Member Since: September 26, 2008

Country: Canada

  • What size is the wire? How much current is it rated for?

  • Its not about a device failing. Its about devices interfering with life critical communications like air traffic control and navigation systems like GPS.

    Any device with an oscillator has the potential to jam communication. The range of the jamming will be very limited but in the right conditions it may cause problems on a world scale. Say you have a microcontroller operating at 8mhz and that 8mhz gets into a 1kw audio amplifier(that isn't properly designed) sitting on the shelf next to it and the speaker cables just happen to be a 1/4 wavelength at 8mhz. Even if only 1watt gets into that wire at 8mhz you could jam out HF for all trans Atlantic flights under the right propagation. I just pulled 8mhz out of no where. Usually HF ATC operates on several HF frequencies and change to the best one for that time of day. HF propagation is highly variable due to solar and atmospheric conditions.

    Just because your oscillator is running at X Mhz and nothing else is on that particular frequency doesn't mean your it won't interfere with communications. Your micro controller oscillator produces square waves which include the fundamental frequency plus lots and lots of higher frequency harmonics. Then there is intermod interference, where your device will mix with the oscillator of another device to produce harmonics all over the place. Sum of the frequencies, difference, sum of the square wave harmonics, etc...

    Then there is high powered PWM circuits, which make great radio jammers if they are no properly filtered and shielded.

    These rules are very important and must be enforced. Its more important for some devices(like high power) that others. In this age of digital communications its easy to forget that interference exist as you no longer hear it on the radio.

  • I'm slightly curious how these things are legal in the US seeing as how they can be tuned anywhere from 260-960Mhz. Is it exempt from FCC rules or something?

    The only legal way I know of to operate this thing outside of its original frequency is with an amateur radio licence and then only on 70cm and 23cm bands. I believe to operate on the ISM bands it would have to be approved by the FCC.

  • What temperature can the adhesive handle?

  • What are the power specs on these LED?

  • This would be much cooler if you guys didn't use the dreaded plastic clam shell.
    What would be really cool is if all the sparkfun packaging could be used as a project box. That way it would be more environmentally friendly. Also it would mean alot of projects would be sparkfun branded. I'm thinking something along the line of the plastic cases that math sets come in. Clear plastic top with knock outs for switches and buttons. The back should have mountings for many sparkfun boards and there should be a knock out for usb connectors.

  • If I wanted to use these for TTL serial do I need to cut the trace from the output of the SP3485 to the FT232RL?

  • What is the bandwidth of this board? Impedance?
    Could this be used to switch video? What about using 5 of them to switch RGBHV(Say XGA) video?

  • Its odd little sensors like this that keep me coming back to sparkfun. I don't even have a use for this thing but I'm going to put one on my next order.
    Hmm... maybe some sorta electronic game that you have to be alittle drunk to play...

No public wish lists :(