Noise Shielding H-137

[Cryoman]

I don't know if other H-137 owners have had noise problems (fairly inherent to single coil P-90 pickups.).  My H-137 was noisier than I wanted and found that a large area for noise "pickup" was in the switch cavity.  Before my shielding, rubbing the switch cavity back cover plate while amplified brought out major pops, scratch and hisses. (Much like the pickguard plate on Strats...).  This was my major clue as to the largest culprit.

 

So I used standard issue alumunum AC duct tape to completely shield the cavity starting with an oval piece at the bottom. I later cut out exactly, with an Exacto knife, the hole for the switch through the guitar's top. I then used mulitple pieces of tape with one corner bent under itself for electrical conductivity to the next piece (Note: Al duct tape does NOT necessarily have conductive adhesive, hence the reason to do this...). When you reinstall the switch, its housing/body has connectivity to the foil shield which completes the grounding of all the aluminum foil to the switch ground wire.

 

Lastly, I covered the inside of cover plate with the same aluminum tape.  Trim it all up so that you don't see any alumunium when you re-assemble the cover plate.

 

Wahlah... nice little Faraday cage.  Noise of this guitar is WAY, WAY down. No pops or hisses ever. Only the tiny bit of P90 hum left when cranked.

Took about 25 minutes to complete.  I highly recommend it...

 

Cheers,  Cryoman

 

http://i221.photobucket.com/albums/dd302/cryoman_bucket/H137shielding002.jpg[/img]

 

 

Full size here: http://i221.photobucket.com/albums/dd302/c...hielding002.jpg

[brentrocks]

that is great man!  i should do that to my 137...although the noise on mine isnt really that bad

[Dick Seacup]

Interesting idea; thanks for sharing it!  My Hamer P90 Special is noisy as all get out, especially downstairs under the fluorescent lights.  I might have to give this a try.

[GuitArtMan]

Tip:  If you have a local stained glass suply store, they sell one foot square sheets of adhesive backed copper foil for not much coin.  I prefer this to the aluminum foil tape as it's usually easier to work with.  If you have a good electronics shop locally (Fry's electronics will do) you can buy a conductive paint for shielding inside the guiars cavities. 

[Cryoman]

GuitArtMan,

 

Thanks!!  But please check that the backing adhesive on the copper foil is conductive.  Many are not and these then have no advantage over the aluminum, you still have to bend a corner over to have metal on metal.

 

Cheers,  Cryoman

[GuitArtMan]

GuitArtMan,

 

Thanks!!  But please check that the backing adhesive on the copper foil is conductive.  Many are not and these then have no advantage over the aluminum, you still have to bend a corner over to have metal on metal.

 

Cheers,  Cryoman

Yeah, that's why I prefer the paint.  I tend to use the foil only on flat surfaces like the back of pickguards, control plates, etc.

PS  Good job btw - I haven't bothered to shield my 137 yet.

[cosmikdebriis]

From a shielding point of view, it's not strictly necessary to cover every last inch of the cavity so you don't need to be too precise. Just make sure your shielding is earthed else it won't do anything. Copper tape is a better conductor though, to be honest, I doubt it'd make much difference.

[SouthpawGuy]

Hi guys .. are these H-137s equipped with Lollar P-90s ?

I was under the impression that those pickups were noiseless, or is that just marketing ? ( or just me being misinformed  :- )

I'm kinda leaning towards a P-90 equipped guitar myself and I tend to play plugged in right in front of my pc monitor.

I use a Line 6 Toneport UX2 with Gearbox and Guitar Rig and standard single coils are unuseable with high gain or distortion even with noise gates / suppressors etc.

Also in regard to the P-90s height adjustment -- is there any ? Will the pickups balance for loudness ?

Sorry for the slightly off topic quiz.

Any feedback ( pardon the pun) would be very helpful.

Thanks

[Cryoman]

The H-137's indeed have the Lollars.  They are really a fine pickup.  I'm pretty certain a P-90 is a P-90 is a P-90.  If Jason Lollar were shielding them internally or making them "noiseless" it really would no longer be a P-90 anymore.  On the H-137 there is no pickup height adjustment although you can adjust the individual pole pieces.  The volume balance, for me, is perfect. Maybe just by happenstance... I've not adjusted even the pole pieces (which I should to better match the fretboard radius...)  This is truly a set and forget guitar for me. One of the reasons it's a favorite of all the guitars I own.

