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tabbypurr@gmail.com: Mar 18 02:46PM -0700 > Let your conscience be your guide.   > Peter Wieck > Melrose Park, PA   Interesting. That's at odds with my limited experience of them. Both uv tube with kilovolts & halogen lamp with hot bit removed the majority of flying insects indoors when I used them. What percentage were mozzies I don't know, houseflies were the main issue & catch.   I'm puzzled too by the talk of yards. Surely they weren't using them outdoors? If so no wonder they didn't achieve anything.     NT

Look165 <look165@numericable.fr>: Mar 18 11:52PM +0100 Insects are attracted by warmth, not light. So any gadget won't win.   Jeroni Paul a écrit le 16/03/2019 à 02:54 :

John-Del <ohger1s@gmail.com>: Mar 19 04:37AM -0700 On Monday, March 18, 2019 at 6:52:24 PM UTC-4, Look165 wrote: > Insects are attracted by warmth, not light. > So any gadget won't win.   Yeah, but insects like mosquitoes "see" heat, and most light sources emit light in the infrared band.

Martin Gregorie <martin@mydomain.invalid>: Mar 19 11:47AM On Tue, 19 Mar 2019 04:37:50 -0700, John-Del wrote:   >> So any gadget won't win.   > Yeah, but insects like mosquitoes "see" heat, and most light sources > emit light in the infrared band.   It seems that mosquitoes initially follow CO2-rich airflows to find food sources, switching to warmth/moisture/odour vectors as they home in, and finally using eyesight to find the best place for tapping into the victim's blood supply.   Several information sources say this: none say they use long-range optical or IR methods of finding their next meal.   -- Martin | martin at Gregorie | gregorie dot org

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 19 05:08AM -0700 I am going to get a bit snarky here, as there is an entire class of the population that are so confused by actual facts that they *MUST* believe the opposite, or they will die.   a) Mosquitoes are poor flyers - generally as little as a 5 mph wind will give them difficulties. A breeze/fan is your best local defense. b) Mosquitoes follow CO2, various scents and such in searching for their prey. Although they prefer warm-blooded prey, they will readily bite reptiles and amphibians should nothing else be available. c) Some individuals attract mosquitoes more than others. But anything that breaths with lungs is fair game.   Mosquitoes ARE NOT attracted to light. FULL STOP. If they get caught in a zapper-type trap, it will be mostly males (which feed on sap and nectar) or females caught simply passing through, not heading to a destination.   Zappers may be entertaining, but they are a plague on the insect population, doing far more harm than good - excepting those indoors, in kitchens and such, that kill mostly flies. The brute fact of the matter is that these devices should be banned to the general public, and used only by license. As, clearly, the general public is far too stupid to understand the issue - requiring a nanny-government to protect them.   No Bumblebees - no vine squash or melons. No Bees - not much of anything. No hummingbirds (protein source: Fruitflies, spiders and other small bugs, mostly), many fruits with tubular flowers would fail. Moths, butterflies, midges, beetles - by the way, no midges (often mistaken for mosquitoes), no chocolate.   Insects are at the bottom of the food chain - and the base of the pyramid on which much other life is based.   It is interesting to note that the mosquito, while widespread and pernicious, is one of the few insects that does not seem to occupy an important place in the food chain. Really. And, one of the few that is also immune to most conventional attractants. Go figure.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Mar 19 05:31AM -0700 > Zappers may be entertaining, but they are a plague on the insect population, doing far more harm than good - excepting those indoors, in kitchens and such, that kill mostly flies.   ... which is precisely where they are used.     NT

Tim R <timothy42b@aol.com>: Mar 19 05:47AM -0700 > I am going to get a bit snarky here, as there is an entire class of the population that are so confused by actual facts that they *MUST* believe the opposite, or they will die.   > a) Mosquitoes are poor flyers - generally as little as a 5 mph wind will give them difficulties. A breeze/fan is your best local defense. > b) Mosquitoes follow CO2, various scents and such in searching for their prey. Although they prefer warm-blooded prey, they will readily bite reptiles and amphibians should nothing else be available.   This is very old data, it's what the grad student working on his dissertation on mosquitos told me in college, and that was 1971. So there may be newer info, or he may have been wrong. There is as usual no chance I've remembered wrong! <humor>   But he said mosquitos were not attracted to CO2, but activated by it. CO2 just increased their random flying speed, causing them to be more likely to come into proximity to a warm blooded critter. He also said repellents didn't repel, but just made it harder for them to find you, so if the density was such they would bump into you anyway you were toast. (that was certainly true on a camping trip to Canada.)

