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PostPosted: Mon Jan 31, 2022 9:23 pm 
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Hello and thank you in advance. This is my first kit build, although I've done some electronic stuff in the past. Used Kester rosin core solder. It's okay if you laugh, but I started by soldering the resistors from the top, instead of the bottom. That continued for a while. As things progressed, I finally realized that soldering from the bottom is the way to go. So if things look a bit "oversoldered" on the top, well, there we go. I have gone over the board with a 4x loupe, soldered all from the bottom, checked and rechecked. I tried to double and triple check everything I was doing before soldering. I don't see any solder bridges. The capacitors are all spaced a bit above the board, as are the transistors.

Here are my symptoms. With power supplied, when the guitar is plugged in, the LED is always on, whether the footswitch is bypassed or not. When the footswitch is engaged, changes in the level trim pot act as they should, the equal volume is more clockwise than its middle position. The bias trim pot makes no difference, except nearly all the way clockwise the volume disappears, goes quiet. The Depth knob, when fully counterclockwise, seems to add a bit of volume, or almost a slight reverb sense, but it is subtle across its range. The Speed knob changes the brightness of the LED, makes it brighter as it is turned clockwise. Not getting any tremolo at all. The guitar plays through to the amp in bypass or engaged position.

I did get the #1 pin on the footswitch hot enough to melt back the insulation on the wire.

I checked continuity on the footswitch as mentioned in a different post, with two of the lugs and two of the numbered solder points on the board, and it checked fine.

So, what do you think?


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PostPosted: Tue Feb 01, 2022 11:52 am 
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POST CONTENT DELETED--INACCURATE & MISLEADING! My apologies!! :oops: :roll:

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PostPosted: Tue Feb 01, 2022 1:44 pm 
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I have rechecked all the resistors, found one that seemed to be the wrong colors, one of the 2k2 ones LOOKED like brown red black brown brown instead of red red black brown brown, but with the multimeter it read the same resistance as all the other 2k2 resistors. I also populated the board by groups of resistors, so it came from the strip of 5. I also looked at the schematic and couldn't see any way that the LED would light in both footswitch positions, I looked with a loupe at the footswitch and did see a couple of wild strands from #2 pole, trimmed them, with high hopes, but the pedal behaved the same as before. I looked at both sides of the board around the #1 solder hole for shorts, nothing. This was done a little while ago. The footswitch seems to check out just fine with the multimeter, with poles 1 4 7 and 3 6 9 alternating between connection to the middle ones. But it sure seems like for the LED to be lit in both positions it's gotta be the switch.

I think I can use the multimeter to check DC voltage, I mean, I've checked batteries and such. So let's assume that yes, I can do that on a circuit board.

Just checked the footswitch again. I AM getting a little current flow between poles 8 & 9 when there should be none. Call it 300,000 ohms.


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PostPosted: Tue Feb 01, 2022 2:16 pm 
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Eric_Maine wrote:
I have rechecked all the resistors, found one that seemed to be the wrong colors, one of the 2k2 ones LOOKED like brown red black brown brown instead of red red black brown brown, but with the multimeter it read the same resistance as all the other 2k2 resistors. I also populated the board by groups of resistors, so it came from the strip of 5.

I wouldn't worry about that resistor. The color bands can be notoriously difficult to visually distinguish. If it measured correctly and was on the same strip with 4 others, it's the right resistance.

Eric_Maine wrote:
I also looked at the schematic and couldn't see any way that the LED would light in both footswitch positions, I looked with a loupe at the footswitch and did see a couple of wild strands from #2 pole, trimmed them, with high hopes, but the pedal behaved the same as before. I looked at both sides of the board around the #1 solder hole for shorts, nothing. This was done a little while ago. The footswitch seems to check out just fine with the multimeter, with poles 1 4 7 and 3 6 9 alternating between connection to the middle ones. But it sure seems like for the LED to be lit in both positions it's gotta be the switch.

OK, we can determine if the ground short is on the PCB rather than in the footswitch. Detach the wire at lug 2 of the switch that connects to the PCB ground trace. If the LED still stays lit all the time, the short must be on the PCB somewhere.

