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    EEVblog #1056 – Digilent Open Scope MZ Review

    Dave looks at the Digilent Open Scope MZ Review, an $89 open source oscilloscope, logic ...

    • Jan Schmidt

      Thanks for the walkthrough of your design process for the calculator watch – it’s nice to see your logical progression laid out like that.

      I’m curious – what’s your definition of ‘cheap and easy’ manufacture for the PCBs and the front-panel PCB? What sort of prices? Do you have a particular place you get your PCBs made?

    • Roelf

      Loved this episode. Wish we had all the PCB facilities you guys have here in South Africa (our PCBs aren’t cheap, nor easy, nor as sophisticated). While we are on the topic, could we have some PCB software reviews.

      Oh, yeah, I’ve heard about the book before but never got around to buying one, so I forgot about it. Thanks for the reminder.

    • Eldon Brown


      Love the show, it is the first thing on my “to-do” list each AM – “check for EEVblog RSS”.

      I especially liked your calculator product design and thought process of episode #11. Keep up the good work!

    • Hi David.

      I just stumbled across your blog.

      I’ve watched the dodgy multimeter piece & your digital watch vlog.

      Fantastic stuff. You’ve got a great voice & distinctive inflection for delivering your story. Really enjoyable to watch.

      I’ve just discovered the Arduino (http://arduino.cc) and have been soldering a few jaycar kits together. I’ve got software experience & am loving the whole future of Open Software & Open Hardware.

      Do you plan on publishing your ideas & schematics for the cool things you make?

      I’m 35 and still remember calculator watches as being the coolest thing in the universe.

      Great work.


    • Another great episode. I read your build page for the watch a while back and thought it was pretty neat. I’m curious, though: you’ve gone with a PIC microcontroller. Any reason? A while back when I was first starting to mess about with uCs I looked at both PIC and AVR and decided that Atmel had the edge in a number of categories (per clock performance being the most notable). So why PIC?

      • Why PIC?
        The primary reason is that the project was done for the 2007 CircuitCellar PIC design contest, so it had to be a 24F series PIC!
        The PIC/AVR debate has been going since day dot. Atmel has the edge in speed and architecture if you compare the 8bit parts, but PIC blows Atmel out of the water in many areas like:
        diversity in feature set, seamless MASK-OTP-FLASH migration, unified development environment from 8bit to 32bit/DSP, and AVR doesn’t have a match for the PICkit2 programmer at the low end.
        The pro’s and con’s of each are many and varied and the arguments can be endless!

        • Szabi

          Hi Dave,
          Awesome tutorials!
          About the software part of your uWatch project,
          maaan I just get freaked out when I have to deal with such a complex design. Don’t know where to start, how to organize all the parts. I mean there are a lot of include files, tons of functions, hundreds of variables, the menu structure, so many things to keep track of. Aahhh.
          How you decide what goes into the main routine, and what should be left out, which part needs to have interrupt capability, all the timings and stuff.
          I am so confused.
          I guess you use some sort of a flowcode or something to help you keep track of everything.
          I am especially interested in the part, when you already have the hardware done, and you sit down and start to build up step by step the firmware.

          I definitely would love to see a blog about this. A long one. 🙂

          Keep up the great work!

    • Where do you manufacture the board?

      • http://www.pcbcart.com
        I’ll have to mention them in the blog soon.

        • jack

          Thanks for the info about your PCB manufacturer. I found their site a couple years ago, but never heard of anyone using them, so I used a different PBC company. I’ll give pcbcart a try.

    • ewertz

      I love the watch, but if it didn’t look as slick as it does, I probably wouldn’t. The attention to detail is truly what sets this apart.
      Have you considered putting this out as a kit? Kit design/distribution seems to be a geometrically growing enterprise here in the US.
      As an aside, if you were to do this, I’m positive you’d also find no shortage of fellow hackers with laser cutters (or 3D printers) that would do one-off re-skins over the PCB assembly, just for fun. I think you’d be surprised/terrified by what you see people doing with the kit if you put it out there.
      BIG thumbs up. Very nice work.


      PS: Wondering if you gave any thought to either capacitive or inductive touch with a stylus (like a glorified finishing nail, or something) to eliminate the buttons altogether?

    • Hi David,

      I found your blog a couple of weeks ago – I think it was via stumbleupon actually! I’ve been listening in ever since, and I now look forward to your updates. So keep them up!

      I felt compelled to comment on episode #11 because I particularly enjoy the “hobbyist” design chit-chat. I’m an Electronics Engineer myself by trade, and whilst I do find your equipment reviews very interesting (keep them going) I actually use most of the stuff you’ve mentioned – even the actual models – on a day to day basis so I have a good grounding in them already.
      Although I’m an Engineer by trade, I’m a hobbyist in my spare time and like yourself I also like to design my own stuff. So I was very interested indeed to check out your calculator watch. Our hobby is most probably considered the realm of the geek by most people, and I for one am not ashamed of that. I’d definitely wear a watch that I had designed myself like yours!!!! 🙂

      So yeah in summary, just keep up the good work! Nice one!

      Fellow Hobbyist,


    • Oh by the way, I forgot to mention:

      Someone else has commented that they’d like to see a PCB design package review. I think that’s a good idea. I swear by Eagle myself – it has a rather steep learning curve associated with it (as does any professional CAD program I guess) but once mastered it really is fantastic. Most people complain that the user interface is abnormal and uncomfortable to operate, and I’d agree that it adopts some rather quirky methods. But once you get used to it, the very same “quirky methods” you criticised when starting out, actually become EXTREMELY useful! I’d not be without them now!

      I’d be interested to see what design package you recommend.


    • Peter Kutas

      Hi David;
      I been enjoying your series of blogs, intersting topics…
      So when are you getting your watch project published in Silicon Chip??? Be great if you could sell it as a kit, I certainly would love to have one, just for the geek factor…

      Cheers & Keep up the good work…

      Peter Kutas

    • For those who have asked, the uWatch kit has been available for over a year now, but I am currently out of stock.

      Silicon Chip was offered the project but they turned it down.

    • tobias

      nice design ideas 🙂
      love your aussie slang – “no worries” !
      i’m looking forward to travel there next year.

      cheers mate !

    • Richard

      great work

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