Help a nOOb with multimeters

Re: Help a nOOb with multimeters

ok... apparently now all the grounds are giving me 1's and the hots are giving me between 4 and 5. They were giving me 0's for the ground yesterday.... I'm trying a different multimeter cuz I think this one has to be screwed up. It'll act one way one minute and a totally different way the next

Anywho, even if the grounds and perfectly 0, that still doesnt explain why the guitar would suddenly give out no sound. It's worked fine and I've never had a problem with output before, so even if it isnt 100% grounded perfectly, it should still give out SOMETHING
 
Re: Help a nOOb with multimeters

Yeah I'll be sure to do that when I get home. Usually when I take pics of any kind of wiring thing inside one of my guitars, the pics turn out very blurry, and very messed up from the flash. But I'll turn off the flash to see if that works; theres gotta be a decent way to take em. I'm at school right now, so I'll get to that later when I get home.
 
Re: Help a nOOb with multimeters

Ok, I'm probably going to get the pics up tomorrow (assuming they turn out alright), but in the meantime: does anyone have ANY ideas to what it might be or has anyone ever experienced anything this before? I'm headed to Guitar Center friday, do you think it'd be a decent idea to pick up an output jack and switch 'em out to see what happens? I need a metric one right?
 
Re: Help a nOOb with multimeters

Did you turn your volume knobs on? Lol it's happened to me.

Also make sure that the problem isnt in the amp or effect chain. If a pedal is broken or the amp is messed up ull never figure it out poking around in the guitar. Also check around the 3 way switch.
 
Re: Help a nOOb with multimeters

yep, volume on. Tone on full (which is VERY rare for me) jsut for testing purposes. It's not the amp of the signal chain (straight cable from guitar into amp). The amp works with my other guitar perfectly fine.
 
Re: Help a nOOb with multimeters

Ok, I tried taking some pics, but they all turned out very blurry and I couldnt get a decent close up shot were you can actually see stuff. But I did grab a better multimeter and took readings everywhere: (using the setting with the inverter sign)

All pots to one another read 0
From the hot point on the output jack to the "middle lug" of the 3-way hot is 001
The same as above, but with grounds is 001
Then I went through the inside circuit just as the currents flow from the pickups to the switch and got:
Between Two hot lugs on the neck volume: 005
Going from the first Neck volume lug to the hot lug on the tone pot: 001
Between the two lugs on the neck tone pot: 1
Going from the neck volume output (2nd lug) to the switch: 001
And I got the exact same readings for their respective parts for the bridge circuit too

Does this tell anyone anything? If not, if someone could instruct me on how to take good very close-up pics of the inside circuit, I'd be more than happy to post pics
 
Re: Help a nOOb with multimeters

Use as much natural light as possible open all the windows and also turn on all the lights for best results go out side midday and take pictures so that your shadow does not interefere with lighting. If you cant go outside try using a lamp or flashlight but a flashlight might be too concentrated, oh and also dont use the flash.
 
Re: Help a nOOb with multimeters

I fixed the flashing and brightness problem, but I just can't get ANY of my cameras to take a good close-up so that way you can really see the solder joints well. They all turn out as blurry mush. From looking at it, the only joint thats really questionable is the ground joint on the output jack. But I just can't see it suddenly going out one day after it's worked forever.
 
Re: Help a nOOb with multimeters

From the hot point on the output jack to the "middle lug" of the 3-way hot is 001
The same as above, but with grounds is 001

What do you mean same as above IF you mean the Hot output to the ground is 001 then thats the problem, because that would mean your hot output is grounded. If you mean the middle hot lug of the 3-way to ground is 001 then that is bad also because you dont want a connection that is hot to ground being zero that means they're connected and of course means its a short.
 
Re: Help a nOOb with multimeters

I meant that from the ground lug of the output jack to the ground lug of the 3-way switch is 001

On a different note, I took the rest of the stuff you typed and went and check the readings from hot points to all of the ground points (I didn't think of this before). Here is what I found (I think this is the problem, but don't know how to fix it. I still don't think re-soldering everything is necessary because all solder joint cant just magically one day stop working right. It's got to be a hardware part somewhere that just gave out it's sound connection a la output jack.)

