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How to tell if a P.U. is D.O.A.

9/13/2000 6:30 PM
Adrian How to tell if a P.U. is D.O.A.
Hi ya'll!  
I have a guitar that may have a bad P.U.. I am hoping the crew here can help me determine the FACTS!  
- Guitar is a 70's Epi Coronet(?) with two metal covered humbuckers.  
- For a while I was using this Guit. as a test instrument for homebrew effects and they all sounded like they had a nasty scrapey distortion on hard hit chords.  
- when lowering the front HB it failed - no more output - bridge PU is fine and bridge only switch position is fine.  
- the switch checks out for continuity as do all the grounds i can find.  
I can find no wiring fault using my level of sophistication in trouble shooting (i have never really worked on guitars, just EFX, and a little amp work)  
Before I go and buy a new PU what should I check?  
I am a big cheepie and would positively HATE to buy a PU and then find a different problem.  
Pointers extremely welcome!  
- A
9/13/2000 6:35 PM

Disconnect the pickup leads and check for continuity across the pickup itself. Should be between 5 and 15 k ohms. If you get open or short circuit the pickup has a problem.  
Pretty much all pickups are repairable - but it can be more trouble than it's worth.  
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9/13/2000 7:59 PM
Adrian How to tell if a P.U. is D.O.A. !
Thanks Liam - I'll do as suggested. If it is open or shorted I may try a repair even though I'm happy to buy a new PU if needed. I like getting into things - if it is broken I have nothing to lose and much to gain in the way of knowledge!  
For example I fixed a non-functional key on an olde synth i have - it sure makes for a better keyboard.  
Thanks again,  
- A
9/13/2000 8:33 PM
Glen H.
Your Epi is likely a Crestwood model...  
Glen H.
9/13/2000 10:42 PM
Double Cutaway, Black, Les Paul-type headstock. white/clear pickguard. several pieces of wood comprise the neck, white dot inlays, Les Paul-type bridge.  
2vol 2tone knobs plus the selector down near them so you can accidentally hit it.  
Is that the Crestwood?  
- A  
Thanks Glen.
9/14/2000 5:22 PM
Glen H.

That sounds like the one (just can not recall the headstock shape). Body thinner that usual. Cutaways  
different from a LP jr. & Melody Maker. "C" with line through middle on either pickguard or truss rod cover. Two semi-cheezy humbuckers (no offence meant here, the PU's are just not up there with the standard Gibson 49X's...)  
The Crestwood had a few permutaions over the years, from fixed bridges to whammy bar setups. Also, some had chrome hardware, others had gold. Finishes varied from sunburst to solids. Some had set-necks, others were bolt-ons.  
The guitar player for Hole used to use one a few years back. I really like the design, very cool!  
Glen H.
9/18/2000 8:50 PM
Thanks Again for the Info.  
I did manage to fix it and learned something good in the process.  
this: the "continuity" setting on a DMM may read good even when a connection is not good enough at low signal.  
- Duh - Use resistance! or at least in combo.  
The "hot line from the PU was dead at the pickup end due to a bad joint to begin with and the pressure of trying to lower the pickup against this block which the neck bolts on to. the cavity is too shallow as a result of the thin body. the front PU can't go even fairly low.  
I guess it is a budget guitar for a reason! Still much better that the real cheap guitars of the 70's!  
Hondo , anyone?
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