wayne burdick wrote: > I haven't heard any noise from them yet. Since they run directly from > 110 VAC, I imagine it's just a bridge rectifier, a resistor, and a > filter cap. I wouldn't expect any RF noise.
The LEDs need a constant current supply. Using a resistor to achieve that would significantly compromise power consumption. I would expect them to use a switch mode power supply, regulated for current, rather than voltage. That's how professional LED lighting drivers work. The electronics ought to be very similar to those in CFLs, but it will be easier to get a good ground plane. The current generation of LED bulbs are based on 3W or greater single devices, so a 6 watt device would only drop about 8 volts. A device that achieved 6 watts with large numbers of devices is obsolescent technology, although may well be all that is available on the consumer market (although, for specialised consumer markets, like bicycle headlamps, the state of the art devices are in use, as they are for commercial lighting). -- David Woolley Emails are not formal business letters, whatever businesses may want. RFC1855 says there should be an address here, but, in a world of spam, that is no longer good advice, as archive address hiding may not work. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
