Hackaday Links: December 11, 2016

We have a contest going on right now challenging you to do the most with 1 kB of data. If you want to get into this, here’s how you do it for a dollar. Use the PIC12C508A. It’s an 8-pin DIP, has 768 bytes of program ROM and 25 bytes of data RAM. [Shaos] is trying to generate NTSC on this thing.

Remember that Internet of Cookie Oven Kickstarter from the links post a few weeks ago? It was funded. It has a heating element that is ‘more energy efficient than traditional electric elements’, and there’s still no consensus over how a resistive heating element can be more efficient. It’s either 100% efficient, or 0% efficient, depending on how you look at it.

[Matthias Wandell], master of wood gears recently built a 20″ bandsaw from scratch. It’s a wood frame, wood wheels, a (currently) underpowered motor, and a few bits of metal and rubber. The video build log is fantastic, so start here and work your way forward.

Way back in the day, Sparkfun sold a Bluetooth rotary phone. Yes, at some point in the past, phones didn’t have touchscreens or even buttons. In any event, Sparkfun hasn’t sold these phones for quite a long time. Now there’s a new hotness: giving these rotary phones a GSM module.

Here’s a little Hackaday Events housekeeping. On January 23rd, we’re going to have a meetup in NYC. We’ll also have a meetup in LA sometime in January as well. Also in January I’ll be attending CES, reporting on the latest Internet of Toasters. A week later, Hackaday will be at ShmooCon in Washington, DC. At ShmooCon last year, we had a breakfast meetup in the DC Hilton. This year, I want to do something similar. If you have an idea of what to do, leave a note in the comments.

31 thoughts on “Hackaday Links: December 11, 2016

  1. I think the point (if I’m reading right) is that the heater in the CHiP Smart is 1300W while a traditional electric oven is 2500-5000W. If it really does need no preheat time, then it would use less overall electricity than pre-heating an oven and then cooking. I have a thing about unitaskers and I probably don’t need cookies that badly so I’ll pass on this.

  2. A heating element can’t be 100% or 0% efficient. Either % would indicate infinite resistance or an open circuit. Some electrons have to flow on through to have a working circuit.

    It’s not possible to convert 100% of the electricity going through a heating element to heat or heat and light. Visible light in a heating element (as in an oven or stovetop) is wasted energy for the purpose of cooking.

    A more efficient electric heating element will convert more electricity to heat (infrared) and less to the visible spectrum.

  3. Ohhh, wow, carbon-fiber cooking elements!
    “Delay Start Mode allows you to start baking anytime within 4 hours of setting the dough into CHiP. Put the cookies in during your lunch break, before a workout or for a nice afternoon snack.”
    Yay, start cooking food while nobody’s home! That sounds completely safe and I get cookies! And it is so smol too! I’ll bet it fits right under the cupboard where I keep the cooking oils, sugar, and flour! So efficient too!111!!

    1. I still don’t trust them. Wouldn’t set an automatic cooker even if it meant Christmas dinner would be late.
      I know too many people who have had their homes burn down. :(
      Sorry for so much sarcasm above, but it struck a nerve.

      1. Me either infact, the other week my girlfriend turned the grill on instead of the oven, closed the kitchen door and left the food to cook. going back into the kitchen the rooms was filled with smoke from the rubber seals on the grill getting too hot and smoking. dinner was ruined, Seals were done, kitchen stunk off burnt rubber for a week but luckily no one was hurt. a simple lapse in judgement can kill you now if you make a similar mistake with a remote controlled cooker you may lose your home.

        1. I’ve never seen a kitchen that can be shut off with a door. I have seen short louvered double hinged doors but nothing that would shut off smoke. It would probably better at delaying any knowledge of a fire than containing a fire itself. Sound like a safety failure.

        2. @RÖB You are right it didn’t shut the smoke off but it did stop us noticing until the rooms was filled, Nothing caught fire just the rubber gaskets were smoking heavily because of the heat. We were in another part of the house at the time. I think I will add a smoke alarm just outside the kitchen area so if it happens again it is caught much earlier.

        3. It’s better to put the alarm in the kitchen and perhaps another outside. Hot gasses like smoke lift and fill from the ceiling down so it will have to fill the top 60 – 75cm down from the ceiling before it can get across the top of the doorway to the other alarm and that will waste valuable time.

  4. NTSC on a PIC12C508A is going to be a huge challenge as they have 4 clock cycles to 1 machine cycle. Fortunately all but things like jumps instructions are 1 machine cycle to 1 instruction cycle. But that still leaves you with a quarter of the MIPS and a quarter of the pin toggle speed of something like a AVR.

      1. Here we have about 64us per line (PAL) and doing a line in 64 instruction would be next to impossible for any decent resolution. Probably 30 odd pixies horizontally. Reminds me of a retro computer that I think was called a Dream 6800.

        Out of curiosity I looked up the PIC12C508A datasheet but it didn’t give the information I needed to extrapolate a maximum Fosc @ an average room temp and Vcc = 5V.

