Neon bulbs don't have a long life span, and for alarm type applications=20 that's important. Also the neons blacken with age reducing light output.=20 I don't understand where 120/240 volt LED units are not readily=20 available considering everything. I have a 240 volt backup residential=20 hot water heater, don't want to use neons, space limited (The LED setup=20 below would fit and will breadboard one in the near future), but would=20 rather buy a UL rated product. On 8/30/2012 3:53 AM, Paul Anderson wrote: > Perhaps in this application a small neon bulb is more appropriate? > > -------- > Paul Anderson -- VE3HOP > > On 2012-08-27, at 7:42 PM, Mark Hanchey wrote: > >>> >>> >> This is one of those things that can be done but shouldn't be done. >> Really to do it right the cost is pretty high compared to just using DC. >> Capacitors at the rated voltages are not cheap, at least for the good on= es. >> A .47uf , 250V cap and a 1K, 1W resistor in parallel with each other and >> the LED connected in series across that connection will work for >> powering LED. I have seen bridge rectifiers built out of LED for low >> voltage demonstrations. >> >> Mark >> >> --=20 >> http://www.piclist.com PIC/SX FAQ& list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .