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Member #34964

Member Since: March 14, 2008

Country: United States

  • I know this is just copied from the datasheet, but “Extended spurious over 240 Hz…”? Maybe “Extended spurious frequency rejection over 240 Hz…”?

    Could the geophone be combined with this or this to create a through-earth communication system? Does anyone know the sound velocity characteristics of concrete or limestone?

  • What’s the production quality like? From the photos of the one board, it looks like there is too much solder on the SMD parts, some components are not mounted squarely, and they didn’t snap off the headers very cleanly. Are all the boards like this?

  • Connecting batteries in parallel isn’t recommended. They aren’t ideal voltage sources and differences in voltage (due to brand, age, manufacturing, etc) can cause the higher voltage batteries to discharge into the lower voltage batteries.

  • Another option is to connect your pull-up resistor to another MCU pin instead of directly to Vcc.<br />
    <br />
    Benefit:<br />
    + You can switch power to your pull-up resistor so that you aren’t always drawing current, even when you aren’t reading that pin.<br />
    <br />
    Draw backs:<br />
    - It takes up another MCU pin.<br />
    - Not very useful for asynchronous or interrupt-driven pins.

  • I would buy 5-10 of these if they were in the $15-$20 range and a matching step-up was available.

  • It looks like the manufacturer, Hanwei, also makes many other sensors. Could you carry ones for O2 and H2S specifically? I’d like to make a personal air-quality monitor.