Eric_Maine wrote:
Just checked the footswitch again. I AM getting a little current flow between poles 8 & 9 when there should be none. Call it 300,000 ohms.

I think that's probably a red herring. Can't see how that could cause either of your problems.

Eric_Maine wrote:
I think I can use the multimeter to check DC voltage, I mean, I've checked batteries and such. So let's assume that yes, I can do that on a circuit board.

OK, I'll get back to you on that shortly. Let's see if we can solve the LED issue first.

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PostPosted: Tue Feb 01, 2022 2:24 pm 
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I do have an extra 3PDT switch available, if you think my footswitch is definitely bad because of that leak. I can replace it and try again...


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PostPosted: Tue Feb 01, 2022 2:30 pm 
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I disconnected lug 2, the LED stays on all the time still, and in both positions gets brighter and darker with the Speed knob.


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PostPosted: Tue Feb 01, 2022 3:32 pm 
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The behavior you are describing suggests that there is a short between lug 1 of the C100k speed pot and the emitter of Q5. There's a trace on the top side of the PCB that runs under the text that reads, "SPEED C100k". Do you see any points along this trace that look like it's shorting against the speed pot eyelets or the 1k8 resistor eyelets?

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PostPosted: Tue Feb 01, 2022 3:37 pm 
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I must be spending too much time bouncing from thread to thread on the forum these last few days, and am starting to make stupid mistakes (well, more of them, anyway!). I completely forgot about the fact that the LED in this circuit is tied to the trem circuit so that the LED modulates with the Speed control! So most of what I said up a few posts ago is NOT accurate, so I have deleted that content. It is NOT true that the LED is independent from the effect circuit here, or how could it flash in time with the Speed control?? "Electronic empathy"?? Geez....

It is, however, good to see that the problem is not in the footswitch, so disconnecting that wire was worthwhile. You can reconnect it now.

In the meantime, I see that Keith/byoc has jumped in and since he's forgotten more about this circuit than I will ever know, please follow his lead!

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PostPosted: Tue Feb 01, 2022 3:42 pm 
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I followed it in both directions, to the transistor on the left next to the LED, and all the way around to the #1 solder spot for the wire, down to the left of the footswitch. I don't see anything that gets close to it, there's a gap between the trace and any beginner solder artifacts like flux blobs. I am confident that trace is good. Lots of space between the trace and the 1k8 too.

Could it be flux? I didn't clean it off, and since I (unfortunately) did a lot of soldering from the top, from what I've read there is some danger to electronic parts from solvents to clean flux...


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PostPosted: Tue Feb 01, 2022 5:03 pm 
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Eric_Maine wrote:
Could it be flux? I didn't clean it off, and since I (unfortunately) did a lot of soldering from the top, from what I've read there is some danger to electronic parts from solvents to clean flux...

Interesting point and an excellent question! We have had instances in the past where there was conductivity caused by residual/thermally degraded flux and cleaning it up fixed the issue. Don't know if that's going on here, but cleaning up the PCB up in that area seems like a good thing to try. The way I've always done it is to gently scrape away the melted flux with the blade of a small screwdriver, brush off the loosened flakes with an old toothbrush, and then clean up the residual with isopropyl alcohol-soaked Q-Tips, which won't damage the board. There are three solder connections to the ground trace on the back of the PCB close to the Q5 emitter which I've highlighted on the image attached below (both front & back of the PCB). That's where I'd focus the clean-up.

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PostPosted: Tue Feb 01, 2022 6:16 pm 
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Okay, I will try that. Being who I am, I'll probably try to clean up even more, so I'll probably be reporting back tomorrow on results. Thanks a bunch!


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PostPosted: Tue Feb 01, 2022 8:28 pm 
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Whew. Multiple washing. Used a stiffish oil painting brush dipped in alcohol, then compressed air (canned air) to blow that across the board into scrap paper. Multiple times. The q-tips just weren't doing it. At least on the top side, they worked okay on the bottom, except leaving a bunch of fibers behind in the snipped off ends. The top and bottom are pretty clean, although there are still some areas of the top that might have a tiny bit of flux, but basically both are clean. I've gone over both sides now multiple times with my 4x loupe. I did notice 2 or 3 resistors that had a very slightly melted surface on one top corner, like the thickness of the paint. I've looked at the solders on all the transistors, they look okay. Because I spaced the capacitors away from the board, I don't think I could have overheated any of them. I checked all the transistor #s against the PCB #s, okay. I checked the alignment of the blue capacitors against the photo in the instructions, and checked a lot of them against the square pad on the PCB. Okay.

There was one slight change in behavior after the cleaning. Now, the Depth knob does an even transition from full volume at counter clockwise to zero volume at fully clockwise. Before only seemed to get slightly louder fully CCW, and a stable volume the rest of the way CW, if memory serves.

Continued symptoms: the LED is lit in bypass as well as engaged footswitch. In both, it changes the brightness of the LED. There isn't a hint of tremolo. Depth is now DOING something, LOL.

OKAY!! I just learned something new. I tried testing the footswitch, once again, with the multimeter. There is a short between lugs 1 & 2, but only with the current flowing in one direction. If I reverse the probes it doesn't short. Try as I might. In any case, it sure seems like either the footswitch is NG, or I made it NG. Weird. Oh, lug 2 is soldered back again.


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PostPosted: Wed Feb 02, 2022 7:17 am 
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Woke up and still couldn't believe the multimeter results on the footswitch, so I checked it AGAIN. Sure enough, there's an 18,000 ohm leak between lugs 1 & 2, but only with the negative meter probe on lug 2. With the positive probe on 2 and negative on 1, there is no reading (NOT a reading of zero ohms, mind you). I still can't wrap my head around it, as it would seem that if there is a short in the switch, it wouldn't care about positive and negative. But if the problem is in the circuit, and the switch is working right, well, then there should be no possibility of ANY current.


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PostPosted: Wed Feb 02, 2022 10:24 am 
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Eric_Maine wrote:
Woke up and still couldn't believe the multimeter results on the footswitch, so I checked it AGAIN. Sure enough, there's an 18,000 ohm leak between lugs 1 & 2, but only with the negative meter probe on lug 2. With the positive probe on 2 and negative on 1, there is no reading (NOT a reading of zero ohms, mind you). I still can't wrap my head around it, as it would seem that if there is a short in the switch, it wouldn't care about positive and negative. But if the problem is in the circuit, and the switch is working right, well, then there should be no possibility of ANY current.

You have to be very careful about making any conclusions from this behavior because of the fact that lug 1 is connected back to the effect circuit. So it's possible that there may be one or more parallel paths to ground through lug 1 that don't go through lug 2. And it's possible that you would only see the 18K resistance with the probes applied one way if the "leak" is through something acting as a diode in the circuit. Not sure what that might be, but it certainly seems possible, especially of there's something amiss in the circuit--which there obviously is, since you have no tremolo effect.

In any case, if you want to be sure that you're testing just the footswitch, disconnect the wires from lugs 1 and 2 before testing it.

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PostPosted: Wed Feb 02, 2022 12:38 pm 
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In my experience, it's best to just try to focus on one thing at a time. For the time being, you should put whatever you think might be wrong with the footswitch aside till the LED problem is resolved. If the LFO isn't working, nothing else on the pedal is going to work. And the problem with the LFO isn't in the footswitch.

The first thing we usually recommend doing is reflowing your solder joints. It doesn't matter how much experience you have, the best of us still make cold solder joints from time to time. So I'd reflow the solder around the LFO portion of the circuit at the very least (the upper right hand corner). Please do that and let us know if there was any change.

The 2M2 resistor looks damaged. Is that just superficial damage to the paint, or is the body of the resistor cracked?

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PostPosted: Wed Feb 02, 2022 4:21 pm 
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First, the 2M2 resistor got touched by a hot iron, to me, it looks like the outer coating is all that is melted. It is not cracked.

The reflow process wasn't particularly grand. Reflow is much harder than the original soldering, at least for me. Perhaps part of the problem is my old eyes not being able to focus close any more, and reflow is much more dependent on seeing carefully what's going on. So now I have more solder joints that aren't shiny, or lumpy. I guess I managed to create a bunch of cold solder joints. I went over those again. I don't think I fixed all that needed it, because now the volume when the footswitch is engaged can't be adjusted upwards to match the bypass volume. Other than that nothing else changed.

I've ordered a desoldering pump. That might help with the joints that look bad now, LOL.


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PostPosted: Thu Feb 03, 2022 11:20 am 
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Eric_Maine wrote:
First, the 2M2 resistor got touched by a hot iron, to me, it looks like the outer coating is all that is melted. It is not cracked.

The reflow process wasn't particularly grand. Reflow is much harder than the original soldering, at least for me. Perhaps part of the problem is my old eyes not being able to focus close any more, and reflow is much more dependent on seeing carefully what's going on. So now I have more solder joints that aren't shiny, or lumpy. I guess I managed to create a bunch of cold solder joints. I went over those again. I don't think I fixed all that needed it, because now the volume when the footswitch is engaged can't be adjusted upwards to match the bypass volume. Other than that nothing else changed.

I've ordered a desoldering pump. That might help with the joints that look bad now, LOL.


Tremolo modulates the volume, so if you're LFO is stuck in lower volume phase, then it would make sense that you can't get unity gain anymore. So I wouldn't worry about that too much. Just stay the course and focus on getting the LED/LFO to work.

I'm probably going to have you replace the Q5 transistor, so your desoldering pump will come in handy. You should contact sales@buildyourownclone.com and tell them I said to send you an entire new transistor set for the BFT. I don't think you need to replace all the transistors, so don't remove any of the other transistors on your PCB. I'm just going to send them to you for good measure.

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PostPosted: Sat Feb 05, 2022 8:35 pm 
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Which is the Q5 transistor? Desolder tool due in on Tues 2/8, transistors due in Wed 2/9.

Thanks again!


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PostPosted: Sat Feb 05, 2022 8:55 pm 
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Q5 is the transistor immediately under the LED.

Incidentally, the easiest way BY FAR to remove the transistor is to clip off the head and then desolder the legs one at a time, in which case you just melt the solder joint and pull out the leg with a small pair of pliers. Use your solder sucker to clean out the three eyelets and then you're ready to install the new transistor.

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PostPosted: Thu Feb 10, 2022 1:59 pm 
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Okay. I replaced Q5, I replaced the 2M2 resistor even though I thought it was probably okay. I added a 3-pin snap connector to the DC input, so I could separate the PCB from the case easily and repeatedly (LOL).

Now, the Depth knob changes the volume smoothly from higher than unity to quiet. Quiet is clockwise. At full clockwise I can hear a faint whistle-chirp with occasional quiet feedback squeak. The Speed knob still only changes the brightness of the LED from bright to dim. Dim is counterclockwise. When I touch the un-knobbed Speed pot, I hear a pop or some static from the amp. When I turn the Speed knob I hear some crackling. Not a lot, but a few pops.

The desolder pump is GREAT.

I'm actually excited about this again, now that I've got a stock of transistors, a few extra resistors, and a couple of stomp switches... just in case.

Okay, a little later. I replaced the footswitch, because I could. I was very careful to NOT overheat it but still make good solder connections. I checked the disconnected old footswitch, it tested fine. On powering up the unit, it worked the same as above. Also, I re-flowed a number of joints on the bottom of the PCB, and cleaned it quite well with alcohol.


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PostPosted: Fri Feb 11, 2022 11:38 am 
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You have a problem in the LFO. Maybe you still have a cold solder joint in there. Maybe there's a damaged component. Other than telling you that, there's not really much else we can do to help you. There's no tests you can do with a DMM that will help pinpoint the problem.

The LFO consists of Q5, C13 ~ 18, R20 ~ 23, VR1, D1, and the connection to ground via SW1a. We can send you replacement parts and you can try replacing them one at a time till it the LED starts blinking.

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PostPosted: Fri Feb 11, 2022 11:49 am 
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Okay, thanks. I will see what I can come up with looking at those parts of the circuit, and their solder joints. Hopefully I can translate the schematic into the PCB!


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