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N_Cook <diverse@tcp.co.uk>: Jan 30 11:10AM Poundland, so 1GBP per lamp, now have 3 LED 2.6W 4000k mains lamps, that come apart with 2x3 screws, easily removed 3 LEDs, 3 separate condenser/focus lenses and for good measure 3.3uF,400V cap

Cursitor Doom <curd@notformail.com>: Jan 29 11:26PM On Thu, 28 Jan 2016 16:40:00 -0500, legg wrote:     > You won't want to hook it up and disconnect it every time you need to > switch over.   > RL   Sounds like a useful addition to any test bench. I've probably already got a suitable transformer lying around waiting for just such a project. Plus no shortage of "uncommitted oscilloscopes." :)

ggherold@gmail.com: Jan 29 01:06PM -0800 On Wednesday, January 27, 2016 at 5:53:16 PM UTC-5, ذكريات حسن wrote: > I have checked the water level, interlock, and tube pressure, and every thing is ok. Also, I think there is no problem with the resistance of the four fuses in the power supply.   > Is there any way to fix this laser without changing the laser tube? > Thanks   Cue Sam Goldwasser, you might look here, http://www.repairfaq.org/sam/laserfaq.htm#faqtoc And try your question at sci.optics   George H.

Tim R <timothy42b@aol.com>: Jan 29 10:34AM -0800 There is a street light I pass frequently that occasionally flashes like a strobe.   I've seen a bright flash at that corner a number of times over the past year or two, but never saw the source. Usually there's a building blocking it and all I see is the street light up.   This past week I was coming from the other direction and clearly saw the street light flash twice, very brightly.   These lights are bluish white, I've always assumed they were mercury vapor, but don't really know. It's not a city likely to have moved to LED.   Is there a failure mode for a discharge lamp that would produce that?

dplatt@coop.radagast.org (Dave Platt): Jan 29 11:48AM -0800 >These lights are bluish white, I've always assumed they were mercury vapor, but don't really know. It's not a city >likely to have moved to LED.   >Is there a failure mode for a discharge lamp that would produce that?   High-pressure sodium lights exhibit a "cycling" on-and-off behavior when they reach end of life. However, when I've seen this it's been a fairly slow cycle, and didn't exhibit the sort of bright strobe-like flash you describe.   I suppose that you could be seeing a mercury-vapor lamp with a failing bulb and/or ballast, where the ballast sends a strong pulse to "strike" the lamp and get the arc flowing (hence the flash) and a fault in the bulb causes an over-current or under-current condition which then shuts down the arc almost immediately.   Pragmatically, you might want to write down the streetlamp pole number (if it has one) and contact the city's public-works department and report the problem.

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