Right room for tech prob?

[Stevie M]

Hi Guys.
I don't know if this is the right room to ask this, but a mate has had a slight slight shock prob.
He got a s/h Marshall amp, and a was given a really cheap strat copy. He's played the guitar a few times through it, no probs, but suddenly got a fairly hefty jolt. He's also got a les paul copy that's no problem playing through the same amp, which leads me to think it's a guitar prob rather than the amp?

I had a look at the wiring on the strat, everything seems to be ok---no loose wires etc etc.
I suppose what I'm asking is, is it possible it's an intermittent amp fault that only happens on one guitar, or likely defo the guitar?
Oh yeh---there's more of a Hum on the cheapo than the les paul as well.

This is in the UK, with 3 pin mains plug, and plugged into the same socket at home.

Cheers.

 

[LesStrat]

Re: Right room for tech prob?

Probably an Amp Room question, but we're pretty loose about such things. Especially when the question crosses areas.

I'm sure the techies will be along shortly.

 

[GoldenVulture]

Re: Right room for tech prob?

Amp problem. There should be no voltages on the guitar that are any where near shock capable. Was he touching [ grounding with ] anything else when he got the shock ? it could mean that there is bad earthing in the amp or a faulty component that's letting high voltage leak into the amp some where.

PS; This thread would usually go in the Amp room. You could ask a mod to move it for you.

 

[jeremy]

Re: Right room for tech prob?

its an amp issue, not the guitar.

ill move this to the amp room

 

[Stevie M]

Re: Right room for tech prob?

Thanks guys.
My 1st thought was Amp prob, but it threw me a bit when it only affected 1 guitar.
Weird? Unusual??

 

[ericmeyer4]

Re: Right room for tech prob?

I'm assuming that with the 3 pronged plug one is a ground?

Were you able to check the ground wire is correctly connected? It should be pretty easy. Unplug the amp, touch a multimeter prong to the amp's ground that would go to the wall and a place where it is grounded on the chassis. If the meter beeps (assuming you meter does) you should have a good ground and can likely start to rule out the amp.

It might be one of those things where the cord is worn and there is a slight break in the connections so it is only grounded some of the time.

I would also check the wall outlet to ensure it is grounded. I outlet tester is only a few bucks at the hardware store.

I would meter all of your connections on the guitar as well. You can have shiny solder and tight connections, but still have a bad connection. If that makes sense.

 

[Gearjoneser]

Re: Right room for tech prob?

Something like this happened to me years ago. I was standing in a rehearsal room with crappy grounding, or a ground loop occurring on some of the gear. I'd touch the strings, and could feel a slight sting of current. To make sure, I kissed the strings and definitely felt it.

First, I started unplugging everything in the room except for my amp.

To this day, I'm not sure what it was, but it could have been DC leaking from positive to ground through a faulty pot or something??? I really don't remember solving it, although I remember that changing a pot got rid of the hum cancellation I'd hear every time I touched the strings. When I took my hands off the strings, hum would come back. So, I figured the shock had something to do with that, but not sure.

 

[ErikH]

Re: Right room for tech prob?

I had this happen once. Turned out to be a bad wall outlet. Threw my tester on it and it was open circuit. YIKES! Now I don't plug in to any outlet at a venue without checking it with my tester.

Might be a good idea to check the outlet wiring where your buddy is plugging the amp in to as well.

 

[Stevie M]

Re: Right room for tech prob?

I didn't have a lot of time to check it all properly, I'll give it another go soon as I can---some real handy pointers here though:fing2:

Doesn't give give a whole lot of confidence in the guitar though when:-
1--No name at all on it anywhere
2-- The bridge doesn't screw down on the body properly 'cos it's catching on the edge of the scratchplate!

Then again, it was bought for him by his Mum:no:

 

[Left_Hand_Strat]

Re: Right room for tech prob?

I didn't have a lot of time to check it all properly, I'll give it another go soon as I can---some real handy pointers here though:fing2:

Doesn't give give a whole lot of confidence in the guitar though when:-
1--No name at all on it anywhere
2-- The bridge doesn't screw down on the body properly 'cos it's catching on the edge of the scratchplate!

Then again, it was bought for him by his Mum:no:

probably from argos....

but yeah check your wall sockets first mate, just to double check, sounds daft but something sockets actually do wear out and knacker up, so best to make sure.

It could be a guitar issue, I used to get mini tiddy shocks from my squier strat before rewiring it.

However, it could be the amp. Best thing to do, again, is to get your meter out and check certain things inside the amp. I'd also check to see of there are any components in the amp which look like they are bulging, leaking or just look out of the ordinary.

Comeone mentioned the power cord, How old is this amp??

 

[Stevie M]

Re: Right room for tech prob?

Ordered one of those wall socket tester gizmos now, when it turns up I'll do all the checks I can for him, probably rewire the guitar as well unless he wants to sell it and get something different.
Thanks again guys:1: