2 in 1 help

[jwyles90]

Hey all,

I just finished putting together a 2 in1 build today and it’s giving me some trouble. I’ve got a Greengage OD and Muffin Fuzz (Green Russian specs) in there. The Greengage side of things is working fine, but when I turn on the fuzz side I’m not getting any kind of signal. When I turn the tone knob I can kind of hear this weird like, whooshing sound as I turn it but otherwise nothing is happening. I took an audio probe to it and was able to hear my guitar when I touched it to the “In” section of the 3pdt, as well as R1. After that I lost the signal.

 

[jwyles90]

Accidentally hit post before I could upload pictures. Sorry!

 

[Mcknib]

Did you try reflowing R1 solder joints

 

[jwyles90]

Did you try reflowing R1 solder joints

Should I reflow R1 if I was still getting my signal when I put the probe on there? I couldn’t hear anything when I touched it to R2 and the solder joint looked a little suspect on that one, so I’m in the process of resoldering that one. I can give R1 a go too though

 

[Mcknib]

Sorry I thought you meant you lost signal on one side of R1 reflow whatever pad you loose signal on

Make sure you're getting a good connection with your audio probe, probe on the component leg / pin rather than the solder pad

R2 you should only get audio on the side that doesn't go to ground probe the base of Q1 to double check that's where audio stops

 

[jwyles90]

Sorry I thought you meant you lost signal on one side of R1 reflow whatever pad you loose signal on

Make sure you're getting a good connection with your audio probe, probe on the component leg / pin rather than the solder pad

R2 you should only get audio on the side that doesn't go to ground probe the base of Q1 to double check that's where audio stops

Yea I used some new solder on this one initially and I'm not a fan of it. It was doing this weird thing where it would kind of glob up sometimes and when I would go to reflow it wouldn't heat up enough to start flowing. It would just get like, pushed around and form new shapes without going through the hole itself. Never had that happen before with other solder, and I bought a roll of Kester solder and that stuff works great.

I ended up having to cut the R2 resistor out entirely, and am now having a hell of a time trying to clear the pads of solder before putting a new resistor in

 

[Robert]

I ended up having to cut the R2 resistor out entirely, and am now having a hell of a time trying to clear the pads of solder before putting a new resistor in

Add a little bit of your good Kester solder to the pads, then try to desolder.

It sounds counterproductive but it gives a bit more surface area for heat transfer and also contributes a small amount of flux.

 

[jwyles90]

Add a little bit of your good Kester solder to the pads, then try to desolder.

Good call, I'll give that a shot!

 

[jwyles90]

Add a little bit of your good Kester solder to the pads, then try to desolder.

It sounds counterproductive but it gives a bit more surface area for heat transfer and also contributes a small amount of flux.

So I swapped out the resistor and reflowed a couple of the pot joints that looked like they needed it, plugged it back in and I’m still getting nothing. My guitar signal goes through when it’s bypassed but when the fuzz side is engaged I’m not getting any kind of signal at all. I’m feelin pretty stumped at the moment

 

[Mcknib]

Bypass signal tells us your jacks are ok you'd get that regardless of whether it's powered or you accidentally put your in to your out etc

It just sends audio straight from your in to out jack via the 3PDT obviously completely bypassing the circuit

If you get audio into the circuit your 3PDT switchings ok

Probing just tells you your problem area as you know, not what's faulty if it goes through both sides of R1 you'd check C1 and so on

You'd also visually check for solder bridges etc

 

[jwyles90]

Bypass signal tells us your jacks are ok you'd get that regardless of whether it's powered or you accidentally put your in to your out etc

It just sends audio straight from your in to out jack via the 3PDT obviously completely bypassing the circuit

If you get audio into the circuit your 3PDT switchings ok

Probing just tells you your problem area as you know, not what's faulty if it goes through both sides of R1 you'd check C1 and so on

You'd also visually check for solder bridges etc

Thanks for your help with this! I'm going to go through and triple check all the solder joints and wiring spots in the next few days and try to reflow as much as I can.
I thought maybe it had something to do with the transistors being bad since no sound at all was something that happened when I forgot to socket a couple in previous builds, but after swapping them out for new ones that didn't fix it either. I'm hoping it's just a bad solder joint somewhere and not a faulty resistor or something like that that will take forever to identify

 

[Mcknib]

It will be something simple like a dry joint it usually is

From your probing it appears signal isn't getting to.your transistor if it stops at R1 so hopefully just a poor connection / dry joint

Does signal actuall go through both sides of R1

 

[jwyles90]

It will be something simple like a dry joint it usually is

From your probing it appears signal isn't getting to.your transistor if it stops at R1 so hopefully just a poor connection / dry joint

Does signal actuall go through both sides of R1

Ok so I went through and reflowed as many solder joints as I could on the backside, still not getting anything. I’m getting signal on both sides of R1, but it’s considerably quieter on one side compared to the other. I’m not getting any signal from Q1 though. I just checked the transistors with my DMM and they all read around 4.5v, except q4 is around 3.6v

 

[Mcknib]

I'm taking it you've used 2N5088s

Make sure they're seated securely in their sockets

 

[HamishR]

Couple of things - The joint of the output wire at the jack is a bit messy - you don't want plastic getting in your solder joint. But obviously it's working if you're getting a bypass signal.

My main area of concern would be the transistor sockets. I have always had issues with those. Why not just solder the transistors directly to the board?

 

[jwyles90]

Couple of things - The joint of the output wire at the jack is a bit messy - you don't want plastic getting in your solder joint. But obviously it's working if you're getting a bypass signal.

My main area of concern would be the transistor sockets. I have always had issues with those. Why not just solder the transistors directly to the board?

I’ve always just put sockets in there, I like the idea of potentially swapping them out for a different types. I’ve never had issues with socketing transistors before but if that’s what’s causing this I might have to rethink that.

 

[jwyles90]

I'm taking it you've used 2N5088s

Make sure they're seated securely in their sockets

Yea I feel like if push on them any more they start to bend, but q1 does seem a little wiggly