Hum and grounding

[Jack_H]

I am building a Strat with tremolo, but with the ground wire connected to the tremolo claw there's still a hum. When I touch the claw the hum stops. Logically the wiring is correct and my body is acting as ground.

Is this a case of not enough material on tremolo claw for grounding? Am I missing something?

 

[jhamnett]

Do you have a digital multimeter to confirm the ground links? Could there be any coatings on the components that are preventing the ground extending to the strings?

 

[mayfly]

Don't know your exact situation, so take this free advice for what it's worth

With electric guitar, the hum is always coming from your body. Your body acts as a antenna/capacitor and picks up all kinds of EMI hash from lights, computers, phones, etc. When that happens your body starts radiating that EMI back to the environment. Grounding your body drains that capacitor and you stop radiating EMI.

With a typical electric guitar, the guitar is mostly picking up you. But, with the bridge / claw / whateveryougotthat'sconnectedtothestrings grounded, you become grounded when you play the guitar. This is what touching the trem claw does: it grounds you - you stop emitting that stored up EMI.

So, your situation sounds about right from where I'm at. If in doubt, try grounding your body by touching something else (the amp or something) and see if the hum goes away then as well.

 

[Jack_H]

Thank you mayfly. Funny thing as I turned off the amp the hum stopped when I touched the metal switch, so your assessment was correct.

I've always thought my body was the ground, and not source of EMI.

 

[mayfly]

I've always thought my body was the ground, and not source of EMI.

Nope - it's quite the other way around.

 

[Hodgo]

It would be shocking if you were the ground!

Your body is a big sack of water that does a great job acting as an antenna. It actually works both ways: if you’re ever hunting for your car in a parking lot, you can hold your key fob under your chin and it will increase the range while making you look like a lunatic.

 

[AleForce1]

It would be shocking if you were the ground!

Your body is a big sack of water that does a great job acting as an antenna. It actually works both ways: if you’re ever hunting for your car in a parking lot, you can hold your key fob under your chin and it will increase the range while making you look like a lunatic.

Also works for making your fruity pebbles tasty fruitier.