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wb8nbs

Member Since: May 19, 2011

Country: United States

  • Can I power the RedBoard by backfeeding 5 volts into one of the pins on the Power connector (JP10)?

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  • Good question. Do you get more RFI from a switcher with a high voltage output or from one with low voltage output? Does Sparkfun have some kind of spectrum analyzer? Some of the products require part 15 testing?

    I have a floor lamp next to my man nest rocking chair here. The CFL I put in there pretty much killed the FM radio plugged into the same outlet. I put a .002 ufd across the lamp socket and that took most of it out.

  • Ya, I have a two meter FM rig in my garage about three feet from several LED bulbs. They make the radio almost useless.

  • Do us a favor, before you destroy bulbs that have switching power supplies, check them for RF interference. Place a radio tuned to a medium strength station a few feet from the socket and see if it affects reception. Not scientific, but you can compare different bulbs.

  • I used these green, yellow, red in a light box for the Toastmasters club. They have a person manually controlling the lights to tell the speaker when to shut up. I cut the lens off the tip of the LEDS at an angle to bend the light more to the front which worked well. Used a Dremel tool with cutoff disk, polished with 600 grit sandpaper then a buffing wheel for final polish. I noted the yellow LEDs at 20 milliamps were nowhere near as bright as the red at 15 ma or the green at 12 ma. Those currents were obtained from a 9 volt battery, with two LEDs in series with a 200 ohm resistor. https://dl.dropboxusercontent.com/u/40929640/TimerProject.mp4

  • I'm curious how large the backorder queue is after Arduino day.

  • http://www.schleuniger.com/
    But you probably can't afford one.
    When I worked for a Telco, the cable vendors were required to use a Schleuniger stripper.

  • In the June 2011 QST magazine, there is an article describing this DDS chip used in a synthesizer for old Ham transmitters. The circuit uses a simple LT1253 amplifier to buffer the DDS output which would be useful to incorporate on this Sparkfun board. He uses a PIC16F877 controller, I would like to know if it is possible to duplicate the circuit and software with an Arduino instead.
    There is a file of information at:
    http://www.arrl.org/files/file/QST%20Binaries/Jun2011/QS0611Lunsford.zip
    but you have to be a member to access.

No public wish lists :(