Broken phaser - faulty LFO?

[Dave]

I bought a 100% analog Ibanez phaser today, but it doesn't work properly.  When engaged, its definately doing some filtering, but its static.  What could be causing this?  A faulty (stuck?) LFO?  I may be able to return it, but I'd like to fix it if its possible.  Any help would be much appreciated.

Thanks,
Dave

[swt]

can you tell us what model is it? it's would be simpler to understand, and try to get a schem or a clue at least...

[RickL]

One possibility is that the wiper of the speed pot is not touching the substrate, either because of a cold solder joint or a faulty pot. I've had a couple of phasers with the exact symptoms you describe that were caused by this problem. Try cleaning the pot first then working from there.

[Dave]

can you tell us what model is it? it's would be simpler to understand, and try to get a schem or a clue at least...

It is an Ibanez PH-99, "Classic Phaser".  I haven't been able to find a schematic for it, but I'll continue looking.

One possibility is that the wiper of the speed pot is not touching the substrate, either because of a cold solder joint or a faulty pot. I've had a couple of phasers with the exact symptoms you describe that were caused by this problem. Try cleaning the pot first then working from there.

I am a true newbie to pedal construction, how do you go about cleaning the pot?  Its rather small (possibly sealed?), not like the ones I've seen before in instruments.

[swt]

i have one of those, it's a really great sounding pedal. it has a compressor expander ic (ne571), i think that bad solder is the place to start looking. there's no schem available that i know. it has lots of ics...so don't remember which one is the lfo. beguin resoldering the components from depth and speed pot and following the traces...'til you get to the ic.

[petemoore]

  I'd look at and try dating the electros...if not just replace...what year is that thing..?
  But see if I could find a Voltage swinging up/down/up as seen in LFO outputs...with the speed set low.
  Set up a little recorder so you can dictate the voltage readings/part #'s and Pin #'s, on the active components, then listen and copy them on paper.
  Don't overheat the IC's !!!