Fuzz Pedal Schematic Question

[aviherman5]

Hi, I had an inquiry about a schematic. Is the circled part right in the circuit? 


If it is not what should I do to fix it?

Also is this a good recreation of the above circuit?


Thank you!

[aviherman5]

My issue with the circled part of the schematic is that I think positive voltage and ground hitting each other would cause a short circuit.

[Axldeziak]

It's a battery. One end is positive, the other negative. There's a gap.

[aviherman5]

Hi, thanks for the reply, this better?

[11-90-an]

Hi, thanks for the reply, this better?

listen to idy below

also one leg of R2 isn't connected to VCC

My issue with the circled part of the schematic is that I think positive voltage and ground hitting each other would cause a short circuit.

the circuit you cited used something called "positive ground", which was used in the original PNP transistor fuzz face design. (but yours uses NPN transistors, so you did the right thing)

You have to remember that ground symbol is just a shortcut of writing. placing the ground symbol next to the battery basically means that all ground symbols connect to that.

p.s. there are some exemptions to the positive ground / negative ground topic, but others can explain it better than I can...

[idy]

You have converted a "positive ground" circuit for PNP transistors into "negative ground" and NPN. You also need to flip the polarity of the polarized capacitors.

[aviherman5]

Hi, thanks for the feedback. I'll fix that resistor ASAP. I'm actually using a PNP transistor so do I still need to change anything around or am I good? Thank you!

[11-90-an]

Hi, thanks for the feedback. I'll fix that resistor ASAP. I'm actually using a PNP transistor so do I still need to change anything around or am I good? Thank you!

You're using pnp... that would make it harder. flip the VCC and GND again, revert the caps to correct polarity. Basically copy the original schem you showed.

Are you intending to power it with a daisy-chain and with other pedals? or just battery alone?

[aviherman5]

So I fixed the resistor. Aren't the caps in the right polarity for PNP? Also, what do you mean by flipping VCC and ground? I attached my "final version" of the circuit here:



That good now? Thanks

[11-90-an]

So I fixed the resistor. Aren't the caps in the right polarity for PNP?

Yep. 

Also, what do you mean by flipping VCC and ground?

You connect the +9V from battery to "GND" and connect 0v from battery to "VCC"... don't really need to put it in schem, just keep it i mind.

Are you intending to power it with a daisy-chain and with other pedals? or just battery alone?

You need to answer this question. This would be the final factor of your PSU and other pedals getting blown and short-circuited or a nice and happy ending.

[aviherman5]

Thanks so much. Would you like me to switch the labels on these (the blue circle (9v and g in))? Wouldnt' that connect the sleeve of the cable to VCC?

[aviherman5]

Gonna be using a battery to btw

[aviherman5]

You connect the +9V from battery to "GND" and connect 0v from battery to "VCC"... don't really need to put it in schem, just keep it i mind.

this what you meant 

[duck_arse]

So I fixed the resistor. Aren't the caps in the right polarity for PNP? Also, what do you mean by flipping VCC and ground? I attached my "final version" of the circuit here:



That good now? Thanks

ground is ground. connect the battery plus to ground and you have positive ground, like for using PNP devices. connect instead battery negative to ground and you have 'positive supply', negative ground, like for PNP NPN transistors, when connected orthodox.

your circuit shows NPN transistors, which want positive supply, negative ground. and if "negative ground", you can't be pointing the "+" leg of capacitors at it, can you?

your caps are drawn correct for positive ground and PNP transistors.

youv've got to show your power source. as is, you have shorted the supply to the ground, doesn't matter which polarity.

[edit :] for polarity

[aviherman5]

So my power source would be a battery. So right now, with the circuit, you commented on can I connect +9v to "GND" and ground to "VCC" and it will work for a PNP transistor?

[duck_arse]

no. you can't connect ground to Vcc. Vcc is the collector supply, ground is the "other end". connect battery (-) to Vcc, and battery + to ground, leave the caps as drwan, use PNP, bob's yer uncle. bob's also your first shown diagram, the sun knob thing.