Black Tiger Boost build issues now possibly made worse

FleeRemi

Member
So i'm working on my first ever build, a pedalpcb Black Tiger boost. I finished last night and it worked decently well but had a weird "farty" sound to the signal like something on the board might not be functioning correctly. I decided to reflow all of the connections on the components of the pcb, and now when I engage the switch, the pedal has little-to-no signal. Signal is perfectly fine in bypass, and if i turn the knob down all the way, the dry signal will come thru in a bypass-like-manner.

What did i screw up? Worried i may have fried a capacitor or possibly the 4558 chip. Including a bunch of pictures that may or may not be of help.

Thank you in advance for any help!!
 

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Yeah, there's something not right. You should begetting around 9V. Check your DMM to make sure your reading voltage.
Okay so it turns out I was using the wrong spot on the multimeter dial (9v but it was for battery testing I guess?). Figured out which one was right and here are my new voltage readings:

Pins
1 - 1.44
2 - 3.54 - 3.55
3 - 2.36 - 2.37
4 - 0
5 - 3.71 - 3.73
6 - 3.82 - 3.83
7 - 3.83 - 3.84
8 - 8.50 - 8.51

DC Jack/Power Supply - 9.33

I'm trying to do the continuity test (set it to the symbol listed, touching probes to both sides of the component), the buzzer sounding means the component is faulty right? I have one resistor buzzing, specifically R1.
 
Link to Black Tiger Boost schems :


I didn't check the whole thread, but i see there are some doubts about the power supply readings.

Is this the one ?

View attachment 67603

In this case, there is no way it reads 23V, and you won't find any switch, this power supply can only provide 9V DC.
I have 2 or 3 of those, and they always read 9.45V or so.

23.5 what ? is there a V symbol for Volts?

You need to set your meter on DC voltage reading (Direct Current and not Alternative current), black probe on ground (any ground point in the circuit), red probe on pcb 9V+.

DC current symbol on your meter :

View attachment 67607

I also understood there are some doubts about a fried 4558 ? They are quite sturdy, and usually don't get overheated easily.

Chris is right (about this topic), i totally agree with reply #5.

If you have an other gain effect, you could try it with this chip, see if it works or not. 4558 are compatible replacement for most dual op-amps, like TL072, etc. which are often found in various guitar effects.
They are quite cheap and very common, so you can also get a new one to avoid any doubts about it.

Edit : i just noticed that the 4558 isn't socketed. It could be tricky to unsolder it. I would check carefully the rest of the circuit before removing this chip.

I'd suggest to shorten these legs, to avoid any short with the enclosure. Looks like they are just as high as the status led :
View attachment 67610
If i may, i'd say that your soldering technique is quite interesting, i can see some beautiful shapes, but these soldering pads are somewhat irregular. Looks like a few pads, located toward the middle of the pcb, are maybe a little bit light on the solder ?

You could also clean the tiny spaces between pads with your Soldering Iron (moving quickly), to avoid shorts.

On a side note, it looks like the Led is stuck to the board. It might be hard to make it fit in your Plastic Led Mounting Clip ?
Yeah I saw you mention last night about the trying the chip out on a different pedal, and was thinking de-soldering it would be a real pain. I'll check out the pads to see where some extra solder could be needed and i'll trim those wire leads you mentioned too. The diagram of the drill template in this schematic was off, so my led doesn't actually reach the spot its supposed to be in anyways (I also didn't have a mounting clip for it) so I was just kind of ignoring it at this point until i can remove and replace with a wired one (with mount), and drill the hold a little more, just worried about ruining the design on the front near that spot.
 
If you touch two separate points and the buzzer goes off that means those two points are connected. So if you touched both ends of a resistor and it goes off either the resistor is toast or there is a short somewhere connecting those pads.
 
If you touch two separate points and the buzzer goes off that means those two points are connected. So if you touched both ends of a resistor and it goes off either the resistor is toast or there is a short somewhere connecting those pads.
Damn, the joints looked fine/separated so as not to cause any shorts, reflowed em just to be sure and still getting the buzz, resistor must be bad. That shouldn't be too hard to desolder/remove right? Open to any helpful tips anyone might know
 
Ok, those voltages seem a little more realistic. R1 should be a 1M resistor, if you are touching both ends to that resistor to test continuity, you shouldn't get a beep, but make sure you are testing it correctly. One end of that resistor is connected to ground, if you touch that one and the other test lead is touching ground anywhere, it will beep. Just make sure you only touching one test lead to each side of the resistor and nothing else.
 
Ok, those voltages seem a little more realistic. R1 should be a 1M resistor, if you are touching both ends to that resistor to test continuity, you shouldn't get a beep, but make sure you are testing it correctly. One end of that resistor is connected to ground, if you touch that one and the other test lead is touching ground anywhere, it will beep. Just make sure you only touching one test lead to each side of the resistor and nothing else.
I think i'm just touching the leads. Specifically doing it toward the bend at the top so as to avoid the pad.
 
The footswitch just needs to be in the "active" state to measure, it doesn't need to be powered up.

Apply power, press the footswitch so that the LED is lit, then disconnect power (without clicking the footswitch again).

or

Check for continuity between the tip lugs of the Input / Output jacks. They'll have continuity when the pedal is bypassed.
 
Check continuity. Engage the switch. Test continuity again. If it beeps one way and not the other then you don't have the short, it was just the switch connecting it to ground like Robert said.
 
