OKKO Diablo + Voltage Doubler using switch

[teknoman2]

I would like to build okko diablo + and
I want to put a switch for selecting power supply, 9 volt or 18v.
I just saw max 1044 datasheet and I am bit confused.

http://www.stanford.edu/class/ee122/Parts_Info/datasheets/Max1017-ICL7660.pdf

The datasheet indicates that I have to use 2 10uf caps and Scottky diodes.
So far everything is normal.
I am going to use this schematic
http://www.box.com/s/qz7r3bgncl3jzgugoe3e

My main issue is  where am I going to put the double voltage circuit and the switch on the schematic?

[saxoftenest]

I drew a up a Diablo awhile ago (sans +):



Using my layout as a reference, you could also use the second column of a DPDT to bypass the 9V input of the charge pump.

[teknoman2]

Thank you very much, your schematic was very helpful.
I am planning to use it in mine.
Did you finally etched it and box it?
Are you satisfied with the results?

Also I would like to ask something about okko diablo +
In my schematic the boost circuit comes after the gain circuit.
Is that correct?
Usually the boost section comes first and then follows the od circuit.

[teknoman2]

I just finished my schematic without errors.

It's similar with yours.

Hope its ok for etching.

[saxoftenest]

I don't etch, so I had OSH Park fab up my PCB design of this schematic - sounds great! Here's a look:





Re: the boost section, it does come after the OD. I didn't include it because there are other boosters I like better and wanted to fit mine in a 1590B.

[teknoman2]

Nice one mate.
Really its a very good one.

Did you find any issues with the trimmers?

Were they easy to adjust them?

[cooder]

Oh man I would love a fabbed board like that for a small enclosure size!
Would you have any spare boards for sale, saxoftenest?
Cheers

[saxoftenest]

No extra boards, unfortunately. I have a few PCB designs that I may offer up for sale this summer of which this may be one...

[cooder]

I would be definitly keen for two boards of this and also interested what else you cook up...!
Do you have a website for orders or how to find out about it?
Cheers!

[juansolo]

Likewise I'd take a couple of boards if you did a small run. It's been on my list of things to do for ages.

[Tremster]

I'd take one of these Diablos as well!

[dc001013]

Id love to have a Diablo board also...

[teknoman2]

I just finished the schematic and the board section.

Probably by the end of the week I will send them to OSH Park.

If everything goes well I will make a dozen  of these boards also.

( I believe I have to change some drain resistors values to bias the J201 drain to 4.5v)

[Tremster]

Hello.
A humble inquiry about the state of the diablo.

[bordonbert]

Just to put this as a CAVEAT for anyone who comes across it at a later date...

The schematic shown for the Okko Diablo above is the standard web version.  There is also an accompanying schematic for the Okko Boost.  They are both wrong in a big way!  In all of the stages the capacitors between the gate and source of the upper JFETs are attached to the wrong end of their source resistor.  They should all be connected to the drain of their lower JFET.  You cannot get your Diablo working properly with the circuit based on that schematic.

This link will make it all clear for anyone who is interested.   http://www.madbeanpedals.com/forum/index.php?topic=17962.msg172734#msg172734  There is a link in that thread to a very good site where the circuit action is described in detail.