Thread: Wiring posts allowed??

Originally Posted by old_picker

....he had his hands on a mike that was live [240 volts] and the other on his bridge - yes - bang - 240 volts followed the path of least resistance...

I haven't done anything with mic's so I'm not real sure about them apart from the theory of operation, but how could a mic become live to 240V?

Back to the post... Try the SD website, there's plenty of schematics there that might help
http://www.seymourduncan.com/support/schematics.shtml

Originally Posted by Malibu

Ihow could a mic become live to 240V?

Really green Roadie plugged it into a wall socket

http://www.guitarnuts.com/index.php

Great info on wiring and sheilding, reducing hum etc.

A good site Paul, one I'd forgotten about..
I had a long read on the shock hazard with mic's etc and what they say makes sense in that it all boils down to faulty equipment/wiring/supply. There's so many 'earths' in home audio and stage PA's that it's pretty easy to have one become loose through a connection or faulty solder joint.
Unfortunately all you stage muso's can't control the outlet where you plug in, you've got to trust the electrician (or the otherwise dodgy bloke) that put the outlets in.
There's a lively discussion here on the pro's and con's of DIY home wiring, with the rules and regulations discussed, which runs through a similar vein. Check it out if you're interested...
http://www.woodworkforums.ubeaut.com...ad.php?t=41628

Hi

Your Tele does have an earthed bridge, unless you've cut the wire. If you look at the brass plate on the bridge pickup you'll see the wire goes from the coil to the baseplate. The pickup mounting screws go through the bridge and the brass plate, so there's your earth.

Is one of your P90's reverse wound / reverse polarity? If so it should be hum free in the middle position. Just the neck and bridge pickup on their own will have a smidge of hum but once you start playing that'll drown out any hum.

Neither tele has an earthed bridge. I built both and didnt put a earth strap from the bridge on either. Both of them were very quite

The p9o's do sound quieter with both p/ups on. Currently I am redoing the hot lines with shielded [braid] wire and using more of a star grounding with the earths. IE all earths running to a commom point in the cavity and then to the jack.

Updated wiring pic


Any further comments gratedully received.

Your Tele doesn't need a separate earth strap, it's built in, unless you've cut the wire link.

I recently built a Tele style tenor guitar for someone in Canada... customs decided to undo the bridge screws so he had to reassemble it with some help from me. To cut a long story short he kept on about the hum and popping noises, so emails went back and forth checking that the black wire on the Tele bridge pickup having the little solder link to the brass plate, the earths all being good, all the normal stuff. He mentioned at one point that when he put his hand on his mike the humming from the guitar stopped. I suggested he check the earths on his powerpoints... his electrician came to look and is coming back to rewire the house... none of the power outlets in his house have earths of any kind!

Back to your diagram.... are the tone pots working? I usually run the caps from the centre lug of the tone pot to earth, with the outside lug of the tone pot wired to the opposite outside lug of the volume pot. I have to confess to never having wired anything with one volume and 2 tone pots except Strats, for which I use Fender's Jimmy Vaughn setup. I've attached that diagram and anothe one for wiring two P90's. I know they're not exactly what you want but hopefully they'll be of some help.

I guess that says it all about earthing a bridge.

I have just finished rewiring the p90 project and will check it out for hums tomorrow.

I sheilded the pickup cavities, ran coax on all the hot leads and grounded everything to a central point in the control cavity. Then it goes to the earth of the output jack.

That's the way I did the teles and it worked fine with no bridge to earth wire.

Will post back with the results and hopefully some pics.

Hi again

While you were posting I'd edited my post... sorry.

Re the Tele earth, I've attached a pic that shows that little link wire on Tele bridge pickups. It's actually a great idea provided you also have a fairly standard neck pickup.

Anyway... fingers crossed your wiring's fixed and hum free. Everyone should have at least one guitar with P90's.

Originally Posted by JupiterCreek

none of the power outlets in his house have earths of any kind!

reminds me when I was sent to Hanoi in the 90's to troubleshoot a $250000 computer video editing installation in the local tv station purchased by an english NGO to make an HIV-awareness soap opera.

Nothing worked properly. Then when I was 'round the back of the machines my bum happened to touch the wall while I was plugging in video leads. Got a spark :eek: Then I tested the chassis of the vidotape deck ($85,000 digital betacam) and found it 240v live. No earths anywhere! When I asked why not I was told simply that it costs 30% more to wire earths and no-one in vietnam can afford it.

nonetheless, when I had the electrician run a wire from the power board to a piece of rusty reo outside in the garden, everything worked ...

Well I done all the extra work on the hawk junior's wiring and it never made a scrap of difference. So I strung a piece of wire from the bridge and hooked it round the jack chassis and it shutup.

So now I gotta cut a hole from under the bridge to the control cavity BBRRR!!!

here she is and you can see what I am up against with getting that hole through.
You can see the earth hanging off the schaller roller bridge.

Originally Posted by old_picker

Well I done all the extra work on the hawk junior's wiring and it never made a scrap of difference.

... and very very rarely will...

Originally Posted by old_picker

So I strung a piece of wire from the bridge and hooked it round the jack chassis and it shutup.

... sometimes its best to not second guess years of guitar manufacturing. Bridge grounds are there for a reason... they work!

Originally Posted by old_picker

So now I gotta cut a hole from under the bridge to the control cavity BBRRR!!!

here she is and you can see what I am up against with getting that hole through.

Buy a long drill bit. Simple!

Guitar looks good, lets see more of it.

I bought a set of "aircraft" drills on eBay.... they range from 1/16" to 1/4", they're 12" long, and the whole set was about US$20 or so.... absolute bargain!

But in your case I'de be drilling from under the bridge to the back pickup cavity. I just drill the hole anywhere under the bridge, then use a Dremel to cut a groove from there to one of the screw holes. Bare 1/2" of the wire, poke it in the screw hole, then tuck the wire into the groove. The wire doesn't need to be anything special. Light hookup wire is plenty heavy enough.

I have a 1/4 x 12" bit which I did exactly as you said.
It's always scary for me cutting a hole like that. I used a piece of sticky copper foil under the bridge screws and the lighting wire I used had plenty strands so I just fanned it out over the foil and one of the screw holes. Tightened it down and checked the bridge to the jack chassis with the multimeter for resistance. I got a 0.