Not very versed in component testing.
 
Jeff: You should continue this discussion on your existing thread.......

First, a couple of points.......when a multimeter is set to check voltage, it has very high impedance so your meter will not "short" anything (unless you slip with the probe and short something by having the tip touch 2 components at once).

In general, connecting the black (common) lead of your meter to ground (like your ground stud) and connecting the red lead to various components to check voltages is how it's done. You can also check voltages across components by simply connecting the leads across the component in question. Remember, when set to measure voltage, your meter high very high resistance so it won't short anything.

If you are using your meter in current mode, it has close to zero impedance and is meant to be put in the circuit, that's why you usually have to move the leads to different spots on your meter when measuring current. You rarely need to use this mode to test your amp.

To start with, test the amp with the tubes in, we'll let you know if you need to remove them for other tests.

You need to determine if your amp's DC voltages are correct to start.

Finally, have you read the safety sticky on this forum? You don't want to probe a live tube amp using both hands as you have the possibility of taking high voltage across your chest if you screw up. Always use one hand.....typically with black lead connected to ground.....or better yet, get some clip leads for your meter so you can test hands-free' that's what I do.
 

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