Hello Dave,
My Korad KA3005P PSU I ordered through Amazon have just arrived. At first I stumbled upon a pretty ugly production mistake: the positive and negative power posts had the colours swapped! Apart from that everything ok, at least from an initial inspection. Mine has a switch in the back to toggle between 115V and 230V input. Had to change to 230 V because I live in Europe (the PSU was bought from the american supplier SRA Soldering Products.
Anyway I coudn't resist opening the unit to fix this minor issue. Upon opening it I found that it has the new regulator circuit board (supposedly dealing better with heavy loads than the one you tested). The board had one difference however: instead of the large 6800 uF capacitor it has three smaller 2200 uF caps.
Another detail of this model, is that instead of the M5 led it has a led labelled as LOCK, and is set when we press the corresponding button (to of course lock the keypad). A very good improvement
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
I haven't done any torture tests yet, only a few basic tests. I notice that the fan reacts quite dinamically to the load changes (supposedly varying the rpm based on the temperature). It vibrates somewhat, even after providing extra torque to the fixation screws.
Regarding the PC interface, I could not install the CDC driver in my Windows XP. Apparently the .INF file is not correctly written. I then tried booting in Ubuntu linux, and it was pretty straight forward. After turning on the power supply linux recognizes it as being a generic usb cdc device, creating a device under /dev/ttyACM0. Through minicom I managed to issue the commands described in the manual contained in the cd-rom. It supports SCPI style queries such as *IDN? As the Windows drivers could not be installed, I could not test the program included in the CD-ROM. However, as the commands are documented, it is a pretty straightforward task to write a similar application in Java or even C/C++.
I tried to measure the ripple, but could not distinguish it from the 12 mVpp of noise at the probe, even with the PSU turned off completely.
Overall, assuming no more issues are present in this version of the PSU, this is a pretty nice buy for the price. Most other products in the same price range aren't nearly as interesting as this one. I would say this is the Rigol DS1052E of the PSU's
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
Another interesting fact is that this matches the Velleman equivalent:
http://www.velleman.eu/products/view/?country=fr&lang=fr&id=409798which is pretty much the same power supply.
Best regards,
Luis