Tuesday 3 January 2017

Getting seriously pissed off with SMPSU suppliers!

 After the 24v 3A SMPSU from China that blew up, I decided instead to obtain one from a UK supplier, in this case trading under the name 'Makershut',

Well, it was over twice the originals price, and on arrival this morning (give them credit it was sent quickly and well packed), two problems were immediately apparent. First, its twice the damn physical size! Ok, I can probably live with that,

What I cannot and will not accept however, is any electrical safety issues. And this has them. A cursory look through the ventilation holes revealed A) one of the transistors tabs that should be secured to the heatsinking of the case is not. Its bracket is present but not positioned. And B) there are numerous blobs of solder on the silkscreen/component side of the PCB. Just one of these coming loose could not only short and destroy the unit, but could cause a fire.

The photos below are not the sharpest, but they do show the faults. The reason for them not being SLR quality is that in order not to have to break the warranty seals, these were taken using an endoscope.


Solder spall by capacitor CY3 (potentially a class Y capacitor)

Very poor fixing bracket
Solder spall by C19


Transistor tab not even close to chassis!


No. Im not at all happy.

I have started the return process. I expect to receive a full refund including the shipping.

Edit - I have received a prepaid return label so this will be going back. 
As these units do not have a serial number. I have taken the liberty of adding an identifying mark to it in such a way as to be able to identify the module as being the one I sent back. I have photographed the mark but will not post the photo for obvious reasons! 

On a slightly lighter note, thanks to help on the Arduino forums (I will give full credit if these chaps agree) I now have some better understanding of how to read the frequency dials of the RT-320, including some clever use of arrays to make the code more compact. Im now trying to get my head around the section of the code that actually reads the dials and returns their values. It is these returned values that I will have to manipulate to obtain the equivalent dial settings.

This section of code initially wouldnt compile. A bit of head scratching and a few trial changes, and I managed to actually debug it! It seems a command for reading the pins was written incorrectly. Its now doing as expected - reading all the pins, in their appropriate 'dial' groups, and returning the expected value for each of 255. This being as they are all pulled up to Vcc as I havent yet actually connected any switches!

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