UCload: revisited


Sjaak has posted an update on his uC controlled dummy load project we covered previously:

I finally found some time to check out the UCload project. A couple of weeks ago I quickly soldered the PCB and wrote a quick’n’dirty firmware for it. The basic functionality was working, but it wouldn’t do good for the shiny display.
Today I locked myself in my mancave and shut myself off from the world. Turned the light down, pulled loud music from the speakers and started coding like hell!! Not exactly but I found some time to write some more decent firmware for this load. In a previous revision of the PCB I forget the pull up resistors and swapped the SDA and SCL signals. I corrected that and made some small other changes (still ****ed up the silkscreen) in revision 2. The hardware is quite OK and rock solid (prolly more due to the robust FET then my analogue skills :)). However I managed to use a 1n4148 diode to measure the temperature. Connect it to the heat sink and if that one gets to hot turn on a fan. It accuracy is terrible but capable of detecting over temperature :)

More details at smdprutser.nl project page.

Via the project log forum.

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  1. It would have been helpful to mention that the project is not in the least open in any sense, so those actually interested in the device (or sharing) may stay well away from it.

    1. It isn’t yet open as it is a Work in Progress. I will open things up when they are finished (enough) and the code is cleaned up.

      If interested how the thing works please read the forum post as it directs you to the basics of this circuit.

    2. I believe projects can be shared in any form whatsoever, even if it’s a single photo and nothing else. There should be no expectation of open hardware, no expectation that any electronics hobbyist somehow has a duty to do things for other hobbyists.

      Let us share however we want to share, without any rules foisted upon us.

      1. And I believe that closed projects are not worth wasting my time (and of those with similar interests) which is why I suggested mentioning that this is not (yet) the case here would have been helpful. Obviously, that implies no expected restriction on who may share what. As to what my expectations may or may not be that is for me and me alone to say.

        @Sjaak: good to hear it is intended to end up being opened; I’m familiar with the arachnid labs circuit, thank you; I do intend to replicate the original non-digital version of it at some point, which is why this version piqued my interest.

      2. I respectfully disagree, I think if DP blogs a project that is from another site, DP has no duty to specify whether the project is open hardware or otherwise. Readers can discover it themselves, after all, someone has made an effort to put something online, let’s not be stingy, we should go and browse the original page if we want to find out more. Isn’t that the whole point of mentioning these projects? If you have the time to comment on this blog, shirley you have the time to browse the original page…

  2. I don’t care how fancy it looks, or how much smarts it has. 99% of these dummy load projects all have the same basic flaw: reacting very poorly to PWM driven outputs.

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