DIY EP Booster volume problem

[WholeLottaDimitri]

I recently finished this build about two days ago and the problem is that the pedal is a little under unity gain. The pot doesn't do anything. It is perfectly clean when in bypass but when I switch it on, the volume gets lower and there is some tone coloration
The layout I used was by IvIark and it has been verified



I made no modifications to the circuit but instead so having 2 SPST switches, I have 1 DPDT on/off/on switch that switches between fat/normal/bright
All the components are the right values. The 2SC1815 transistor I used, the full name of it is 2SC1815-GR. Does the GR mean anything?
The 2N5457 transistor has these voltage readings
Q1
D: 7.67
S: 0.34
G: 0

The 2SC1815-GR has these readings
Q2
E: 2.48
C: 8.29
B: 2.94

I honestly have no idea what to do. This is my 5th build and all the other ones before that worked perfectly.
Please leave any suggestions on what to check, changed, or fix. If you haven't already guessed, this is my first post on this forum, I like it here so far.
Here are some pictures of my build:











I really hope there is a solution.

[midwayfair]

Audio probe at the drain of the J201. Do you have amplified signal? Now audio probe at the gate. Do you have a signal that is about the same as the guitar?

Pinpoint where you're losing signal, and that will help you troubleshoot.

Third row from the bottom, just to the right of the big cut, also looks like it might be bridged with the above row.

[WholeLottaDimitri]

So the first thing I guess I need to do is desolder all the wires so I can work on the solder side   

[samhay]

You can audio probe the transistor legs and the electrolytic caps without flipping the board over.

[WholeLottaDimitri]

why would I probe the caps

[WholeLottaDimitri]

Ok so I probed the drain and the gate and they both have the same volume level, That is lower than unity volume. So what does that tell me?

[samhay]

That it's not amplifying.
The gain pot connects, via the switched caps, to the JFET's source. With it out of the circuit, I am guessing that you should have ~ unity gain.
At a guess, I would say that you have the switch or pot wired incorrectly. Try temporarily placing a reasonably large electrolytic capacitor between the source and ground. If you get a lot more gain, then that's your problem.

For reference, I have been looking at the schematic here: http://revolutiondeux.blogspot.co.uk/2012/01/xotic-ep-booster.html
If this the circuit, then you can ignore this post.

Edit - or you might have a dodgy FET. The above test will help on that front, but do you have another you can try?

[WholeLottaDimitri]

So what size cap is large? and I just connect it from the power supply to ground?

[WholeLottaDimitri]

and yes I have tried a different FET and it's the same thing.
Now when you say that I might have wired the switch wrong, which switch are you talking about
And also define a lot more gain, like volume or distortion?

[samhay]

try a 10u-100u cap between the FET's source and ground - you should be able to touch the the capacitor's legs to the FETs leg and one of the 1M resistor's legs (on the ground side).
I don't know what the switches are called, but I would imagine it might be called boost.

[WholeLottaDimitri]

So would I do this with the guitar plugged in and going to the amp? I'm assuming yes

[Gus]

A j201 and 8.2k drain resistor don't make sense to me

[WholeLottaDimitri]

I tried putting a 22uf cap that touched the drain of Q1 and ground, as suggested above,...it just shorted the signal. When it was touching there was nothing coming out of the amp

[midwayfair]

I tried putting a 22uf cap that touched the drain of Q1 and ground, as suggested above,...it just shorted the signal. When it was touching there was nothing coming out of the amp

Not the drain, the source.

[WholeLottaDimitri]

When you say the source do you mean the 9v supply? So should I touch the cap to the dc power jack or maybe after the diode

[thelonious]

When you say the source do you mean the 9v supply? So should I touch the cap to the dc power jack or maybe after the diode

The source is the leg of the FET marked "S" on your vero layout image. Touch + lead of the cap to the FET's source leg, and touch - lead of the cap to ground.

[WholeLottaDimitri]

Thank you for confirming
I also really appreciate your help with this problem

[WholeLottaDimitri]

So I just tried putting an electrolytic cap that touched the source and ground...and nothing happened, the signal still stayed the same, which is just below unity volume.

[WholeLottaDimitri]

After that I was probing around with my oscilloscope, that I borrowed from my school, and I noticed that the wave form when I touched the Gate pin, Q1, looked very similar to the regular sign wave coming from the function generator, Then when I touched the Drain, the wave was the same as if it went through the whole effect. I think that answers midwayfair and his suggestion

Audio probe at the drain of the J201. Do you have amplified signal? Now audio probe at the gate. Do you have a signal that is about the same as the guitar? Pinpoint where you're losing signal, and that will help you troubleshoot.

[samhay]

It would appear that your FET is not amplifying. Is this vero layout verified?