Help - Problem after installing new Pups!

Scottrw2002

New member
Hello All,

First off please don't fry me for being a noob and messing up, but then we don't learn if we don't try eh!? Get your excuses in early.... ok

I have just installed SD pups in my Epiphone SG G-400. SH-2 at the Neck, SH-4 at the Bridge. I soldered them as per the wiring diagram and whilst not necesarrily the tidiest job in the world, it all looked solid enough. I removed old pups, installed new ones in the same place and didn't mess with anything else. Before re-stringing etc I plugged in and tapped pups with screwdriver tip, all sounded ok. Put everything back together, plugged in and nothing!?? I have tried everything! Was worried I had wired them the wrong way round, so I swapped them - no joy! Swapped back - still no joy!??

I did read something about a cold solder joint someone else had so I tried really getting the exisitng solder moten to get a good connection but still nothing.

I was a bit clumsy with the soldering iron and melted a touch of wire shielding in places but nothing that has gone through to the wire. I'm a bit worried that with all my messing I could have fried everything but Im not sure how to test. I don't have a voltage checker thingy!

So... Can you guys help!? I really dont want to take it to the shop to fix as I'd rather do it myself as I like to tinker (just not very good at it)!

On the plus side, it looks awesome now with my Zebra pups... Just wish I could hear them.. lol :smack:

Thanks for reading

Scott.
 
Re: Help - Problem after installing new Pups!

You know...you just have to have your guitar on your lap...sitting at the pc...and look back and forth from the wiring diagram on the SD site and your guitar. Follow each wire very closely...and make sure all your connections are correct. I've replaced my PuPs a dozen times...and I still make a mistake or 2 occasionally. Its very easy to overlook something in your zeal to play. Pay special attention to your wiring going to the output jack. Something is amiss there...
 
Re: Help - Problem after installing new Pups!

So you don't think I will have fried something in my eagerness then?

The only thing I can see is that on SD the bridge ground comes from the bridge to the bridge volume pot, then to the output jack! I appear to have a thin black wire attached to the bridge volume pot, but it ends there.

Whats confusing me is that it worked with the Epiphone pups. All I have done is to unsolder them and replace with the SD ones!?
 
Re: Help - Problem after installing new Pups!

Any other suggestions folks? After having looked at the diagram again I am pretty sure Im connected properly!! :(
 
Re: Help - Problem after installing new Pups!

Sounds like an output jack issue to me too, especially if you were getting a signal at one point as you describe...:33:
 
Re: Help - Problem after installing new Pups!

P1020109.jpg


Thanks all.....

Pic shows grey wire straight to output jack

the pups are connected green and bare to back of volume pots and black grounded to side terminals. red and white are taped as per instructions.

Nothing else changed.... Any ideas?

Thanks for the response so far!
 
Re: Help - Problem after installing new Pups!

Here's the two things I would look at first:

1. Are those red/white wires actually soldered together? Or are they just taped up? They must be soldered together.

2. If one of those foil shields, or the bare ground wire, touches up against one of those "hot" lugs when you put the cover on . . . you ground out the sound.

Try doing the tap-test with the rear cover off, and with the wires separated a bit. After you confirm the red/white wires being soldered. ;)
 
Re: Help - Problem after installing new Pups!

The red white wires aren't soldered together. So that will make a difference? Ok I will try that, so solder red/white together! I will update ASAP... thanks
 
Re: Help - Problem after installing new Pups!

Yup. That'll do it. If they aren't soldered together, you don't have an electrical connection between the two coils.
 
Re: Help - Problem after installing new Pups!

Ok well that didn't work! There may be an improvement in that there is sound from both pups but it is very quiet! On a distorted channel you can hear them (but they dont sound distorted) on a clean channel you can hardly hear a thing. I tried the tap test and both pickups seem to work, but no volume.

Also I cannot tune up using the electronic tuner on the amp! It doesn't seem to recognise a signal at all!?

