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Hoffman Amps Forum image Author Topic: High Resistance Reading P90 pickups  (Read 5830 times)

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Offline dynosoar1

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High Resistance Reading P90 pickups
« on: January 02, 2010, 11:43:26 am »
I'm getting a reading of 20K and 18k respectively on my P90s.  Guitar is 1961 Gibby.  I'm measuring them from the guitar cable and not the leads directly, but I checked every other guitar i have and the method works fine.  Does this indicate broken pickups??

Offline tubesornothing

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Re: High Resistance Reading P90 pickups
« Reply #1 on: January 02, 2010, 12:35:43 pm »
Somethings odd.  I measured my 56 goldtop the way you described and I see 9k and 8k.  4.5k with both on.

Offline stingray_65

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Re: High Resistance Reading P90 pickups
« Reply #2 on: January 02, 2010, 01:35:55 pm »
Have you checked to see your volume setting?

how is the sound otherwise?

do you have a treble bleed cap? and does it have a shunt resistor?

what is the switch position? and does it run your pickups in series?

Just a few things off the top of my head that could give you an odd reading on an otherwise normal pickup.

however if it sounds different than you remember, you may have issues
My mind is aglow with whirling, transient nodes of thought careening through a cosmic vapor of invention (H. Lamarr)

Offline dynosoar1

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Re: High Resistance Reading P90 pickups
« Reply #3 on: January 02, 2010, 03:54:19 pm »
When volume pot is dropped to 1 or 0 it reads about 22 ohms.......reading is 75 kohms at half volume (5) and about 20k ohms at full volume (10).  Could it be a bad pot??  The pickup is functional and sounds ok, but I'm wondering if it would sound different if the possible issue was resolved?  I have only known what the pickup sounds like as it is now as its a recent acquisition.

Offline jjasilli

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Re: High Resistance Reading P90 pickups
« Reply #4 on: January 07, 2010, 07:16:09 am »
Somethings odd.  I measured my 56 goldtop the way you described and I see 9k and 8k.  4.5k with both on.

Ditto for my '69 Goldtop (7.8K 8K & 4K) with controls dimed.  Readings drop to near zero with controkls at 0.

Offline Geo

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Re: High Resistance Reading P90 pickups
« Reply #5 on: January 07, 2010, 03:34:25 pm »
When volume pot is dropped to 1 or 0 it reads about 22 ohms.......reading is 75 kohms at half volume (5) and about 20k ohms at full volume (10).  Could it be a bad pot??  The pickup is functional and sounds ok, but I'm wondering if it would sound different if the possible issue was resolved?  I have only known what the pickup sounds like as it is now as its a recent acquisition.

Could be a bad pot. Note how at half volume you get 75k ohms. At full volume you should get ~8k ohms, the coil's DCR. 20k is somewhere in between these. It looks like your pot is not quite rotating all the way. It may be stuck at say 80%.

If the guitar sounds fine, don't worry about it. ;)
When I was a kid we played cowpersons and native americans.......

 


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