Simple Booster

[madstayen]

Look at this schematic I found somewhere (really can't remember)
Well I added the pcb lay-out, and would like to know if it is correct, before I continue with this little project. Any help welcome. Thanks guys

[nocentelli]

Pinout is reversed if you're going to use 2N5088/9, just flip it 180 degrees. You also might want to put a large electrolytic cap across the power supply (with or without a small series resistor) for a bit of power filtering. Other than that, looks fine - Nice work!

[drolo]

Provided the orientation of your transistor is correct, you should be good to go ;-)
if you use a 5088 like in the schem, it's reversed.

[waltk]

Look at this schematic I found somewhere (really can't remember)

Looks very much like a Dano schematic (beavisaudio.com).

[madstayen]

Makes sense, I will swop it around thanks. And can I use a 100uf+ cap and a 1k8 resistor? In series of-course.

[Pojo]

100uf is fine, common values are in the 10uf - 100uf range. I usually go with 100ohm for the series resistor. Don't put the cap in series, it goes across the supply with positive cap lead going to +9v and the negative to ground.

Good job on the layout!

[madstayen]

Thanks, I'm a quick learner, plus, I'm getting advice from genuine experts, so I can't go wrong. Yes, I understand that the cap should be grounded, I was actually asking if I should place the resistor just after the cap, but it makes sense that it should be, so never-mind that. Thanks for the advice, will go and change it quickly.

[madstayen]

All I'm getting is a buzzing sound, with, or without the guitar plugged in. No sound of the guitar comes through.

[nocentelli]

First off, the supply needs to go like this:

+9v ->100r resistor -> 100uF positive (negative to ground) -> R2||R3

If you have followed the layout you've posted exactly, with transistor orientation correct and roughly 9 volts at the supply side of R2 and R3, I'd probably try an audio probe next to see if signal is reaching the base. If that proves to be the case, measuring transistor voltages would be the next step.

[Hemmel]

I don't get the "9V + IN" and "9V + OUT" connections.
All's ok if you put the battery + on "9V + IN" but I hope you're not connecting ground to "9V + OUT" ??

[madstayen]

So here's the update then:

[madstayen]

The 9V out is for connecting a 3pdt switch. Yes, my psu + is connected to the 9V+ in.

[nocentelli]

Why would you connect +9v to the foot switch? For the LED?

[Hemmel]

After applying the changes, do you still get the buzzing sound ? Still no guitar sound ?

[madstayen]

Yes the V+ Out is for an LED, Aron's method. Yes, I still get that buzzing sound, even if I unplug the guitar, only difference then it's much worse.

[Hemmel]

Can you take a picture (or more than 1 if you can) of what you made ?
I'd like to see those connections (board, connectors and switch).

[madstayen]

Yes I will, just give a minute or so, no problem. I didn't wire the switch in yet, just the basics to check the functionality of the board (input jack tip to board, input jack sleeve to ground, output jack tip to board, output jack sleeve to ground, and dc psu ground lug to board ground, dc psu + to board) Photos coming up in a minute

[nocentelli]

Rig up a ghetto audio probe, and turn your amp down a bit: Temporarily solder a length of wire to your output jack connection - Touch the other end to the input jack and you should get the bypassed sound. Move it to the transistor side of the input cap (i.e. the transistor base) and you should still have sound. Touch it to the collector, and it should be LOUD. Where the signal disappears will pinpoint your problem.

[madstayen]

How do I do that(ghetto audio probe)?

Transistor
Cap and resistor mod. I couldn't place the cap and res after the diode without making a new pcb, but it shouldn't matter.
pcb top
DC jack
Input jack
Output jack
Pot
Setup

[nocentelli]

Temporarily solder a length of wire to your output jack connection - Touch the other end to the input jack and you should get the bypassed sound. Move it to the transistor side of the input cap (i.e. the transistor base) and you should still have sound. Touch it to the collector, and it should be LOUD. Where the signal disappears will pinpoint your problem.

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