Need some help understanding grounding stuff etc.

[devilfish]

hi,

i recentyl; realised (not knowign much about electrocis in general) i have no idea what is grounded inside a guitar and why it i9s all grounded?

if sopmeone could explain this is a bit of detail but so i can understand (not very complicated )

i dont really uneerstand also, why the sheilding paint inside my fender sdtrat is grounded....it has a little screwn connected to the paint for some reason...why does this need to be grounded....where is it grounded too?

thanks

[devilfish]

anyone...i need some help here

[Metalblaze]

The guitar by itself is not grounded. It is just wired in a way that when it gets plugged to an amp it's grounded to the amps ground. The job of the jack is to transfer the signal and to connect the amp ground to the guitar spots that need to be grounded.

As for shielding, it needs to be grounded to isolate the circuit from interferences, so that every unwanted signal coming from other frequencies around will be sent to ground (the signal cemetery haha).

I hope that helps.

[devilfish]

hi,

so when following schematic etc. as long as all the wires that end up going to the output jack get there does it matter how they get there?

as in, if i didnt want to solder to the back of the pot...would the alternative be to just laink all the wires together and send them to the output jack?

also, to shield the cavities in a guitar, baring in mind i already have the copper tape adhesive stuff...asll i need to do make sure that a wire gets connected toa bit of the foil and end up to the output jasck? my strat ahs the cavity paint and it has a screw with a wire going to the pot that then ends up at the output jack...is this what i should do with the cavity copper foil stuff?

thanks

[Metalblaze]

It doesn't matter how they get there (there=the ground lag of the jack, not he hot one ). The back of the pot is a spot that must be grounded....I think....let me check it.

[Metalblaze]

The back of the pot is a spot that must be grounded....I think....let me check it.

Erase that. Actually yes, you can let them without ground, but it helps when you ground them.

Edit: Imagine the pot as a circuit in a metal case. It always helps to ground the case. Of course they're not RF amplifiers or something like that but it helps.

[devilfish]

hi,

ok yeah, it was just an example. so its basically ANYTHING that can possibly conduct a singal needs to be grounbded. so the copper foil and the back of a scratchplate just need to be grounded, so anything inside the sheilding is protected from signals...is that correct?

So if the sheilding in the cavity and the sheilding on the back of a pickguard make an enclosure, as lng as thats grounded the inside is protected from outer interfierence?

im still a bit unsure as to why some of the pot lugs in the schematics are wired to the back of the pot then to the output jack but im sure i will understand eventually.

any help with wthat will be much appreciated.

thanks again.

[Metalblaze]

so its basically ANYTHING that can possibly conduct a singal needs to be grounbded. so the copper foil and the back of a scratchplate just need to be grounded, so anything inside the sheilding is protected from signals...is that correct?

Yep.

So if the sheilding in the cavity and the sheilding on the back of a pickguard make an enclosure, as lng as thats grounded the inside is protected from outer interfierence?

That's true too.

im still a bit unsure as to why some of the pot lugs in the schematics are wired to the back of the pot then to the output jack but im sure i will understand eventually.


any help with wthat will be much appreciated.

thanks again.

These lugs need to be grounded (so they are attached to the back of the pots) because the circuit works that way. You need to connect the 3rd lug of the volume pot to ground for example because this is the only way you can turn off your guitar (zero volume), leading the guitar signal this time to ground.

No problem!

[devilfish]

hi,

thanks so much, i hate knowing HOW to do something if i dont uderstand why im doing it.

are there any websites/books you have where i can look at for a reference in future, rather than asking lots and lots of questions if its only a 1 line answer and in a book or something. where did you learn it all from?

thanks very much

[Metalblaze]

I studied them for 6 years and still doing so, hehe. But there are good sites that help a lot.

I think the most popular is: http://www.guitarelectronics.com/
and some others I would look (google surfing):
http://www.projectguitar.com/tut/tutorial10.htm
http://www.fretnotguitarrepair.com/E...nicsRepair.htm
http://www.guitarnuts.com/index.php

[caprae]

A poster named Noth uses plastic cased pots (and swears by the improvement in sound). You cannot solder to the back of these so he puddles some solder onto the copper shielding tape and grounds everything to that puddle. The pots touch the grounding tape when they are inserted into the guitar and are grounded that way, if I recall correctly.