The footswitch just needs to be in the "active" state to measure, it doesn't need to be powered up.

Apply power, press the footswitch so that the LED is lit, then disconnect power (without clicking the footswitch again).

or

Check for continuity between the tip lugs of the Input / Output jacks. They'll have continuity when the pedal is bypassed.
Check continuity. Engage the switch. Test continuity again. If it beeps one way and not the other then you don't have the short, it was just the switch connecting it to ground like Robert said.

Yep, engaging the switch made the beep go away. So at least there isn't a short, but unfortunately doesn't solve my problem. I guess I'll try adding some solder to some of the lighter-soldered-pads like the other user said and see if that helps?
 
Alright well I reflowed all joints, added solder to some of the lighter ones, and the problem still persists (little-to-no signal; fine in bypass, and if i turn the knob down all the way, the dry signal will come thru in a bypass-like-manner).

Guess i'll be shelving this one for now, reluctant to start the next one but not much else I can do at this point.

Thank you everyone for all of your help, I still very much appreciate it.
 
I double checked your resistor color codes against the build doc and they're all in the correct spot. I'm not sure what else it could be. You could make an audio probe and see where the signal quits in the circuit to trouble shoot it more. I understand shelving it for now though. I would also turn the heat up on the soldering iron. I don't know that the joints are cold, but the solder is very dull looking and not shiny. What solder are you using?
 
I double checked your resistor color codes against the build doc and they're all in the correct spot. I'm not sure what else it could be. You could make an audio probe and see where the signal quits in the circuit to trouble shoot it more. I understand shelving it for now though. I would also turn the heat up on the soldering iron. I don't know that the joints are cold, but the solder is very dull looking and not shiny. What solder are you using?
What temp would you recommend? I'm using 63/37 solder.

How would I go about doing the audio probe?
 
Audioprobe :


Soldering Iron temperature :

I'd say somewhere between 370 and 400 °C ?

I use 0.56mm soldering wire, and 380/390 °C is all right.

You might have to do some tests, to find the right setting. If it's hard to put the solder on the pad because it doesn't flow smoothly, you should increase the heat.
If there is lots of smoke, lots of dark residues around the pad, and the solder looks half-burnt, you should decrease it.

High temperatures are especially dangerous when soldering toggleswitches and footswitches, if you stay too long applying some heat, they can melt quickly and prevent the part from working correctly.

You are supposed to clean the tip of your iron on some almost-dry sponge quite often, when the tip is dirty.

Edit : You could also clean the pcb as much as possible, using an old dry toothbrush. Let's remember that even the slightest piece of hair can create a short.

IMG_8776.jpg

I would also do some continuity tests between every ground points in the circuit, including jacks and DC power jack. Ground is a network, they are all supposed to be connected. Then i would do some continuity tests on the wiring (footswitch pads, pcb footswitch pads, jacks). They are usualy the most obvious suspects.

Check each wire pads carefully, sometime a tiny piece of wire missed the hole and is shorting the next pad.

Did you use some bubblegum to install the DC power jack ? May i ask what flavor ?
 
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What temp would you recommend? I'm using 63/37 solder.

How would I go about doing the audio probe?
Ok, lots to go over here, but let's start with the temp. I solder at 680F (not sure what that is in Celsius) with 60/40 rosin core solder, which seems to work fine for me. Rarely have I fried anything, and I don't usually have any questionable soldier joints.

Ok, on to the audio probe. You just need a probe that has a capacitor in series with the probe. The value isn't as as important as the voltage rating. Personally I use a .1uF at 400V. You just want to make sure you have a high enough voltage to handle the circuit you are testing.

You can take a guitar cable, cut off one end, and connect the center to your capacitor, an then the capacitor to your probe (anything conductive and pointy enough to touch a pad without touching anything else - can be a probe, can be a nail - just needs to be sharp and pointy). The shielded part of the cable will connect to ground, so soldier on an alligator clip to something that you can insert into one of the ground points on your enclosure (assuming that you are testing your board inside an enclosure). Otherwise, you just nee some way to connect it to ground.

Once you connect the probe to ground, plug it into an amp (I prefer to do this with the cheapest amp I have on hand (can be anything, but I don't recommend plugging it into a high dollar guitar amp (I use one of those $10 amps off of Amazon, so if I fry it, I'm only out $10).

Next you want to put a tone across the pedal, I use a tone generator, but you can use a guitar, or for convenience, you cn use a looper pedal. You can even use your phone or computer, if you have a way to send the signal to the input of your pedal.

Once you've managed all of that, you simply touch the probe to various points in the circuit (I generally start with the schematic and work my way through the circuit). You should hear the guitar tone from the input through different points on the circuit. When you get to the point where you hear something funny or the sounds drops out entirely, you have found your problem.

If any of this doesn't make sense, please let me know. I'm here to help.
 
Well hold on a second, good people.

OP didn't say it was a faulty circuit, they said it was a farty circuit. Looks like full CCW is a 0db boost, so it should be very similar to the bypass signal and that's by design. It actually could be working, but we are ignoring two parts of the system.

I'd be curious to know what is your signal chain and amp or multi FX you are running the pedal through. I've run some pedals that sound great in one amp and really atrocious in another. I've also built some boosts (color sound) that at max completely overload the amp and make it sound like what could be thought of as farty.

Is there any level at which it sounds good? Is it mostly the low end that sucks? Have you listened to/watched demos to see how similar yours is? Tried it in different amps?
 
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