18V Electric Mistress: pcb

[psst]

Christmas present.   

Taken directly from a '79 original, I built it and sounds really cool.

Enjoy.

[John Lyons]

Cool, thanks!

jOHN

[Barcode80]

scaling?

[John Lyons]

I just use photoshop and a piece of perf as a Template...There are many threads here about scaling though...
John

[$uperpuma]

yeah, size it till a dip socket lines up then you're there...

[rockgardenlove]

Christmas present.   

Taken directly from a '79 original, I built it and sounds really cool.

Enjoy.

Pics don't work for me...

[psst]

More info:
This circuit works at 13V (although EH gives a valid 12-13.5V range). But this is an old design, and the part of the circuit that gets 13V out of the 18V supplied by the  two batteries is quite unreliable and probed to fail. So Electro-Harmonix supplied a document with some changes in the power section in order to do it more reliable.
Here are the changes:
- Replace the 2N5087 o BC309 for a 2N4354
- Replace the 2N3563 at pin 2 of the 741 for a zener diode (6V8)
- Replace the transistor or zener at pin 6 of the 741 for a 47k resistor
- Replace the 18k resistor at pin 3 of the 741 for a 22k

I found a schematic on the internet, and traced my original '79 18V Electric Mistress and put the corrections in the schematic (in red). Not important things, just a couple of values, the only "important" thing is the little error in the schematic (there's a "dot" left, I put it in red).
Also, I wrote in green color the power section modifications.

[Seljer]

isn't that layout missing the trimpot thats providing the bias voltage for the 4558 (in the bottom left of the schematic)?

[psst]

Actually. missing BOTH trimpots.
In the original the two trimpots are soldered to the other side of the pcb, so you have access to them just opening the case.
In my clone I soldered to the components side, I'll draw them, but it's pretty easy to see where they are looking at the schematic.

[psst]

Ok, I put "*" where the trimpots go (I know, I know, but I'm lazy  )
One is in the right side (parallel to the 7k5 resistor), the one that sets the "Color" pot limit so it doesn't scream (if you don't want that, of course). That's wired as a variable resistor.
The other one is in the left side, top. The tip goes to the lower "*".

[mudmen]

I know you're lazy but are there any chances for offboard wiring (with true bypass if possible) 

[boogietube]

Am I wrong or isn't this available at GGG?

[Seljer]

Am I wrong or isn't this available at GGG?

I believe this one is the very first one, that came in a Big Muff type box and only available for a couple of years until they redesigned it into the Deluxe Electric Mistress (the one on GGG) , in the enclosure that we still see them in today with the knobs on the right side and powered directly from the wall (and they eventaully made a 9v version too)

[Meanderthal]

 Yep, like the one ELO used on the fade in for "Turn To Stone". Well, and about a thousand other songs.

[John Lyons]

psst

Did you use a an 18vdc supply or did you make a power board inside your unit?
I'm  just wondering if I can use an 18v walwart supply I have or if I need to go from the ground up with the raw transformer and specific filtering and doides in the box on a power board.

Thoughts?

Thanks

John

[Meanderthal]

 There's always this:

http://www.diystompboxes.com/pedals/vdbl.html

Although the voltage only gets stepped down later anyway. I'm pretty sure someone recently posted a version that stepped it up from 9 to 13v also...

[psst]

Yeah, there are three versions:

- The first one is this (18V, non deluxe):



- Then the 9V version, that has the same box

- And then, the Deluxe version, that's the one that is inn GGG:



John, I use my own power supplies, they are inside a big box with all my "Pink Floyd" pedals:

[Auke Haarsma]

nice gear man!

[bettsaj]

This is an old post..... But is there a copy of this PCB out there? There is a layout on GGG for the Deluxe Mistress, but i want to build the Original 18v Mistress.... Can anyone help??

[bluebunny]

Madbean's "Current Lover" is a 9V adaptation, although Brian says it runs on 12V too.  Check out his Projects page for a PCB.