How dya do it like that

[Kipper4]

First this classic

http://youtu.be/zVg2sL707gI

Question .I built Macs tres hombres
I'd like to incorporate a charge pump so I can use my normal centre negative power supply
So How dya do it like that
Schematic

http://www.aronnelson.com/gallery/main.php/v/mac/my+circuits/Tres+Hombres.GIF.html

I'd like to use the ic's I have 7660s
I'm not sure my caps are rated for 18v even.
So I was thinking can I do this and just use the +9v for gnd and 0v leave out the -9v
And still be able to use metal in output Jack and use my normal PSU.

I want my cake and eat it......

[digi2t]

Run your negative ground (normal power supply) into the charge pump, and the connect the charge pump output to your effect. Here's a layout, 7660 can be used as well;



Ignore the second +9 connection. Connect the power supply to the +9 and ground, and the effect to -9 and ground. See this doc, http://www.guitarpcb.com/pdf%20files/pumpd%20up%20fuzz%20face.pdf , and look at the schematic. It should clear things up for you.

And... be careful what you wish for.....

[Kipper4]

Thanks Deano
I've gone off cake now 
I'll probably parallel a 100nf from pin 2-4 too.

[duck_arse]

......... what? digi .......

[thermionix]

And......poop thread.

[Kipper4]

Okey dokey.
Voltage inverter installed. Thanks Dino.

Now I have another issue. A constant high pitched noise that I never noticed in past tests.
My guess is that it's RF noise on the input or interstage oscillation.

Note I haven't tried it with a battery yet or audio probed it to try to find its source.

So I'm looking for opinions on problem solving this issue.

Thanks

[Kipper4]

Its still there even powered by battery.
Intrestingly the middle transistor gives me a hum like a bad ground when i touch the case.

It must be probe o'clock.
laters

[Kipper4]

I soldered the transistors in the sockets.
Its still out of the box.
I put a shielded input wire in.
Probed it and its there from the first transistor collector and is amplified through the next two.
Still no joy.

[Groovenut]

Is the whine coming from the inverter chip? I personally use 100uF on the -9V output on my builds with a paralleled 100n MLCC.
Which chip are you using?
I use 7660SCPA or SCOA chips and haven't had any issues with whine thus far.

[Kipper4]

"Voltage inverter installed.

Now I have another issue. A constant high pitched noise that I never noticed in past tests."

Guess I should have listened to myself, there.....

That's calmed it enough to make it useable now thanks Law.
I had a 10uf in there.
I'm always surprised by how much power smoothing these ic's need.
I'm using scpa by the way.

[Groovenut]

"Voltage inverter installed.

Now I have another issue. A constant high pitched noise that I never noticed in past tests."

Guess I should have listened to myself, there.....

That's calmed it enough to make it useable now thanks Law.
I had a 10uf in there.
I'm always surprised by how much power smoothing these ic's need.
I'm using scpa by the way.

You can get away with much less filtering with opamps than you can with discrete transistors and fets. I have been able to use a 1uF filter on the -9V output with opamps without audible artifacts (depends on the opamp and circuit). Discretes don't have the active power supply ripple rejection (PSRR) that opamps do so you have to filter the ripple more. It's good design etiquette for opamps too, but if space is at a premium it's good to know you can use less.

[Kipper4]

Thanks Law
Always good to know, it makes sense.

[mac]

Rich,
Glad you like it.

Is it PNP Positive Ground?
Did you try PNP Negative Ground?

mac

[Kipper4]

Its PNP positive ground Mac.
turns out it was my tiny amp that was part of the problem too, once i tried it on the bigger boy its fabulous.
Cheers Mac

[mac]

Just curious, what transistors did you use?

mac

[Kipper4]

Ac153