Crybaby 9v 535Q no boost

[Texasbluezman]

I have this 9v crybaby 535Q. The wah effect works great, but the boost doesn’t. It has these stupid SMD components that I’m definitely not gonna mess with. But I was wondering if y’all think the actual boost switch might be bad? That’s probably the only thing I can think of, but I wanted to ask her to see if that’s happened to anybody else. I like this pedal because it has a solid chrome enclosure. I’ve never seen these before. I actually bought it to mod, but didn’t realize it had the SMD components. Thanks in advance.

 

[jessenator]

Have you tried manually actuating the switch (not the red stem)? I have one of these and the stem can be wonky.

If not you could try taking the board out and bridging the pads with some tweezers to check if the switch is truly faulty.

Also did you adjust the boost level pot on the side by the variable Q pot? I think at CCW it's unity so there won't be any boost.

 

[Texasbluezman]

I pulled the red stem out and worked the switch. Nothing changed. No boost.

I’ll check the pads with a jumper when I get a chance.

Yes I turned the volume up and down and nothing.

I appreciate you getting back with me.

 

[Sturdag Lagernathy]

According to a schematic I found online, the boost is part of the output buffer, so if you have a unity output, the circuit is probably ok. The switch throw selects between a 10M resistor, and the 500k boost pot. It connects to the inverting input through an 11k resistor and a 4u7 electro cap. I hope that helps something...

 

[anevilspar7an]

I am not sure that schematic is correct, I would like to ask OP to count all resistors, and capacitors (separate the electrolytics). Write all the codes on the resistors down and use an SMD decoder to get the values and then cross-reference with the posted schematic to see if it lines up. Bonus points for using a continuity tester, DMM or otherwise, to go point-to-point between each part. Don't forget the rotary switch since it has SMD components as well.