probably done before they left China / Hong Kong . make it easier cheaper to ship .
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This arrived.
Itās that really cheap dual rail power supply kit from Sourcery. I ordered it a couple of weeks ago in a fit of āworth a shot at that ridiculously low price.ā
Edit: adding link to assembly video.
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Isnāt Sourcery Kristian BlĆ„solās (from MiaW fame) store ?
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Yes it isā¦
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Iām sure I read about it here in the power supplies choices thread. Kristian BlĆ„sol was mentioned. Iāll be watching this board with caution. Maybe itās too full of smoke for my needs, maybe not.
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Iām sure itās fine (Iād prefer some more protection diodes, but otherwise the schematics looks ok if a bit disorganized 
). IIRC from his videos, heās sourcing components from Elfa (Distrelec) and LCSC, so should be ok quality.
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Iāll compare it to the Frequency Central design and see if thereās anything I could add to make it better. For the moment, hereās a photograph of my kit.
The big electrolytic capacitors C5 and C6 are 4700uF 35V. C1 is 220uF 16V, and the other three (C2, C3 and C4) are 1uF 50V.
R1 is there to protect the LED from the 12V RMS AC from the wall wart. The resistor colour code reader app tells me itās 1Kohm but thatās what it said last time I tried it, on a different resistor.
There are three regulators: 7812, 7912 and (for +5V) 7805. There are three identical diodes: 1N4001.
You also get a quantity of male 2.54mm header, a barrel socket for the wall wart, and a 16-pin keyed box header for Eurorack. There is a space on the circuit board for an on-off switch but no switch is provided so Iāll make a wire bridge instead.
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The main difference to the FC will be that they use 3x4700UF per +/-12V which I presume just gives more stable output to the REGS.
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There is also plenty of room for heat sinks on the Frequency Central board. As @fredrik has mentioned, this Sourcery board is rather too congested for that. Since a linear regulator works by absorbing unwanted energy (and then dissipating it as heat) thatās a quite important difference.
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The regulators sit with their backsides to the edge of the board, so I would think you could mount heat sinks to them, hanging off the edges.
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Yeah, itās his smaller design that has one of them in the middle of the board. This one has the 7805/7812 on one side and the 7912 so while you need at least two heatsinks, you donāt need isolators.
(The 78xx has ground on the tab, the 79xx has the unregulated input there instead, so if you connect a 78xx tab to a 79xx tab, youāll short the transformer.)
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I canāt promise to get this soldered quickly. At the moment the situation is so unstable that I could plug in the soldering iron and get called away urgently before it gets warm enough. Iāll have fun playing with it alongside my Frequency Central board eventually, Iām sure.
Although these supplies nominally give you +5V as well as the +12V and -12V rail to rail Iām not sure that would be better than using the traditional 5V DC wall wart to power my Beaglebone Black/Bela board. For a start, Iām not sure theyāre up to supplying the kind of current these small computers draw.
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Okay, so as Iāve mentioned, that older gal who has been giving me stuff that she was going to discard otherwise gave me something today that I feel absolutely obligated to offer her some monies forā¦
It was just sitting in the bottom of one of the boxes she had me pick up todayā¦ 
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OK, we officially hate you now 
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Well, if you use this properly it will give you tons and tons of insight into electronics. Oh, yes and please refrain from connecting it to the mains power supply until after you have read the manual and have found out which probe you need to do that (if it makes sense at all, just a friendly warning) !
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at least with you it will be appreciated and get some use . we still hate / envy you
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I have the 1402 in my setup. Owned since new in 1997. Very solid and reliable with more features and tricks than it deserves.
Oh and due to pier pressure and the simple fact of jealousy I hate @d42kn355 too. 
(lucky bā¦d)
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Thatās some catch, that Catch-22.
I suppose thereās some overriding reason why the external tab in the 79 series isnāt ground, but it doesnāt seem like a very sensible design choice. I certainly see wisdom in Kristian BlĆ„solās board design now. Keep the carapaces far apart.
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Sorry, Iām too busy looking at the background location and the fact that youāre standing BEHIND the counter to realize youāve put an oscilloscope on the counter.
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