Ok, here's the pics of my DEM:
The Red arrow in both pictures points towards E2.
Hang on a minute, there's no R7 there! Does anyone know what it does?
I'm guessing changes the gain of the next stage?
These are the the connections to the board:
nb. The only "modifications" done were to run a ground wire from the E8
hole to the grounding tag bolted to the case, and replace the Vin Wire from the DC Jack. (I bought this as a faulty unit, and one of the power wires was broken).
I should probably have moved the red jack grounding wire from E5
to the ground tag too for proper star grounding, but didn't.E5
are board Gnd.E4, E7
are the board input, and are connected to the Switch (green wire), and Input/Direct jack (white wire)
The Yellow wire E6
is the board output.
Now, the wall wart conversion:
The main points are to remove D1 and the wires to E1, E2, and E3 from the transformer.
Your DC Jack should fit into the hole for the mains cable grommet.
No cuts to the board traces are necessary.
The 180 ohm resistor (1W or higher rated!) is connected to E1 and E3
The Zener diode connects between E2, and the stripe end of the old D2, it's oriented in the same direction as D1. This should be clear from the picture.
The V+ wire from your dc jack goes to the hole next to E2 where the other leg from the old D2 used to be.
The Ground wire from the DC Jack goes to either the chassis ground tag, 1/4" jacks, or whichever of E8 or E5 on the board is unused (depending on how much you care about grounding
The EH supplied wall wart is 24V,100mA CENTER POSITIVE!
and has 2.5mm plug. If you do anything different I'd strongly suggest labelling the jack.
Hopefully this is helpful to you.