Rangemaster noise!!!

[pupina]

Hi everybody, I can't understand what's happening to my Rangemaster...I built it almost one year ago and didn't use it for a while...recently I picked it up and insert in my chain...wow, this thing is very noisy even when is bypassed!!! I use true bypass in it and I notice a continuous rustle in bypass mode (don't know how to explain in English) like radio interferences without voice.....the rustle finishes only removing the battery.
Obviously when activated, the booster push the level of the noise over the top!
For this pedal i used an OC 44 bought from Smallbear, 1 meg resistor for pop noise free operation, metal film resistors, poly caps and 2 25 uF electrolytic, true bypass (3PDT) and trimmers for biasing the tranny at 7 v. Measurements are perfects....this damn rustle, hiss noise comes from the circuits, i dunno from which part.
Does someone can help me fixing this thing? Everyone has experienced the same problem? Any advice will be appreciated, thanx in advance

Pupina

[Zben3129]

Pupina,

If you are using true bypass and there is still noise when you are bypassed, then that means you either have a bad/loose wire somewhere, or you are picking up rf.

I have a few questions,

Are you using a metal box
Are you using shielded wire
Are you using metal jacks or plastic

Zach

[pupina]

Hi Zach,
yeah, die cast box, shielded wire and metal jacks like in almost my all diy pedals...the strange thing is that this kind of noise doesn't exist in the beginning, i mean just after built it....i think every circuit should be quite in bypass mode when you use mechanical true bypass...right?

[d95err]

Could be a bad solder joint somewhere. Bad solder joints can cause oscillation. Could also be a grounding error. Are you using positive or negative ground? PNP or NPN transistor?

[ambulancevoice]

OC44 is pnp
are you using the same power supply you used when you first had this thing

[pupina]

right, OC44 is PnP so i use positive ground and just battery inside....in bypass mode, if i disconnect the battery any noise gently finish....that's the strange thing! i cannot understand what kind of interaction should be between battery and mechanical bypass mode...

[nebucanazza]

Is your battery fresh?

[ambulancevoice]

yeah, its starting to sound like to me, something to do with the power supply (cold joint on the battery, unfresh battery etc)
wait... the noise is still there in bypass
hmmm, maybe its the positive wire from the battery (which i assume is connected to in the input jacks ring, so when the pedal is unpluged, the power cuts out and the battery last longer)

[PerroGrande]

Make sure you have the true bypass wired correctly and that is is really bypassing the pedal completely. 

If the noise goes away when the battery is removed, then it is clear that something is happening on the pedal when it is bypassed.  Oscillation is a possible candidate.  If the pedal is oscillating when it is bypassed, and the noise is strong enough to manifest itself on the signal line, that could be what you're hearing.   The fact that it fades away when the battery is removed tells me that an active component (vs. merely loose wires) is *somehow* involved. 

A couple of things to try.

1) leave the output of your pedal plugged in to an amp with nothing plugged in to the input.  With the battery installed, try both bypassed and non-bypassed positions on the switch.  Do you get noise?

2) leave the output of your pedal plugged in to an amp.  Plug in a normal guitar cable to the input -- but -- instead of plugging in a guitar, short the input cable out (short tip to sleeve).  With the battery installed, try in both bypassed and non-bypassed positions.  Do you get noise?

In both cases, do *not* crank the amp.  If the thing is oscillating, you could do some damage.  Raise the volume slowly and carefully.  An alternative to using your amp would be to look at the output on an oscilloscope or to use an audio probe to listen.

[pupina]

you're all very kind, I'll try and do what Perrogrande suggested
thanks a lot;
I'll post the results as soon as I've done it.
Thanx again