Bridge
From first hot lug on the volume pot to all of the back of the pots and the ground lug on the 3 way = 006
From the first hot lug on the volume pot to the ground lug of the output jack = 006
From the first hot lug on the volume pot to the middle lug of the bridge tone pot = 1 (which means no reading I think because it reads 1 just turning the meter on)

From the middle hot lug on the volume to the pots and ground lug of the 3-way = 001
From the middle hot lug on the volume to the ground lug of the output jack = 001
From the middle hot lug on the volume to the middle lug of the bridge tone pot = 1 (or no reading)

Neck
First hot lug of the volume to all pots and the ground lug of the 3-way = 004
First hot lug of the volume to the ground lug on the output jack = 005
First hot lug of the volume to the middle lug of the neck tone = 1 (or no reading)

Middle hot lug of the volume to all pots and the ground lug of the 3-way = 001
Middle hot lug of the volume to the ground lug of the output jack = 005
Middle hot lug of the volume to the middle lug of the neck tone = 1 (or no reading)

Keep in mind that at the exact moment I was playing as it was going out, the output jack was loose and the more I wiggled it, the more it cut in and out.



Give anyone any ideas?
 
Re: Help a nOOb with multimeters

hots to grounds shouldn't be giving 0s they should be very high close 1 which is the multimeter basically saying infinite. If your volume knobs are turned off that sends the hot to ground so that might be why your getting those readings or maybe your pots are broken. And yes solder joints can become bad as they corrode. If there was an air pocket in the solder joint it could corrode it from the inside and you wouldnt be able to tell. So just check everything. You should be using the beeper setting. Cause when you use the resistance thing between the hot and ground then your basically taking the resistance of the pickup (atleast when i do it thats what happens.)
 
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Re: Help a nOOb with multimeters

I have all my pots on 10

The solder joint on the ground lug for the output jack looks HORRIBLE. It's VERY dull and has black junk all around the base of it and stuff that looks like dried molasses. Could a bad solder joint there cause any of these problems?

And it isnt a beeper setting. I thought it was supposed to be because thats what MetalBlaze (i think it was him) told me to use back on the first page. It's the inverter symbol.
 
Re: Help a nOOb with multimeters

well since connecting hots to grounds give me those "not should be" readings, what can I do to correct em without having to re-solder everything thorough again and starting over? Surely not all 4 pots went out and the exact same second, so that can't be. The 3-way looks alright and still flips nicely. And I have heard that it's a good idea to automatically change out the output jack after buying an Epi guitar
 
Re: Help a nOOb with multimeters

The first I thought from your discriptions is to try new pots. Also as GuitarManMike suggested it could be some bad solder joints as well. But to be sure try changing the pots.

The beeper setting is the one with the diode symbol (looks like an inverter but it's a diode ;)).

If I think of any more useful ideas I'll jump in again. ;)
 
Re: Help a nOOb with multimeters

While on the subject of mutli-meters:

To make things easier to test, I have alligator clips clipped on the ends of my multi-meter probes. That way I can attach the other ends of the clips to the PU wires, and not be fumbling, or get variable readings because the contact isn't quite firm.
 
Re: Help a nOOb with multimeters

The first I thought from your discriptions is to try new pots. Also as GuitarManMike suggested it could be some bad solder joints as well. But to be sure try changing the pots.

The beeper setting is the one with the diode symbol (looks like an inverter but it's a diode ;)).

If I think of any more useful ideas I'll jump in again. ;)

well thats the setting I'm using, and it hasn't beeped once since I started testing (I'm using a different, much better quality multimeter since you last responded). Does that mean the whole thing is shorted?

And is there anything to try before changing all of the pots? I really hate to dump the 30 or 40 bucks to get new pots and come to find out that there they weren't the problem and that the old ones were perfectly fine.

How about the for an idea? Will a luthier be able to figure out the problem? I probably need to take it to one anyways because the 11th fret needs slight filings down and the truss rods need adjustment (and I've never done that before and with my luck, I'd snap the neck in half). I'm going out of town next weekend and can't play it in the meantime anyways so I wonder if I should just do that. Luthiers do electrical work like that right?
 
Re: Help a nOOb with multimeters

Yes they do that kind of work. Then yes, it's better to get advice from a luthier then. I'm sorry I can't be of any help here, bro.

You can just take the pots off and measure them with the multimeter to see if they are ok. You can set it to measure Ohms in the right scale, connect the probes to one of the outer and the middle lug and turn it. You should see the value going from 0 to whatever the value of the pot is.

The multimeter should beep if you have a short. Hmmm that thing about not beeping it's quite strange actually. What about if you touch its two probes to each other?

That setting has the diode symbol and it's supposed to be for testing diodes (diodes should be shorted when test them in the right polarity and when you reverse the probes should be like open circuit), hence the beep function to make the testing easier.
 
Re: Help a nOOb with multimeters

Well I'll just take it to him then.

And I touched the two probes together, and it still didn't beep

As for testing the pots with the probes, I used the 200K setting and I got a sweep from 0.00 to 13.8. Thats not right is it? This was on the volume that is an audio taper 500K
 
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