 

Cheers, Cryoman

[GuitArtMan]

The H-137's indeed have the Lollars.  They are really a fine pickup.  I'm pretty certain a P-90 is a P-90 is a P-90.  If Jason Lollar were shielding them internally or making them "noiseless" it really would no longer be a P-90 anymore.  On the H-137 there is no pickup height adjustment although you can adjust the individual pole pieces.  The volume balance, for me, is perfect. Maybe just by happenstance... I've not adjusted even the pole pieces (which I should to better match the fretboard radius...)  This is truly a set and forget guitar for me. One of the reasons it's a favorite of all the guitars I own.

 

Cheers, Cryoman

Yes!  The volume balance is perfect.  All positions are the same volume when the volume controls are full up.

[High Flying Bird]

That was smart thinking on your part.  Me and 3 other guys I play with worked at the same local electronics company.  We were R&D techs.  I worked in the power supply lab for several years and got to built the prototypes of the home made power supplies that the engineers designed.  I even took the pre-production units to have them pass the EMI testing. 

 

When doing a new design I would always make a bed with a thin copper sheet taped to the surface of the breadboard for the Pulse Width Modulator chip.  Bob was close to retirement and knew all of the tricks, taught me how to ground and shield areas to reduce noise.  Since I was gifted with my hands I would miniaturize the circuits and challenge him to think.  We worked out good together but I never really learned the craft of the electronics like he did. 

 

To get maximum effect on your shielded area you might want to solder a wire between the tape and the ground on the switch and in the volume/tone cavity.  This is where copper may be an improvement over aluminum.  I wouldn't worry with the covers but in an EMI test it would help, but that is negligible.  Keep in mind that I don't have the slightest idea of how guitar circuitry works so I may be blowing smoke out me....

 

For my 535s I might just get some of that paint and blow it into the f-holes.  "Jethro, I wouldn't do that boy" 

 

Cryoman, voted best H-137 pickguard designer.  Cryoman is one thinking muthu....., muthu.......!

[Cryoman]

High Flying Bird,

 

Thanks man!  I'm satisfied (tested with Ohm meter) that the switch body grounds to the foil and hence no need for that extra soldered ground wire (although typically your good suggestion is needed say for a Tele front pickup...). 

 

Cheers, Cryoman

 

 

PS. I STILL have materials left for two or three of my H-137 pickguards (in B/W/B/W/B).  Free for the asking to any HOC member with an H-137...

[dblazer]

Tip:  If you have a local stained glass suply store, they sell one foot square sheets of adhesive backed copper foil for not much coin.  I prefer this to the aluminum foil tape as it's usually easier to work with.  If you have a good electronics shop locally (Fry's electronics will do) you can buy a conductive paint for shielding inside the guiars cavities. 

 

I used the paint (got it from Stew-Mac) for my Telecaster, it worked really well.

 

This looks like a GREAT "how to" thread, thanks. I've now got to check out mine more closely, I haven't had the "big" amp turned up with it yet, I've been playing through the Pandora a lot.

 

Thanks Cryoman, and you too GuitArtMan.

[GuitArtMan]

I used the paint (got it from Stew-Mac) for my Telecaster, it worked really well.

 

This looks like a GREAT "how to" thread, thanks. I've now got to check out mine more closely, I haven't had the "big" amp turned up with it yet, I've been playing through the Pandora a lot.

 

Thanks Cryoman, and you too GuitArtMan.

I love StewMac and do like to support them, but at the same time they resell stuff that you can find elsewhere for alot less $.  The conductive paint is one example.  Next time try an electronics supply store - you can save yourself a few bucks.

Bob

[dblazer]

I love StewMac and do like to support them, but at the same time they resell stuff that you can find elsewhere for alot less $.  The conductive paint is one example.  Next time try an electronics supply store - you can save yourself a few bucks.

Bob

 

Thanks Bob, I'll check it out for sure.