How to "Read" pickup winding values while Pups still in guitar, and MORE!!!

[animalfarm]

I just posted this in another thread, it HAS come up before,

soooo.......

 

"I have no way of testing the output"......

 

SURE you do! Have a cheap digital multi-meter?

 

1. Plug a short guitar cord into the input jack of the guitar.

2. Turn both volume knobs all the way up, both tone knobs down.

3. Set multi-meter to read higher than 14K (probably has 20K setting?).

4. Click toggle switch to "Rhythm", place one meter lead on round "barrel"

of OTHER end of guitar cord, place second lead on pointy "tip" of cord. (There will

be a plastic insulating spacer seperating the two).

5. Read meter - this is the Kilo-Ohm " winding of your neck pickup (maybe around 8K?).

6. Click toggle switch to "treble", repeat above process.

7. This reading is the Kilo-Ohm winding of your Bridge pickup (maybe around 13K?).

 

If they're the same, you'll see it. If different, you'll see that, too.

 

[TWANG]

yep 13K.

that's the way to do it.

you can test pots that way, too..out of the guitar.. I've found more than one with dead spots, etc.

 

and flip your three way. shows you what the middle position ohms are...

and test your speakers the same way.. one probe to hot, one to ground .. ohms setting.

 

a dmm will have a capacitor setting, too

 

and try to keep your fingers off the probes tips or anything you're trying to read.. messes up the reading sometimes.

TWANG

[AnthemBassMan]

-Very useful tip you put here. I've done this quite a bit but never thought of listing it as a how to. A lot of people will use this one.

 

L8R,

Matt

[Gordy01]

Like Twang said, you can test your pots like this too.

Put one lead on the input post, and one on the output post.

Turn the pot up full and you get the max reading.

Turn it down and you get the minimum.

[animalfarm]

Twang and Gord are correct fer sure about the pots. I usually

replace the pots on any rebuild I do, and I also have a habit

(bad?) of saving some of the previous pots for "Emergencies" -

both mini and full size.

 

Testing the pots with a multi-meter actually

helped me find a problem INSIDE a new pot that had an accidental

drop of solder hit the outside between tabs while wiring up. The solder

blob bridged two posts, so I used the solder sucker to remove the excess

between the posts. Looked good, but STILL shorted out! Knob position

made no difference, so I took the option of removing the pot from the

circuit and physically disassembling it/unbend the tabs on underside

and remove cover....

 

Guess what? Inside the cover in the area between

the two tabs was a whisper-thin line of solder that had splashed under

the cover and attached to the inside. Didn't look like much, but was

enough to ground out signal. I scraped solder off, reassembled, and

had a WORKING pot again. Solder can do some freaky things even if

you are careful and tin and wipe the iron tip constantly...

 

PS - When soldering pots, be sure to turn them completely OFF!

[Fadedepi]

AF,

 

If the PUP's your checking in this thread are Epi's, would you please tell me which models they are? I'd like to compare them against the Epiphone Pickup chart I have. It might give us some interesting output numbers, if there's some big differences. Or even if they're right on the money.

 

Faded...

[animalfarm]

AF' date='

 

If the PUP's your checking in this thread are Epi's, would you please tell me which models they are? I'd like to compare them against the Epiphone Pickup chart I have. It might give us some interesting output numbers, if there's some big differences. Or even if they're right on the money.

 

Faded...

[/quote']

 

I'll throw 4 EPIs and 2 Gibson readings at you. May not help totally because

the first 3 sets were taken after the gits had been in a room with a regular

temperature of 80+ degrees. The second 3 sets were just taken 30 minutes

ago, it's been 48 degrees, and the room the gits were in averaged 60- 65 degrees,

even though the gits were in cases...

The TEMPERATURE OF THE PICKUP will affect the Resistance output +/- 500 ohms easily.

IE: Take your readings, play your git for 30 mins, take readings again...will be different!

 

1. EPI HOTCH (G) - 13.3K

G-400 bridge/LP Std bridge

EPI 57CH (G) - 8.13K

G-400 neck/DOT neck/LP Std neck

 

2. EPI HOTHB8B - 13.14k

LP Studio/LP Classic bridge

EPI HB6N - 8.12K

LP Studio/LP Classic neck

 

3. EPI HOTHB8B - 13.58K

LP Studio/LP Classic bridge

EPI HB6N - 8.30K

LP Studio/LP Classic neck

 

Pickups at COLDER Temp:

 

4. EPI HOTCH (G) - 12.72K

G-400 /LP Standard bridge

EPI 57CH (G) - 7.70K

 

5. GIBSON 498T - 12.72K

Bridge pickup, set 1

GIBSON 490R - 7.46K

Neck pickup, set 1

 

6. GIBSON 498T - 12.32K

Bridge pickup, set 2

GIBSON 490R - 7.19K

Neck pickup, set 2

 

Kind of ODD on paper, as I KNOW the GIBSON pups are hotter!!!

