Using a max1044 in PNP pedals

[skrunk]

I'm looking at building a PNP Ge fuzz face with a max1044 chip to convert the voltage.
I'm going by RG's diagram here:

http://www.geofex.com/circuits/voltpmp2.gif

I'm just a bit confused as to how it connects to a PNP circuit.
presumably the -9v (pin 5) goes to the -9v of the FF circuit.
but what connects to the +9v of the FF and what is ground? this is where I get confuddled.
if +9v from the chip (pin 8) connects to +9v ground of the FF, what is pin 3 grounded to?
I feel I'm missing something really obvious. :icon_redface:

ok, found this which helps a bit:
http://www.tonepad.com/getFile.asp?id=118

but I'm still confused about the difference between ground and +9v from the chip.
is say, the ground that the FF's Q1 emitter connected to, the same as the ground connected to pin3 of the chip?

so if I understand the tonepad diagram, the +9v of the chip is ignored, and the -9v powers the effect?

[caspercody]

From reading the description of Tonepads bipolar power supply, you are correct that the -9volts is used for power and the +9volts is ignored. The ground is the same point on the power supply and the project.

[skrunk]

thanks, yeah that what I get from it too.
I have it like that on the breadboard right now but its not happening for me.

I get -4.7v at pin5, which I've connected to the -9v rail of the effect, but I'm getting 0v at that rail.
all that's connected to that rail is the 490R and 33k of the fuzz face.

[R.G.]

Yep, CC is right.

The whole point is to take an existing +9V, which can be used for other pedals, and ground, which goes to other pedals also, and make from these a -9V which can power a Fuzz Face or other PNP positive ground pedal without the power/ground interaction you'd otherwise get.

The whole thing will make more sense if you draw in some other blobs which represent other pedals, and take +9V and ground over to them. Then ground and the new -9V go to your fuzz face. Everybody gets to use the same ground and play nice together.

[R.G.]

I get -4.7v at pin5, which I've connected to the -9v rail of the effect, but I'm getting 0v at that rail.
all that's connected to that rail is the 490R and 33k of the fuzz face.

You have a connection or hookup bug.

[skrunk]

heh the chip wasn't sitting in the breadboard fully
works a treat now, thanks guys!
this is really useful.

[R.G.]

heh the chip wasn't sitting in the breadboard fully

My favorite trick to play on myself is to socket ICs in a board, then do my debugging from the bottom/trace side and not notice I didn't put ICs in the sockets.