Speaking of weird...

[alphadog808]

So, I've been having whine issues with my current builds(Timmy and Zendrive).  What I'm noticing is that it happens when all the knobs are maxed(makes sense) but why would it whine when NOTHING is plugged into the input?

And I mean just the cable is enough to stop it; whether the input cable is plugged into a guitar or not, it doesn't matter, it stops the whine.

I figure if anything, the pedal would whine more with the input cable plugged in, due to more cabling, etc.

For kicks, I tried using insulated wire between the input and output jack to the dpdt switch, same issue.  

Anyone have any ideas?

[Beaker]

Ok, one pedal could be build issues, but two different pedals with the same symptoms suggests an external source.

Now is the time to check EVERYTHING in your chain.

#1. Are you using a power supply or batteries? If you are using a power supply because you don't have room for a battery in the enclosure, rig up a battery to a spare power supply connecter and try that. If the whine goes away it is probably your power supply at fault.

#2. Try a different amp and see if that makes a difference.

#3. Try plugging your amp into a different ring circuit in your house - it could be noisy power or an earth issue in your house.

[alphadog808]

Beaker, I appreciate the help!  In response to your suggestions

I have usually been testing with a power supply.  When I was troubleshooting, I hooked up a 9v battery to it and it did the same thing; since then I haven't tried again, maybe I should.  At another point, I did try hooking it up to another wallwart, same problem.  

I have tried 2 different amps, same problem.

I tried testing it in another part of the house, same problem.  If it was on the same ring tho, I'm not sure.  Maybe I'll have to try testing it in yet another room.

I'll retry the tests and get back to you.

[alphadog808]

I appreciate the help, Beaker.  In response to your thoughts...

1) I am using a power supply.  I did test with a 9v(just clipped the leads to the battery) and it was the same.  Note, the battery voltage was low(I think it was showing 5.xV) so it was pretty weak.  Maybe I'll try a new battery.

2) I have tried 2 different amps, same prob.

3) I have plugged into a different room, same prob.  I'm not sure if it was on a different ring, now that you mention it.  I'll have to retest.  Also, when I tested it, I used a headphone rather than an amp so I didn't have to lug it around. I'll test it again in a different room as weel.

Thanks again for the help!  I'll retest and post my results.

[alphadog808]

I had a weird thought; could it be possibly tied to using a super bright LED? I've been using these.

http://www.smallbearelec.com/servlet/Detail?no=334

It's high brightness, and yes, even with the 220K resistor, it's PLENTY bright; like you can't look at it straight on with it hurting your eyes...

[alphadog808]

so, an update...

So I'm not very smart, or very good, but I am tenacious   With some advice from another forum, they mentioned the input being too high impedance causing the whine.  they suggested adding a cap on the input.

So...I tried a cap on the inputs and it didn't work...tried a few configurations and sizes(what I had available), no dice.  not sure I even wired it up right.

I then thought, let's try a resistor.  

So I put a 510K ohm resistor into the circuit.  One side on the input jack, and the other on ground.  It seemed a little better.  So I added another 510k in parallel.  A little better!  I then added a 3rd one and the whine went away completely!  

So...my question is...what did I do?  And is it harmful to tone?

[Beaker]

I'm still a liitle unsure about your problem - are you saying that you can hear the whine through  the amps, speaker, or only when you are using headphones? What are you plugging the headphones into - the amp headphone socket?

[alphadog808]

Sorry if I wasn't clear.  I can hear the whine through any output.  I only plugged in headphones to the pedal output when I tried to test the pedal in a different room; I was too lazy to lug the amp around.

I should mention that the whine happens when everything is on full and I turn the tone or treble cut back and forth.  There seems to be a sweet spot when the whine happens as I turn the knob.  On full, no problem, turn a bit too much ccw no whine.

So, it seems that putting a 100k resistor between the input jack and ground stop the whine.  As I posted earlier, I started at 510k, and kept adding 510ks(that's all I had) till it stopped.  

I was told it was bad to put the resistor on the input jack, as it will be in the chain when the effect is bypassed; makes sense.

I read that since my test had the 100k resistor running in parallel with the 2.2M or 2M resistor on the board(depending if it's timmy or zendrive) I might as well just take of the the onboard resistor and put the 100k on there as running them in parallel is 95K.  

So...I'll see if I can swing by and get some 100kish resistors and put um in and see how it sounds.  Hopefully it doesn't affect the tone too much.  

[Beaker]

Ok that clears a few things up, but I'm still convinced that the CAUSE of the hum is external, and not an issue with your builds.

I would be looking for the usual suspects such as strip lights or dimmer switches that can generate an unbelievable amount of noise, as well as things like your computer or laptop power supplies and monitors.
All these things generate radio frequencies - the whine you are picking up and can dial in at the sweet spot.

Rather than modifying your pedals to reject this noise, a good place to start would be to get a RF filtered power strip - the sort used to plug plug computer equipment into, and put that between your amplifier and the wall socket. These can do wonders for stray radio signals.

[alphadog808]

Beaker, you are probably right, but I am was really beginning to lose it over this issue.  That being said, I ended up soldering in 120K resistors on the board and everything is fixed.  I didn't do alot of loud testing(I'll probably try tonight) but so far, it sounds fine.  

If it happens again tho, I guess I'll have to really try some cleaner power.  What bothers me tho, is that my other store bought pedals have no issues with the same power and it still whines with a 9v battery, so that removes house power being an issue.

[Beaker]

"What bothers me tho, is that my other store bought pedals have no issues with the same power and it still whines with a 9v battery, so that removes house power being an issue. "

Sorry alphadog but no, it does not remove house power as a potential issue. All it does do is suggest that the store bought pedals may have better grounding and/or power filtering than your home made ones.

My son had a home recording studio in my cellar until he moved out recently, and I know that certain lights on, or certain appliances on in the house while he was trying to record, was going to cause audible hum on the recordings.

There is one more possible build issue that may be a cause however. Make sure you separate your pedals power wires from your signal wires as much as you can. This can help reduce hum and squeals.