I'm beggining to think I have messed this up royally :o(
 
Re: Help - Problem after installing new Pups!

Here's what I would look at next:

Your using shielded wire for most of your connections. Thats good, but . . . shielded wire can be difficult to deal with. Especially if you're a novice at soldering and stripping. Look over all of those connections closely to make sure none of the "foil" or ground sheath is touching up against a "hot point".

Look carefully. Only takes a strand or a flake to mess you up. ;)
 
Re: Help - Problem after installing new Pups!

Only takes a strand or a flake to mess you up

I've just fried two Gibson 300K Pots... with a 30W iron! I just can't believe it!

Unless Gibson parts maker is supplying some chinese-made garbage, I just don't know HOW it could possibly happen using such a low-power iron. I'm shaking my head in disbelief.

Can anybody relate to a similar situation like mine? Or somebody put a spell on me?

Pepe aka Lt. Kojak
Milano, Italy
 
Re: Help - Problem after installing new Pups!

How would I know if I'd fried mine!? I'm guessing I haven't as they are 500k pots!?
 
Re: Help - Problem after installing new Pups!

I've just fried two Gibson 300K Pots... with a 30W iron! I just can't believe it!

Unless Gibson parts maker is supplying some chinese-made garbage, I just don't know HOW it could possibly happen using such a low-power iron. I'm shaking my head in disbelief.

Hey Pepe; The unfortunate reality is that you're far more likely to fry a pot with a low-power iron than a high-power one. Its kinda like how its more likely to blow speakers with too low of power than too much.

Here's whats happening: It takes a certain temperature to melt solder. There's no getting around that. The back of a pot acts as a giant heat-sink. Thats the last thing you want with a low power, unregulated iron. The pot just sits there and slowly absorbs the heat until the whole thing is up to solder-melt temp. (Including the plastic parts inside.)

A high-power, regulated iron, can heat up a "hot-spot" quickly, allowing solder to flow, before the internal components of the pot heat up.

This is why I stress not to solder to the back of a pot unless you have well-regulated, high-power iron.
 
Re: Help - Problem after installing new Pups!

Hey, guy, nobody on this board is gonna dog you for being a noob, or for making a mistake -- everybody was a noob at one time, and everyone screws it up sooner or later. Congrats for making the attempt.
 
Re: Help - Problem after installing new Pups!

Hey Pepe; The unfortunate reality is that you're far more likely to fry a pot with a low-power iron than a high-power one. Its kinda like how its more likely to blow speakers with too low of power than too much.

Here's whats happening: It takes a certain temperature to melt solder. There's no getting around that. The back of a pot acts as a giant heat-sink. Thats the last thing you want with a low power, unregulated iron. The pot just sits there and slowly absorbs the heat until the whole thing is up to solder-melt temp. (Including the plastic parts inside.)

A high-power, regulated iron, can heat up a "hot-spot" quickly, allowing solder to flow, before the internal components of the pot heat up.

This is why I stress not to solder to the back of a pot unless you have well-regulated, high-power iron.

+1 That's why I finally bought a Hakko soldering station with a variable temp control.
 
Re: Help - Problem after installing new Pups!

Here's whats happening: It takes a certain temperature to melt solder. There's no getting around that. The back of a pot acts as a giant heat-sink. Thats the last thing you want with a low power, unregulated iron. The pot just sits there and slowly absorbs the heat until the whole thing is up to solder-melt temp. (Including the plastic parts inside.)

A high-power, regulated iron, can heat up a "hot-spot" quickly, allowing solder to flow, before the internal components of the pot heat up.

This is why I stress not to solder to the back of a pot unless you have well-regulated, high-power iron.

Well, Artie... what can I say? I'd really like to thank you for the explanation; it now all makes sense. I feel a lot better 'bout myself for making that mistake. Bad news is that I have to part with ca. € 75,00 ($ 115.00 USD) to get a solder station; that's the average price for that thing here in Italy.

Yours truly,

Pepe aka Lt. Kojak
Milano, Italy
 
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