        For example you can overclock a 20MHz ATmega up to 32MHz if you run it at room temp and Vcc = 5V. It can’t do this using the internal crystal oscillator circuitry as it fails at a lower Fosc but if you use an external *active* crystal oscillator then the chip will work fine at the higher clock of 32MHz and possibly higher.

        Anyway the reason I was curious was that pushing Fosc up to twice the color sub-carrier may have advantages with color if you want to test it further later on, it helps if all you code is designed to run at a multiple of the sub-carrier from the start.

        While I have the datasheet open, An external *active* crystal oscillator would connect to pin 2 so it looks like that would free up pin 3 for something else.

  5. I like that “ultraviolently-erasable” [sic] PIC. Do you erase it with a hammer? ;) Actually, I appreciate the challenge of NTSC on a cheap device, but realistically the ESP8266 does not cost a whole lot more and has a lot more to offer.

    1. My cat put his paw in my UV eraser and now he only has three legs!

      I had never seen such a small (DIP-8) UV erasable chip before. It looks cute. It’s a shame that there aren’t many left now because of ultraviolent erasers.

  6. People normally care about billable input energy and useful output energy. Considering these two quantities, efficiencies (=out/in) are NOT bound by 100%. A simple example is a heat pump, which uses your billable energy to *move* warmth from outside of your home to the inside of your home (technically making it colder outside). It’s common for heat pumps to exceed 100% efficiency… they use non-billable energy to help accomplish their task, so that non-billable energy appears in the output (increase in thermal energy of your home) but not in the input. I often say electric heat is intrinsically 100% efficient, but that’s only half of the story. It is pedantic and unuseful to say that an electric boiler is 100% efficient if it’s unintentionally heating your basement as well.

    Specifically regarding electric oven heating elements (as opposed to the whole oven design), the “useful output energy” is not simply all of the energy emitted by the heater… it’s only the energy absorbed by the food. A traditional resistive heater has to warm itself, too. Since you don’t let them cool before removing the food from the oven, all thermal energy left in the element itself is wasted. A small heater with a low heat capacity (see Wikipedia: “heat capacity”) will hold less energy after cooking than a large heater or one with a high heat capacity.

    100% efficient cooking would mean no preheating and no removal of the food while the oven is still hot. The most efficient *reasonable* oven would heat up and cool down very easily, so there wouldn’t be much energy left after the food is removed. It would probably be as small as possible and very well-insulated.

    Another poster wrote, “If I can see it’s hot that is not useful heat.”, but this is not true because temperature increases upon absorption of the light. Electromagnetic radiation is a form of thermal energy transfer (along with conduction and convection). Nothing makes infrared intrinsically special.

    It’s interesting to note that microwave ovens start at room temperature and (for short cooking times) end at nearly room temperature, and don’t feel hot from the outside. They may be the most efficient way of cooking food.

    1. A microwave oven is definitely NOT cold on the inside. If you gut one, you’ll see that the magnetron has nice cooling fins and a fan blowing air over them, and let me tell you – it does get hot!

      It’s still a vacuum tube that needs about 30W to heat the cathode in order to make the pixes leave it (and take the heat with them. Then, when said pixies are done dancing around in magnetic fields and producing microwaves, they smash their faces into the anode and it gets hot.
      Also, whenever the waveguide coupling or absorption by the food isn’t perfect, a portion of the radiated output is reflected back into the magnetron, further heating it.
      Last but not least, there’s the brutally undersized transformer, which is probably responsible for most of the losses.

      1. Ah, good point. I still wonder how a microwave oven compares to a traditional oven regarding overall efficiency. The magnetron has a lot less thermal mass, even after accounting for the smaller relative size of most microwave ovens.

  7. I wonder if a modern person could get used to rotary dial phones. I mean if they for some reason had to. I think the modern psyche isn’t up on the frustration myself.
    I know I find them quite insufferable, the long wait for the thing to return to default position for the next number.. damn it’s almost impossible to stand.

  8. Absolutely do not consider my comment an endorsement for the kickstarter oven!

    “It has a heating element that is ‘more energy efficient than traditional electric elements’, and there’s still no consensus over how a resistive heating element can be more efficient. It’s either 100% efficient, or 0% efficient, depending on how you look at it.”

    This is a common misconception and is rooted in thinking inside the box: closed systems. Theres also open systems in contact with a heat bath (for example ambient room temperature, or the atmosphere or …). You could convert the electrical energy directly into heat, but one can also use the electrical energy to pump heat from a heat bath (which by definition ideally stays at the same temperature even though you perform work to extract heat from it) into a target system.

    According to wikipedia “Heatpumps in general have a COP of 4.2 to 4.6” so that means for every joule of energy applied to the pump, it will be able to pump about 4 joules of energy from the heat bath to the target system. Of course the COP will depend on the technology used and the source and sink temperatures.

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