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Member Since: August 19, 2011

Country: United States

  • The AtMega CPU's can be used in very low-power applications. The Sparkfun BigTime watch kit is a great example. I built these with my kids, and they are still "ticking" on the original CR2032 after more than 3 years. Take a look at the clocking options in Atmel's full datasheet for the AVR. There are many. You can have a 32kHz external oscillator (as does the BigTime kit), and still have access to multi-MHz clock frequencies on a dynamic basis as processing needs demand.

    The various Arduino platforms that use AVR's are not so optimized. It would be nice to have a Pro Mini sku with a 32kHz crystal, for instance :-)

    BTW, kudos to Sparkfun for adding the power isolation solder bridge, which can remove the LDO regulator and the LED from the circuit if they are not wanted/needed in the application. The previous version of the Pro Mini did not have this. I didn't notice the change until just now.

  • I have had 5 LED bulbs fail: 1) A Home Depot "ecosmart" brand 40W bulb made by Lighting Science that was later recalled. It simply quit working. The recall said that it might catch fire, so I guess I was lucky.

    2) A Cree 100Watt ($20!) bulb from HD that is not rated for use in an enclosed fixture, but I had installed it in one anyway. Quit working completely, slight burnt smell.

    3) Two Cree 60 Watt bulbs from HD that are allowed in enclosed fixtures, and were installed in enclosed fixtures. These started flickering horribly. When I took them out of the fixture, they had a nice "burnt" smell. I'm torn as to whether I should disassemble, as they should be replaced under warranty if I refrain from taking them apart.

    4) Another Cree 60 Watt bulb from HD, not in an enclosed fixture, flickering more than is tolerable, no burnt smell. HD exchanged this one.

    I've always had trouble with lights burning out early, whether they be incandescent, CFL, or now LED. My line voltage is at the high end of the allowed range: 124-125V. It's reasonable that this would shorten the life of incandescent bulbs rated at 120V, but it shouldn't affect CFL's or LED's with switching power supplies.

  • Second that...

    I would love to see Sparkfun make an arduino.cc-licensed "Redboard Zero" and/or a "Pro Zero" (might need a different name for the latter, though.)

  • There are "grid interactive" systems that are grid-tied, but also incorporate batteries. I think these are typically installed to provide emergency power when the grid goes down, rather than to manage peak loads.

    With that said, it would be interesting to see how the "billable demand" aspect of commercial electrical service affects the economics of grid-interactive PV.

  • A few IoT-related Q's:

    1) "Always-on" LED's burn precious joules... The pro's and pro mini's still have them. (I'm listening to the last question now... the pro and pro mini are way better for low power than the Uno, but the LED still blows the power budget!) Yes, I can de-solder the LED or its series resistor, but I think the pro series would be better off without the always-on LED. I don't mind the IO-controlled LED (so the blink sketch can still work).

    2) Any prospects for additional cellular modems besides the sm5100? GPRS GSM meets the needs of almost every IoT project requiring cellular communication, but the 2G network's days may be limited, at least in the US. I'd like to see a 3G cellular modem that is serial-controlled (not USB or PCI express), low power, and not too pricey :-)


  • Coil voltage might be nice to know too... If the photo is correct, then this is a 12-volt DC coil.

  • Does anyone know the length of this sensor? The manufacturer makes a number of different lengths (up to 1 meter), but I don't see which length is being sold here.
    The datasheet and dimension drawings do not indicate a length either.

No public wish lists :(