How To Measure Pickup DC Resistance

C_Becker

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Will a shorter output cable for the installed pickup method give a more accurate reading?
Compared to the 8 or more kOhm of the pickup, the resistance of the wire is very, very small. The wire is probably below 1 Ohm resistance, so you can ignore that.
 

oildrops

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I just installed new pots and pickups. The neck sounds full output, but the SD SH-5 in the bridge sounds like it's not getting the full output. I measure 13.5k for the SH-5 (duncan states Bridge: 14.1 k). Could there be a short somewhere, or does this seem normal? Could there be a grounding issue somewhere and still get the correct resistance reading?
 

MATTM

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I just installed new pots and pickups. The neck sounds full output, but the SD SH-5 in the bridge sounds like it's not getting the full output. I measure 13.5k for the SH-5 (duncan states Bridge: 14.1 k). Could there be a short somewhere, or does this seem normal? Could there be a grounding issue somewhere and still get the correct resistance reading?
Could be an issue with the switch, but if possible, post a pic of the electronics cavity so we can see if anything looks suspect.

Also, the difference from 13.5K to 14.1K could be the temperature at the time of metering. That doesn't raise any flags with me at all.
 

oildrops

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Could be an issue with the switch, but if possible, post a pic of the electronics cavity so we can see if anything looks suspect.

Also, the difference from 13.5K to 14.1K could be the temperature at the time of metering. That doesn't raise any flags with me at all.
I posted a pic in this thread http://www.mylespaul.com/forums/luthiers-corner/342998-installing-new-pots-could-use-some-advice.html, but posted in the luthier forum by accident. I just checked through all the wiring and tugged on every wire to check to cold joints. I unhooked the tone pot from the bridge pickup, which made no difference. I checked the lugs on the switch, and made sure they weren't touching. I re-soldered the pickup hot and ground, and the bent lugs on the pots. The only thing I can think of that I didn't check is where I grounded all the shielding together for the switch. I can't access it unless I de-solder everything because I didn't leave myself enough slack, so I was leaving that as a last resort.
 

freefrog

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I just installed new pots and pickups. The neck sounds full output, but the SD SH-5 in the bridge sounds like it's not getting the full output. I measure 13.5k for the SH-5 (duncan states Bridge: 14.1 k). Could there be a short somewhere, or does this seem normal? Could there be a grounding issue somewhere and still get the correct resistance reading?
14.1k in parallel with two 500k pots (volume and tone) is supposed to become 13.347k.

Here is a useful tool to check it if necessary: PARALLEL RESISTOR CALCULATOR

So, if the SH5 has a problem of output, it's apparently not a question of grounding. :hmm:
 

Wraptail

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It's totally normal: two pickups in parallel measure the sum of their DCR's divided by 4. And you have 4 pots in the circuit instead of two, whose DCR drags down the whole DCR too.
Great point that isn't mentioned often.
 

peanutavalon

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Here's another way too, assuming the pickup is already wired up:





One leg of the meter gets clipped to the volume pot lug where the pickup is connect, the other leg clipped to the outer braid of the pickup. Make sure your volume is all the way up :)
I just did my cc les paul bridge only using the already wired method..it read 7.77.

Then I did my benchmark ro using the same method...it read 4.04. I realize the benchmark runs have the lower output E buckers but that is a substantial difference to me. The funny thing is the E buckers are just as loud and more articulate.....Any input on this one guys? thanks

edit...never mind..someone suggested putting my cable in the guitar input...solved the problem and the pickups read 7.34.
 

Yulian

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Hi!
I am new to this forum and that's my first post, so please bear with me ))
I've recently bought a 2017 Tribute Gibson Les Paul second hand. I love the way it feels and sounds. However It seemed strange that the bridge pickup sounded like twice as lower volume than the neck pickup. I tried to check the resistance through the cable this way


And was confused with the results. This model is supposed to have 8 kOhm 490 pickups, yet the neck reads 4.64 and the bridge 5.9, with the middle position around 2.9.

On my strat this method gave results very close to specified resistance values.

Is it normal, or there may be some problem with the pickups or wiring?

As a matter of fact I could not open the control cavity cause the screws do not give way, I feel that putting extra-pressure would strip them. so any advice in this respect will also be appreciated.

Thank you!
 




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