NFV4 Piezo issues

[jerVic]

Hi. New member, first post. I recently purchased a blue 1997 (as far as I can determine from the serial number) Nitefly NFV4. Initially, the piezo pickup seemed to work properly, but now it's not. I get loud crackly static intermixed with proper guitar noise. It kind of has a "loose wire" sort of vibe to it.... I opened it up, and it looks pretty good, with the exception of the wire that runs between the piezo pickups and the little circuit board (see pic). So at this point, I'm suspecting that wire has a break or bad spot in it.... I'm not feeling comfortable with soldering in a new one, so I'd take it to a local tech to deal with that.

So my question for the group is, any thoughts on the issue? Does this seem like a reasonable diagnosis and treatment plan?

[mmmguitar]

Welcome, @jerVic. Did you plug the guitar in while the pickguard was off; to see if tweaking the wire you suspect of having the internal short caused any change in the noise being introduced to the signal? If indeed you're uncomfortable soldering, and you don't have a multi meter on hand to double check whether the hot and ground signal connections are isolated and/or bridging the components they should, then handing it off to a tech is likely for the best. Note that, in the worst case scenario that the issue is more than a broken wire, your old '90s NiteMix preamp may need to be replaced with the current version (specifically, the PRO-PCH-001 for pickguard-mounting), and will result in the manual mono/stereo switch on your '97's pickguard being replaced with an automatically switching version (meaning you can either plug the hole from the old switch, replace the pickguard, install something else there, or just live with the hole).

If you scroll down the page, there are Nitefly and NiteMix preamp diagrams which VJ has posted in this resource thread which your tech will surely appreciate.

[jerVic]

Thanks for your reply, @mmmguitar . I have done some more poking around, and have some more/new info. I've plugged the guitar into an amp, and have one string (low E) strung up.

- when I started, I was getting intermittent silence and distortion/buzzing when I plucked the string
- tapping on any of the 6 saddles produced a tapping noise through the amp.
- multimeter shows connectivity between all the saddles and the braid of the connecting wire where it's soldered to the circuit board
- manipulating the offending wire seemed to have no effect

but....

- spraying a bunch of contact cleaner into the piezo pickup volume seems to have mostly alleviated the issue. Now, if I pluck the string softly/moderately, I get normal guitar noises. If I pluck the string strongly/intensely, I get buzzing/distortion. The sound is now constant, not intermittent....

[mmmguitar]

Thanks for filling us in on a few more of the details @jerVic. Though I don't have a NiteMix preamp on hand to know the exact shaft length, the volume pot appears to be a dual gang A2KΩ PCB-mount. Unsoldering the pot from the board and jumpering the lug 2-3 connections to see if it effectively removes the pot from the circuit (for diagnosing whether the pot is alone in causing the issue) would be the next thing I try (I'm afraid I don't know if the preamp design expects to see a 2KΩ resistance load as a condition for outputting the signal to the jack).

[jerVic]

Thanks! I'll keep working on it, and report back. I'm encouraged by the fact that I've seen some improvements from just the contact cleaner. Makes me think the issue isn't as bad as I originally thought.

[jerVic]

So the contact cleaner seemed to be a temporary fix. The next day, it reverted back to its previous bad behaviour.

Going to find a local tech who is willing/able to have a look....

[mmmguitar]

So the contact cleaner seemed to be a temporary fix. The next day, it reverted back to its previous bad behaviour.

Going to find a local tech who is willing/able to have a look....

Darn. Please let us know how it goes.

[joeydorwart]

Im currently having the same issue w my piezo noise/ if anything enlightening comes from my guitar tech’s work ill post below

Cheers

[mmmguitar]

Im currently having the same issue w my piezo noise/ if anything enlightening comes from my guitar tech’s work ill post below

Cheers

Thanks for stopping in to let us know, and welcome to the site. Being as these guitars are changing hands all the time, the more hands-on knowledge gets shared, the better.