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 19 06:09AM -0700 On Tuesday, March 19, 2019 at 8:47:48 AM UTC-4, Tim R wrote:   > This is very old data, it's what the grad student working on his dissertation on mosquitos told me in college, and that was 1971. So there may be newer info, or he may have been wrong.   That the data is old does not make it inaccurate. What has changed is how refined modern mosquito traps operate - which is by a combination of CO2 and heat - just like warm-blooded prey; and how repellents have also been refined.   DEET (N,N-Diethyl-meta-toluamide) does, in fact, confuse the mosquito such that it has a hard time landing in order to bite. And in sufficient concentration (actual contact) it will kill them. But, it and many other oils such as eucalyptus, pennyroyal and similar do have actual repellent properties - mosquitoes do actually hate the smell. As the non-DEET materials do not cause confusion, they are poor substitutes in actual practice.   By the way, all the modern traps do is act like a REALLY BIG and attractive lure - and so should be placed some considerable distance, and slightly downwind of the area to be protected. Otherwise, they will act as an invitation to the party.   And, we have Metofluthrin these days, which is a pyrethroid (plant-based) neurotoxin that is a specialized repellent pretty much only for mosquitoes.   Point being that none of this makes bug zappers any more benign.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Mar 19 07:01AM -0700 > Point being that none of this makes bug zappers any more benign.   > Peter Wieck > Melrose Park, PA   Using bug zappers outdoors makes about as much sense as having a gas heater outdoors. Even so they could only catch a tiny percentage of the world's insects that way.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 19 07:14AM -0700 > Using bug zappers outdoors makes about as much sense as having a gas heater outdoors. Even so they could only catch a tiny percentage of the world's insects that way.   Actually, they, together with habitat change and such things as lawn services (Chemlawn and such) are threatening entire local ecosystems.

Spare Change <noncompliant@notcompliant.zgq>: Mar 18 10:23PM -0700 It's a TS-1000-124A, a "true sine", 120VAC 1000W output, 24VDC input:   https://www.meanwell.com/webapp/product/search.aspx?prod=TS-1000   I'm looking for a schematic of this or other Meanwell sine inverter.   Anyone familiar with how similar these Meanwell sine inverter input voltage stages are (rectification & input to the "chopper")? Would a 24VDC unit work on 12VDC? Or might these boards be made for several DC voltages and populate (or not) certain components?   I don't have the unit but am contemplating that it may somehow be useful on 12v, maybe derated.   Thanks.

Winfield Hill <hill@rowland.harvard.edu>: Mar 19 04:53AM -0700 Spare Change wrote...   > I don't have the unit but am contemplating that > it may somehow be useful on 12v, maybe derated.   Why not buy one of the 12V models?     -- Thanks, - Win

Terry Schwartz <tschw10117@aol.com>: Mar 18 03:07PM -0700 On Sunday, March 17, 2019 at 8:05:19 PM UTC-5, Fox's Mercantile wrote: > Jeff-1.0 > WA6FWi > http:foxsmercantile.com   Oldstuff.... Oldschool.... Oldshit.... I have a memory block when it comes to this dolt.

dplatt@coop.radagast.org (Dave Platt): Mar 18 12:46PM -0700 In article <q6k9hk$maf$1@dont-email.me>, >Blackpool Rock candy sticks, where the writing went all the way through >from one end to the other) and drawing down a preform through a >succession of wire dies. For solder, drawing down would be my guess.   I believe your guess is correct. I saw a marketing blurb by Ersin Multicore, talking about their process, and they specifically mentioned the use of a progressively-smaller series of dies.   They said that some "fake" multi-core solder (by their competitors) uses a single nozzle with five openings to extrude the flux. Although they didn't say so specifically, this implies to me that their own process uses five separate nozzles as part of the initial extrusion process.

tabbypurr@gmail.com: Mar 18 02:49PM -0700 On Monday, 18 March 2019 20:08:08 UTC, Dave Platt wrote: > mentioned the use of a progressively-smaller series of dies.   > They said that some "fake" multi-core solder (by their competitors) > uses a single nozzle with five openings to extrude the flux. Although   there's more than 1 way to interpret that.   > they didn't say so specifically, this implies to me that their own > process uses five separate nozzles as part of the initial extrusion > process.   surely it doesn't imply that. Any why and in what sense would another mfrs 5 core solder be 'fake'?     NT

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