Wow 3 Washingtonians!
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Here’s mine so far. I built a simple mult and converted an AI Synthesis mixer kit into Kosmo format. I’m probably going to need another case soon.
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nice ! yes the more we advance the more we want to build other modules so more cases 
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Looks nice . my approach was to build the wall of boxes to fill [ carpenter] not sure if that was a good idea $$$$…
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Hi all! I was asked to post this here : )
It’s a Doepfer 6U case, which I converted this afternoon to accept Kosmo modules : )
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Thanks for showing this in the forum!! Hope you enjoy it here 
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Many thanks! Could be useful ; D
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hi and welcome to you, nice work (the only flaw in my opinion is just that it will take a lot of box like this one for the following ).
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The layout reminds me of the nuclear pack the ghostbusters wore.
Doepfer goes for good old fashioned power supplies, no smps, no HF noise. Neat !
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That’s the old A-100PSU2. The new A-100PSU3 uses a couple of beefy 15 V switch mode converters before a linear stage.
(the “miniature” supplies on that page intrigue me – seems they were once selling a wall wart style supply for use with “about 9 V AC” in, but judging from the PCB layout in the manual it’s a straightforward 7812/7912 circuit, so how do they get from (9−0.7)×1.41=11.7 V to a stable 12 V with a 7812? Later versions require 12-15 V AC which makes more sense, but looks like all they did was to remove a couple of caps…)
EDIT: Oh, wait, there’s a couple of diodes *after* the first capacitor pair. Did they use a voltage multiplier? Sneaky.
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Thanks! Yeah, but a couple of them will look cool : )
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It’s actually 9x1,41 - 0,7 = 12,03V
It’s still theoretically not enough even with a low dropout regulator, (maybe they used schottky diodes?) but my guess is they relied on the fact that transformers actually put out more that their rated voltage, especially when lightly loaded, rather than having a voltage doubler (which would bring the voltage too high for nothing and waste power).
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Well, d’oh! 
But on the other hand the 1N4001 has a higher forward voltage so with 9×1.41-1.0=11.69 we’re back where we started 
But would they be crazy enough to design with a 20-25% no-load factor? And then tell people that they can use any wall wart that produces “about 9 V AC”. And not just “about 9 V” that I got from the PDF manual linked from that page; it turns out the HTML manual says “If you want to use another power supply instead of the one supplied, it must have a voltage output of about 7 to 9 V AC and a capacity of at least 300 mA.”
After a bit more googling for actual schematics, I found a MuffWiggler thread from 2013, where someone suspected a half-wave doubler:
https://www.muffwiggler.com/forum/viewtopic.php?t=89440
which indeed matches all the published data.
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I ran a simulation at falstad.com of the circuit described in that muffwiggler thread (with 2.2µF capacitors as shown in the Doepfer documentation) and it works better than I expected, but even with a 9VAC RMS wall wart, you need a wall wart capable of peak currents of a bit over 2A to maintain high enough output voltages with 200mA loads.
(I simulated the loads with 200mA current sources and added a small resistor to the AC voltage source to limit the peak current out of the wall wart model).
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wow!! thats maddddddddd I thought you somehow made is smaller thats awesome
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Cheers! : D No, I didn’t need to fiddle with the outside of the case, it’s 31 cm wide, so there’s a bit of extra room.
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as it seems for now …
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