[animalfarm]

Afterthought - I've posted this 2 or 3 times, but was probably

lost when the website crashed and dumped months worth of

posts. Applies to pickups, too. May be useful...

 

 

 

Capacitor effect on Tone/bandpass:

 

[freak show]

Instead of posting it in the "Feedback" section where I'm sure no one is "listening", I thought I'd make a suggestion here.

 

Some of you guys know a "heck" of a lot about guitars and do some extremely ambitious projects. The only problem is that the this information ends up buried under piles of "Is my guitar a fake?" and "HNGD" threads.

 

Wouldn't it be sensible to have a section "Epiphone Tech" (or something like that) where mods, projects and other technical matters are discussed?

 

It seems to me that it would make finding the old threads easier, if they were grouped together...

 

B)

[Ricochet]

This thread may be usefull to you...

 

"Gibson and Epiphone pickups DC-resistance values"

 

http://epi.p3net.net/bbs/viewtopic.php?f=4&t=1814

 

Copy/paste at will... LOL!

[deflepfan]

Instead of posting it in the "Feedback" section where I'm sure no one is "listening"' date=' I thought I'd make a suggestion here.

 

Some of you guys know a "heck" of a lot about guitars and do some extremely ambitious projects. The only problem is that the this information ends up buried under piles of "Is my guitar a fake?" and "HNGD" threads.

 

Wouldn't it be sensible to have a section "Epiphone Tech" (or something like that) where mods, projects and other technical matters are discussed?

 

It seems to me that it would make finding the old threads easier, if they were grouped together...

 

B)

 

[/quote']

Hear! Hear!

[wedgeSG]

+11 this really should be its own seperate heading like "Epiphone Tech" or something similar. Guitar aimed, like the Amp section is. Heck of an idea~!!

BTW - is the soldering on a pot that's not completely closed down a given that the pot will be shot? Oddly enough I've never heard that it was mandatory,

I can see where it's a good idea, but if you just forgot, is the pot definately toast? Kinda got a mysterious problem at the moment and maybe this was the reason.

Wound up dropping a pair of 498T's in (since the EBAY sourced 490R was actually a 498T), and measured as per above mentioned method showed very similar output.

In the guitar with a pair of matched .022 Orange Drops the output on the neck was about half was had been read by the meter. Realizing something was wrong we

installed a new matched pair of .022 ceramics and the whole thing died. Got zero output from anything now. Haven't had a chance to re-visit the guitar as yet to further

chase down the problem; but maybe we did in fact have a pot open, I dunno. I do know I've never run into so much hassle on a simple pickup swap though it's been PITA.

 

Wedgie

[RSDx]

Thanks, animalfarm ..... dragged out my cheap meter for kicks, I got 13.71K on my bridge and 8.39K on my neck .... '07 LP Std +top w/ stock 'buckers, @ room temp with a short guitar cord, vol pots maxxed, tone pots zeroed.

I feel I learned something useful with this thread, and yeah, I think there should be a "tech" section here, in some shape or form.

[bluelake07]

Epiphone P90(Casino) (Alnico5) 8.1KO

 

Hmmm, I measured 11.58K neck and 12.17K bridge on my 2003 MIK Casino.

[animalfarm]

This thread may be usefull to you...

 

"Gibson and Epiphone pickups DC-resistance values"

 

http://epi.p3net.net/bbs/viewtopic.php?f=4&t=1814

 

Copy/paste at will... LOL!

 

Followed your link, excellent work! It's been printed and is now in my collection

of 3 ring binders of "Guitar Info". I feel that knowing the DC resistance value of

a pup allows the end-user to:

 

1. Make an informed decision regarding the expected Tonal output of a pup regarding

placement on a git. IE: A lower value pups will produce "softer, less harsh" tone than

a higher value pup. Hence an EPI DOT will use the lower value 57CH (G) pup in both

positions rather than tossing in a higher value Alnico PLUS for the bridge position. Of

course, a DOT is NOT a solid-body (duh). And yes, the type of magnet used will also

influence the tonal output - metal vs. ceramic.

 

2. If expected readings are horribly off, the end-user can now see "sumpin' ain't right".

I have a bridge pup that read 13.4K. My sister's little girl somehow latched onto it, then

dropped it on floor. It now reads ZEEEERO!!! Great, internal wire break. I'll go ahead and

cut the solder joints, remove cover and look, just for grins. Probably hopeless...

