Build Your Own Clone Message Board

I just finished the FET preamp and two weird things are happening. When bypassed, it is sucking all the tone from my Les Paul. When engaged it works beautifully, but, when you engage the effect the LED flashes once and stays dark while the effect is on. Any ideas

Thank you,

Paul D'Amato

The best way for members to troubleshoot is if you post very clear pictures of the board, soldering, connections, etc. Do you have access to a camera?

I read the FAQ and thank you, but, before I rip this thing apart ( it's not a simple task with this design) to take pictures I figured I would ask the question since this is a relatively simple issue that others may have run across. I do not have a problem with my wiring ( of the footswitch ) since I have sound always, but I do have serious loss of tone on my clean sound when the pedal is bypassed and this has never happened on any of my other builds.

Paul

Take your car to a mechanic the next time you have car troubles. Describe to him what the problem is but do NOT let him look under the hood and see if he can help you with the problem.

Your pedal build could have the exact same symptoms as a dozen others but that doesn't mean it's the same problem with each build. Without some high quality photos with lots of detail for us to see there isn't a whole lot we can do to help.

Really ? You couldn't even say something to the effect of " try changing the LED because other people in the TriBoost forum have had similar problems and installing a new LED solved the issue" ? Or, " check to see that your LED is wired correctly, longer lead to square hole" ? I didn't expect my first post to be answered by a smart ass moderator without offering an ounce of help....hell, it took more of an effort for you to type what you did than to offer a quick answer. I've built over 40 pedals and every one of them has fired up on the first try...it just so happens that this one DID come with a faulty LED .

Thank you for your help, I'll call a friggin' mechanic next time . Save your advice for the children on this forum.

Ok, how about a smart ass member who has been helped numerous times by said smart-ass moderator.

You did not provide the information needed to get help. You even read the instructions on how to get help and still ignored it assuming that doing so would result in you not doing the work. So how about this:
Your problem could be any of the parts on the board or in the wiring that would cause this problem. Since you said it has "tone suck" when bypassed, then that means there could be something wrong with your footswitch wiring. Since this is true bypass, the only way you could be getting tone suck is if the circuit signal is bleeding into the bypass. THE ONLY PLACE IN THE PEDAL WHERE THE BYPASS SIGNAL AND THE EFFECT SIGNAL ARE CLOSE IS AT THE FOOTSWITCH.
As for the LED, you may have put the wrong resistor in the CLR position in the board (which could cause the LED to die), of course, without a picture we can't tell. OR you could have a short somewhere, but without pictures WE CAN'T TELL.
-P

Oh yes and as for the "I've built 40 pedals". Even after Thousands of pedals made by manufacturers, a mistake is made at times.
-P

Paul, I think you're over-reacting to the point that Stephen was making. We almost always ask for photos because it is pretty unusual in our experience that the cause of a pedal problem can be determined from only a verbal description of the symptoms. Another forum member made the initial suggestion to post photos, and when your response indicated no immediate intention of doing that, Stephen just tried to make an analogy to illustrate the importance of photos to the troubleshooting process. I really don't think there was any intent on his part to be a "smart ass" about it.

If your pedal is tone-sucking in bypass, then you have something more serious going on than just a potentially defective LED. Tone-sucking behavior generally arises when some point in the effect circuit is shorted to the input or output signal paths before or after the footswitch. But, again, we'd really need to see photos--front and back of the PCB, plus all the jack and switch wiring--to be able to see how this might be occurring.

Damn! Somebody needs to take a Valium and calm the hell down.

Done and Done, sorry Stephen.
-P

So .......

Is the pedal fixed yet or not?

From just your description, as has been pointed out already, it does sound like a basic switch wiring error.

Apart from sharing the power rails the LED circuit SHOULD be separate from the rest of the pedal. It is a VERY simple circuit - just a switch, a LED and a resistor.

If the LED flashes it could be a faulty switch, an intermittent joint, or you have somehow managed to connect the LED to one of the pre-amps capacitors. If the LED is in backwards it will not flash (some of the white silkscreen markings on BYOC PCBs show the flat on the LED in the wrong direction). The square solder pad marks the positive connection which is the longer lead or anode on the LED. I have myself had a LED not lighting because I followed the silkscreen and gone nuts for a while because I couldn't see why it did not light.

One of the main features of the BYOC designs is true bypass, That means that when bypassed the input jack is wired directly to the output jack and in that case there is nothing there to tone suck. If If you get tone suck in bypass it is either because the pedal is doing such a brilliant job that your normal tone sounds bad in comparison, or your switch and/or jacks are wired incorrectly.

Large clear photos of your build would allow other members of this forum to check these points visually and provide you with a more certain course of action.

Incidentally if you want to realise the high input impedance of which this circuit is capable (I believe high input impedance is one of the original design features) you should either remove the pop stopper resistor R101 470K (and put up with any switch clicks) or replace it with something like a 10 Meg.