Problem with Pickups Ibanez 7420

[shoemaker27]

Hi everybody, Im new on this forum because I bought an Ibanez 7420 from a friend, I think my guitar has a problem, I cant find exactly what happen, but Im going to explain my problem so maybe other people has this issue...
I think the guitar has a problem because the output signal is not as loud as it must be, because I have an JS100 with ibanez pickups and the output signal is really louder that my rg7420, when I use distortion, it sounds like when you play with the volume knob in the middle, I test it with my GT-6 and both guitars, when I check the input level meter, with the RG7420 I only get 2 and with the JS100 I get almost 7 on the input, this is a big difference in the overall sound.
I think both guitars should have the same output because they have standard Ibanez pickups.
I checked the wiring, and compare to the Ibanez rg7420 schematics and looks Ok.
other issue is that using the 5 selector to the lower position(5) suppose to sound louder than in the 4 position. But sounds like a single coil in the 5 position. This is weird because in my other ibanez that I had the louder signal were in 1 position and in the 5 position.
If anybody has a 7420 I would appreciatte if ypu can post the levels of the output signals on every position.
I dont know if there is a bad connection, or damage pickups,.
Thanks all.

 

[Regor]

Did your friend buy it new? And if so, did he rewire anything?

I've noticed that my pickups have to be 'somewhat' close to the strings, but then again not 'that' close.

Here's a pic of the wiring schematic for RG7's. See if this helps you any.

 

[Hawksmoor]

I've had the same problem with one of my old 6ers and it was due to bad wiring. Have it checked by a tech.

 

[shoemaker27]

I asked my friend and he said that before he has a dimarzio on it, then he sold the dimarzio pickups and some thech guy installed the ibanez pickups and made the wiring again. I've checked the wiring schematics, and everything looks the same except that the volume knob doesnt have the 330pf capacitor. I have to buy it, but I think this is not the main problem, how I can know if the pickups are damaged?
Thanks,

 

[Drew]

Definitely not the main problem - that capacitor is the high pass filter that lets extra high end bleed through as you roll the volume down.

An aside - if you go to the parts section at www.carvin.com, they sell these capacitors, but the feeling I get is they're intended for the tone control. However, as I understand, a resistor is a resistor - wired in correctly, will this work as a high pass filter? I bought my UV rewired without one. Thanks,

-D

 

[jim777]

You could replace the pots cheaply, as good CTS pots run about 3 bucks a piece. If you are handy, replace the pots and see what happens. If you can, rewire from the schematic. Don't just put the wires on the new pots where they were on the old ones. Pots go bad; I just replaced all of them on my 175 and the guitar is much better sounding now.

 

[shoemaker27]

Im going to replace the pots, and I will post the results.
another question...
How can I know if the pickups are damaged or not working properly??
Any ideas??

Thanks!!!

 

[Digital Black]

Did your friend buy it new? And if so, did he rewire anything?

I've noticed that my pickups have to be 'somewhat' close to the strings, but then again not 'that' close.

Here's a pic of the wiring schematic for RG7's. See if this helps you any.

Notice in that pic, both pickups are labled "neck" . I't been like that for years on Ibanez.com
Your switch is definatly not wired right.. Ibanez mega 5 ways are very differnt from any other 5 way..

 

[Digital Black]

Also make sure the tabs on the back of the pots aren't touching any of the inside wood. The paint they use in th acontrol cavites is conductive..
Sometimes a loose nut on the pot causes it to twist , and the tabs end up rubbing the cavity wall..

 

[shoemaker27]

the schematic I use for compare my actual wiring is this:
http://www.deepsevenband.com/pics/w00rg7420.gif
My current wiring looks the same, but I dont know if this schematic is not the good one for my guitar, it appears RG7420, I will replace the pots to see whats happen...
I will post my results..
Thanks..

 

[dpm]

Hey, I can run you through how to trace the problem but it will have to wait 'coz I'm working right now.
Do you have a multimeter?

 

[shoemaker27]

yes I have one!!!
at this moment Im doing some test around..
I remove the wiring from the bridge humbucker to the 5 way switch and I connect the pickup direct to a guitar cable and then into my amp. The good news is the sound now is REALLY LOUD!!! so Im very happy because the guitar sounds great and the main problem should be maybe a bad connection, the 5 selector switch or the pots...Any ideas how to test the 5 way switch??
Thanks for all your post....

 

[dpm]

You can test the signal flow on the switch with the continuity setting on your meter.
Is that one of the switches with a green pcb?
There are actually a few different versions of that switch, the ones Ibanez use do not have the standard Strat layout, they actually work a bit differently.
The most common aftermarket version does have a Strat layout but looks exactly the same. If one of those is wired up to the Ibanez diagram it won't work properly.
It does sound like a bad connection/solder joint though.
Try running the pickup straight to the vol pot. If it still works fine then the problem is at the switch. If not it could be a pot, the socket or shoddy work.

 

[shoemaker27]

GOT IT!!@@@!!!!
It was difficult to discover, but the main problem was the black paint inside, then the pots was making a weird short circuit, I dont know but that kind of paint is conductive!!! when I remove the pots and plugged the guitar with the pots out of the hole the guitar sounds perfect...
Thanks all for the help!!!

 

[dpm]

Yeah, that's shielding paint. It stops noise getting into the signal.
Sounds like the pots were installed without their lockwashers so the lugs shorted to ground. That, or a pot had been twisted so it shorted on the side wall of the cavity.
Ah well, at least it wasn't anything drastic.