bobski

Member Since: February 25, 2010

Country: United States

  • Product SEN-09403 | about 4 days ago

    Pellet guns use tanks of CO2 (carbon dioxide), not CO (carbon monoxide). Attempting to calibrate this sensor with CO2 will likely result in badly skewed results, if the sensor responds at all.

  • News - Enginursday: Yeah, I foun… | about 2 months ago

    Same thing with the starters: http://youtu.be/N_gpIAfOrdo?t=3m35s

  • News - Enginursday: Yeah, I foun… | about 2 months ago

    The trouble with using turbines to provide mechanical power to cars is their rotational inertia and peak-y power band. They take too long to rev up, and only make respectable amounts of torque and power at high speeds. You could keep the engine at a high shaft RPM and apply fuel to keep it there as demand varies, but you would be wasting a lot of energy just pushing air around at low power levels (where automotive engines spend the great majority of their time) and would likely have issues with thermal cycling (uneven expansion and contraction of parts due to heating) as load varies. If I were going to try to use this turbine in a vehicle, I would go for an electric transmission - use the turbine to drive a generator (though 2-4x the voltage of the original generator head), which in turn would power a traction motor. Tossing some high charge/discharge rate batteries or (very) large super-caps in there would smooth out spikes in demand - improved throttle response for the driver and smoother load transitions for the engine - a hybrid turbine/electric system similar to what is seen in the automotive industry today with internal combustion engines.

  • Product ROB-10016 | about 7 months ago

    Overall dimensions of the plate are 60mm x 160mm x 3 mm. If one of the low-profile right-angle brackets are attached to the outer-most row of holes on the plate, it extends over the edge of the plate 2mm. If used in the same position, the taller right-angle brackets are flush with the edge of the plate.

  • Product KIT-11394 | about 2 years ago

    The CP2101 is a USB/UART chip similar to the FTDI unit found on Arduinos and the like. Looking at the wiring diagram, it’s set up to allow serial communication between a host computer and the ATmega uC. What functionality that provides, I don’t know… Perhaps the host system can control the generator over USB.

  • Product PRT-10473 | about 3 years ago

    There are literally dozens of different brands and models of chargers out there that seem to use this same core design. Some have an internal AC-DC power supply, others (like this one) just have a DC power jack. The specs and connector layout vary a little, but they’re pretty obviously all derived from one base design.
    I have a Supermate DC6 by Detrum. Same 16x2 display and 4 buttons on the front, power jack and servo-like connector on the left side, charge output banana jacks and balance connector on the right. As scicior mentioned above, it has a ATMEGA168 at it’s heart.
    As far as differences, the DC6 has a black-on-green display rather than white-on-blue, and only has the largest size balance connector on the charger itself… An adapter board and cable provides all the other sizes. The DC6 has a big sticker with dome-buttons (but still regular PCB-mount clickers underneath) rather than chromed metal buttons. Very minor differences really.

  • Product TOL-09672 | about 3 years ago

    Knocked off who? Hakko? Aoyue?
    Hakko has officially discontinued the 936. The price of a genuine station isn’t particularly hobbyist-friendly anyway. It might make sense to get the real thing if you solder on a daily basis, but not if you’re just doing odds and ends a couple times a month.
    Aoyue has been making knockoffs of Hakko products for some time now. I have one of their 968 hot air stations, which effectively includes the above soldering station. Its functional and its internal build quality seems perfectly reasonable, though it does have a few quirks; Making the lights flicker when the hot air heater is cycled on for instance (but it’s a real power hog).
    It wouldn’t surprise me in the least if Sparkfun simply contracted with Aoyue to badge their 936 knockoff with the Sparkfun logo. Aoyue gets a new outlet for their products, SF maybe gets some say in quality control, SF customers don’t have to explain their soldering station’s obviously asian brand name. Everyone’s happy.

  • Product TOL-10240 | about 3 years ago

    Good point. The regular spools are by weight, so you get a longer length of the thin stuff but the same total volume of solder. Measuring by length means the .032 sample contains about 2.5 times the volume of solder compared to the .020 sample (do the math… the number surprised me too).

  • Product DEV-10529 | about 3 years ago

    Judging from the pics, digital pins 2, 3 and 4.

    What pins does the shield take up?

  • Product PRT-09705 | about 4 years ago

    (anyway)
    I lump all of these chargers together because they appear to use the same core software/hardware package. The menu/info display screens are identical (though the color of the 16x2 character display varies) and they all have four functionally identical buttons lined up under said display. The functional specs also have very little variation.
    Personally, I bought a “Supermate DC6” through hobbypartz.com a month or so ago. While adding a cooling fan, I poked around a bit and found the controller chip: An SMT ATMEGA168 tucked away under the LCD display, though some effort had been made to scratch off the numbering. An unused pin header was also apparent, which might be left over from programming (I didn’t try to follow the traces to confirm). If these chargers are all as internally similar as i suspect they are, they could be interesting hacking fodder. Throw an Arduino bootloader in there (or not if you’re hardcore like that ^_^) and write your own charging software.

No public wish lists :(