Simple Booster

[madstayen]

I checked that. If I put my ground test lead on the black wire, and V+ lead on the red, it reads 8V9, which is correct. If I swop them, it reads -8V9, which is wrong. Right?

[Hemmel]

I'd actually first check that the DC socket is wire the right way round: I've not used that type before.

I agree. It's kind of hard to tell but it seems that the + wire is connected to both top and bottom-left lugs (as seen on the "DC jack" picture. I'm not sure which of these is disconnected when a jack is inserted, but if you don't have a battery then I'd suggest you connect the red wire to only one of these lugs...

[madstayen]

That's why I bridged it, don't know which one to use, too lazy to figure out, I guess. But both of them is V+, I checked that.

[Hemmel]

I checked that. If I put my ground test lead on the black wire, and V+ lead on the red, it reads 8V9, which is correct. If I swop them, it reads -8V9, which is wrong. Right?

Actually, that's correct ! The ground test lead is considered your "reference" lead. Let's call it 0 (zero). Putting the ground test lead on negative side and V+ lead on positive side will show ~9V because there is ~9V more on the positive side than on the negative side. When you reverse the leads, your reference (zero) goes on the where there's ~9V more than the other side. So then your V+ lead touches the side where there's ~9V LESS than the other. Thus, - (minus) 9V.

That's why I bridged it, don't know which one to use, too lazy to figure out, I guess. But both of them is V+, I checked that.

It's true, both of them are V+ but one of them gets shorted out when a jack is inserted. You have to find out which one gets shorted, and connect your red wire to the other one.

[Hemmel]

Ok so according to the bottom part of this :



you should connect ground to lug #4 and V+ to lug #3. Lug #2 is shorted when a jack is connected. The diagram is on the bottom right of the image.

[madstayen]

This is how it works. I disconnected the one on the side (the one that gets shorted out). Still making that noise though.

[madstayen]

RE: Ghetto probe
I figured it out. I got the bypassed signal, with half the amount of buzzzzz. Touched the lead at C, No buzzz. Toched at B, Half the amount of buzzz. Touched at A, same buzz, different pitch.

[Hemmel]

If you're still getting a buzz while bypassed, then it's not coming from the circuit. It may be RF coming in the long wires you're using. Could you connect shorter wires ?

[madstayen]

http://img843.imageshack.us/img843/6023/uhyufseixzfeghxrxaeudw.mp4
Here is a link to the buzzz sound. I recorded it.

[peterg]

It sounds like a grounding problem.

What is the out jack's orange and white wire attached to? It should be to ground if not.

You may have the jack wired wrong. I'm not that familiar with the jack you're using but you might want to look into it.

FYI. The Circuit you've made is an Electro Harmonics LPB.

[peterg]

...also could be your wallwart and/or it's polarity.

Try disconnecting the power jack and solder with wires to a battery jacks wires. If that fixes it then the issue is with the power jack.

[nocentelli]

+1 to shorter leads - They look massive, and anything they pick up will be boosted when the circuit actually works.

I'm curious about the lack of signal:

RE: Ghetto probe
I got the bypassed signal, with half the amount of buzzzzz.

Presumably this is connecting input direct to output to amp: That's good.

Toched at B, Half the amount of buzzz.

But was there any guitar? There should be, since it's just the other side of the input cap where the signal "enters" the transistor through the base. Either the cap is not connected properly, cap is defective, or the transistor is not powered or grounded correctly.

Measuring voltages at those 3 spots is the next step.

[madstayen]

@nocentelli: Guitar sounds through mixed with buzzzz when touching at A, and B, nothing at C.
Voltage at A=0.32V, B=0.71V, C=8.47V

@peterg: The out jack's orange and white goes to pcb ground. The in jack's blue and white goes to pcb ground. They both are connected on the sleeve lugs of the jacks. Thanks for naming the circuit, now I actually know what I'm building
Polarity is good, my Boss ME-70, and Boss HM-2 runs smooth on this. And my friends Micro Pog as-well.

[nocentelli]

It looks like you have a 390k instead of 390r (ohm) from emitter to ground.

pcb top

[madstayen]

OH MY BALLSACK..............You are right!!!!!!!!!!  Ooooops! Sorry for that. I have no 390r resistors or anything to divide to that. It's 01:30AM here in S.A, so I'll go to the shop tomorrow to get the right one's. Thanks for pointing that out. I will fix this tomorrow and keep you posted.

[peterg]

Nice catch, Leo   

[madstayen]

Well I swopped the 390k for 390r. Now I actually have sound coming through. Problem is, the buzzzz is still there

[Kipper4]

its a booster theres bound to be some buzz (noise).
Is it an acceptable level of buzz. Does it lessen with differant pick up?

[madstayen]

No, the buzzz is about the same level as the guitar. not much difference changing to other pickups. With the Les-Paul it screams like mad!!! Not good. I saw another schematic with R1=4M7, R2=430k, R4=43k. Will it help to change to that values? 

[duck_arse]

so both yr dr boogie and the booster are screaming with the les paul? both the same screeam?