Son Of Ben Q2 Biasing Issue

I built the Son of Ben and used what are probably not genuine J201's. I got the biasing close but not quite on Q1, however, Q2 and Q3 were in the low 3v range. The pedal sounded good, but I was hoping I could make it better, so I ordered the surface mount J201's. I installed them today and got Q1 and Q3 bang on at 5.1v and 4v but now I cannot get Q2 to drop below 9v. With the trim pot all the way down Q2 reads 9.10v and with it all the way up it reads 9.15v. What have I done? Help!
 
So, I solved the mystery. I messed up my board desoldering the through-hole J201 in order to instal the surface mount ones. Thanks for your help. I guess I need to order a new board and start desoldering all my parts.
 
So, I solved the mystery. I messed up my board desoldering the through-hole J201 in order to instal the surface mount ones. Thanks for your help. I guess I need to order a new board and start desoldering all my parts.
Benny profane is right. Plus you might damage your components if you are new to soldering and you desolder them.
 
Thanks so much guys. I am new to soldering and to electronics in general. I messed up the first pad trying to desolder the original j201 and then messed up the other two trying to get the new j201 out. How would I go about making a jumper? Sorry if this is a stupid question. This is all new to me.
 
If it's Q2 that's correct you'd only need to solder a jumper on the damaged pads not all

I usually do it on the solder side of the board simply tin the ends of your jumper and solder/ melt them onto the solder that's already there and direct to the component leg where the pads a goner

Obviously you'd need to continuity check to make sure you solder to the correct side e.g. R9 you'd want to solder to the side not connected to trim 2 along to Q2 drain pin or C6

Which pads have you damaged left, middle or right or a wee combo

If you use this image you can see some traces so you know from the J201 pinout left to right is D, S, G you can also see how the SMD J201 connects and where they connect to resistors etc

20211106_131502.jpg 20211106_132133.jpg
 
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If it's Q2 that's correct you'd only need to solder a jumper on the damaged pads not all

I usually do it on the solder side of the board simply tin the ends of your jumper and solder/ melt them onto the solder that's already there and direct to the component leg where the pads a goner

Obviously you'd need to continuity check to make sure you solder to the correct side e.g. R9 you'd want to solder to the side not connected to trim 2 along to Q2 drain pin or C6

Which pads have you damaged left, middle or right or a wee combo

If you use this image you can see some traces so you know from the J201 pinout left to right is D, S, G you can also see how the SMD J201 connects and where they connect to resistors etc

I did the full trifecta and screwed all three of them up. I want to make sure I do this right so I am going to ask what is probably an obvious question, just not obvious to me. Looking at the PCB picture posted would it be the top side of R7, R8, and R9? And would it be the positive side of C6? I think I am reading the schematic and the picture correctly, but I am not in any way self-confident. Thanks for your help!
 
Can you provide a picture of your board? Which pads exactly are damaged? If you were able to successfully install the SMD parts, the only connection that might be damaged by destroying the through-hole footprint would be between R8 and the anode of C5.

The previous posts have good information about the connections you'll need to confirm / jump. Before running jumpers, test for continuity.
 
Can you provide a picture of your board? Which pads exactly are damaged? If you were able to successfully install the SMD parts, the only connection that might be damaged by destroying the through-hole footprint would be between R8 and the anode of C5.

The previous posts have good information about the connections you'll need to confirm / jump. Before running jumpers, test for continuity.
Thank @music6000 for the help; the picture makes things really clear to me. I only screwed up Q2 so I should just need to run the jumpers for this section. As you can see in the photo my desoldering attempts really jacked up the board.
 

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Oh wow. Are the pads absent on the other side of the board too? Check continuity between the all of the Q2 circles as noted in @music6000's post above.
Yeah, pretty much just gone. I took out the through-hole J201 and messed up the drain. Then, trying to get out the surface mount adapter J201 I screwed up the other 2. To be honest, I have a cheap soldering Iron from Amazon and I was getting really frustrated. Plus, I'm not yet good at soldering or desoldering. It's was the perfect storm for screwing up the board 😂
 
If only Q2 Through Holes are damaged, this should work , Run Blue Jumper with Insulated wire from Solder side (Back) of PCB Board :
I feel like a child that keeps asking the same question over and over, but I want to clarify. I should link up the yellow and pink, and then wire the blue as you have shown (R8 connected to the J201 and C6). Is that right?
 
I feel like a child that keeps asking the same question over and over, but I want to clarify. I should link up the yellow and pink, and then wire the blue as you have shown (R8 connected to the J201 and C6). Is that right?
Check for continuity between the circles and verify that the SMD part is installed and making connections. The only jumper you’ll probably need is the light blue line between R8 (1k) and C5 (10u).
 
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