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I am interested in the voltage used in electrical fly killers - does anyone know (no speculation please) the voltages generally employed? To be clear, I am talking about mains powered, wall-mounted devices.

I would also be interested in the general topologies used - I am guessing some sort of self-resonant flyback with an unrectified output. Anyone know for sure? I haven't pulled one apart yet...

stefandz
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    http://www.brighthubengineering.com/diy-electronics-devices/107500-indoor-mosquito-bats-explained/ – Eugene Sh. Jan 22 '16 at 16:17
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    I have one with a coil directly wired to the plug; 230V (UK mains) – CharlieHanson Jan 22 '16 at 16:21
  • Thanks @EugeneSh. - I realise I left some critical details out of my original question. Best I can tell from your link is <630Vpk , but useful all the same. Thanks. – stefandz Jan 22 '16 at 16:21
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    I have seen 120V ones and I have seen 1.2kV ones. There is no definite answer - It highly depends on the type and manufacturer. – DerStrom8 Jan 22 '16 at 16:24
  • How many volts kills (or permanently inhibits) a fly is the real question hiding beneath. – Andy aka Jan 22 '16 at 16:41
  • @Andyaka not quite - that's a factor in design, I am more interested in what exists already. Not looking to roll my own, simply to reappropriate what exists. I would wager it's mA (or uA) that kills or inhibits at the biological level, with impulse energy / temperature rise causing explosion taking over for team physics at higher power / smaller fly level. – stefandz Jan 22 '16 at 16:44
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    Flyback seems appropriate. Will web-apps eventually replace these? – Transistor Jan 22 '16 at 16:47
  • The point I'm trying to make is the fly-kill voltage is the base minimum and actual devices will be this voltage plus a bit (or a lot more). – Andy aka Jan 22 '16 at 16:47
  • @Anday aka Ah but how many volts produce the satisfying sound and light show that will keep customers coming back to buy more zappers? – candied_orange Jan 22 '16 at 19:59
  • I suspect that those wall-mounted ones are extreme overkill for a fly. I've seen a handheld swatter-shaped one powered by a pair of AA batteries in the handle and even that is fairly effective. Also, the wall-mounted ones are usually equipped with a UV light source that attracts the flies to it in the first place, so a lot of the power may be going to that and not the fly-murdering parts. – Darrel Hoffman Jan 22 '16 at 21:04

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I visited a factory making the 50/60Hz transformer type some years ago. They were several kV (3-4kV) and similar in construction to ballast transformers for neon signs, but without the magnetic shunts to increase the output impedance.

These ones create quite a profound arc which is intended to burn the insect off the grids. Here's a photo of one from Alibaba:

enter image description here

Spehro Pefhany
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One which I repaired once used rectified 240V mains with a doubler, so about 680V

user1582568
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Here's a teardown video of a cheap plug-in type, which uses voltage doublers to product -630V and +630V across the grid:

https://www.youtube.com/watch?v=LtXmsxRdiUw

grahamparks
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