 

 

WEDGE: About the only way to literally fry a pot is too much heat for too long on the

connection you're trying to solder - a low wattage iron can be the guilty party.

 

What schematic are you using for wiring direction? Just wanting to make sure you're

soldering onto the correct tab on the tone pots.

When you did the neck pup measurement, tone OFF, toggle switch in Rhythm, NOT

accidentally in middle? Regarding the fact that you now have ZERO output from any pup

in the guitar, immediate thought is that you've accidentally unsoldered a ground wire or

even broken it internally if you were moving the wires around a lot. Interrupt the circuit,

whole thing goes.

[animalfarm]

Epiphone P90(Casino) (Alnico5) 8.1KO

 

Hmmm' date=' I measured 11.58K neck and 12.17K bridge on my 2003 MIK Casino.[/quote']

 

Vewy, vewy interesting.... If you used a LONG git cord for this, the added wire in

the cord will introduce additional resistance. Still, if short cord used, and pups are

actual p-90s, perhaps overwound? Tone knobs OFF?

[animalfarm]

Thanks' date=' animalfarm ..... dragged out my cheap meter for kicks, I got 13.71K on my bridge and 8.39K on my neck .... '07 LP Std +top w/ stock 'buckers, @ room temp with a short guitar cord, vol pots maxxed, tone pots zeroed.

I feel I learned something useful with this thread, and yeah, I think there should be a "tech" section here, in some shape or form.[/quote']

 

Sounds like Alnico Classic PLUS in Bridge,

Alnico Classic in Neck.

[animalfarm]

Digging for one of my old posts, saw this, kicked it up

for possible info to newer folks.

 

BUMP....

[Bender 4 Life]

Heavens YES !!!

a sub forum titled "Epi./General guitar tech" is a much needed upgrade to this forum.

Perhaps we need to let the "powers that be" know this through the "Feedback" forum?

I'll go 1st.............

[Ricochet]

Epiphone P90(Casino) (Alnico5) 8.1KO

 

Hmmm' date=' I measured 11.58K neck and 12.17K bridge on my 2003 MIK Casino.[/quote']

 

8.1K is the official reading copied from an old Epi brochure. And much closer to a classic P90 output.

 

My Kat's P90s are between 11-12Ks too. My guess is that Epi somewhere along the line moved to a different gauge of wire but just kept the same amount of winds...

[tflanster]

Vewy' date=' vewy interesting.... If you used a LONG git cord for this, the added wire in

the cord will introduce additional resistance. Still, if short cord used, and pups are

actual p-90s, perhaps overwound? Tone knobs OFF?[/quote']

 

You can measure the resistance of the cord before attaching it to the guitar, then adjust the resultant values. Just short out the cord at one end by attaching a piece of wire between the barrel and the tip and measure at the other end. There probably isn't a big difference.

[SamBooka]

You can measure the resistance of the cord before attaching it to the guitar' date=' then adjust the resultant values. Just short out the cord at one end by attaching a piece of wire between the barrel and the tip and measure at the other end. There probably isn't a big difference. [/color']

 

Understand tho that what makes a big part of the effect the cord length has on tone isnt the resistance as much as it is the capacitance. All guitar cables are tone controls. The longer the cable the greater the range of frequencies that get grounded out.

[tflanster]

Understand tho that what makes a big part of the effect the cord length has on tone isnt the resistance as much as it is the capacitance. All guitar cables are tone controls. The longer the cable the greater the range of frequencies that get grounded out.

 

Well' date=' sure. Perhaps I should have said a person could measure the [i']values[/i] of the cable rather than just the resistance. My only point was that if a person doesn't have a short cable - or even if he does, measuring the resistance and reluctance - the capacitive effect, can help if that person wants truly accurate information.

 

I maintain though that an ohm or two really doesn't matter if we're just checking to see the differences between P/U's. A reading of 130.8 ohms compared to say, 129.6 ohms still gives the basic info. There are +/- tolerances in every electronic device, including the meter, so 130.8 +/- 5% is pretty much as good as you get. Same goes for cables - monsters vs common everyday cheapos, for example. Heck, I've made audio cables from TV RG antenna wire when I need something fast, and which work just fine. I use one on my tuner.

[fenrirlupus]

This only applies to 50-year-old designs.

For example: the lace alumatone's (sp?) output cannot be measured by resistance.

[animalfarm]

This thread originally posted in Oct 2009.

I rcvd a PM requesting pup values, and included this thread

as a link in my response.

 

Gave me a chuckle to read again, as it was in the "Pre-DIY Sticky"

days...

 

BUMP for newer members!