Implementation of a simple number counter for a mosquito zapper


Joined Aug 1, 2013
NOTE - this is a *concept* schematic. I have not done stored energy or transient impedance calculations. There might have to be a resistor between C1 and D1 to limit the transient current and prevent D1 from shorting out the killing current. C1 must be rated for at least 2 kV.

Update: It might not be necessary for the Arduino GND to be tied directly to the return for the 2 kV. Isolation amps and isolated gate drivers use two capacitors for complete galvanic isolation. Hmmm ...


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Audioguru again

Joined Oct 21, 2019
In my Canadian city there used to be many mosquitoes and bats flying around. Now most of the mosquitoes and bats that eat them are gone. Each year my city puts larvicide in all the drains and ponds. They mark each done drain with a drop of paint with a different color each year to make sure they are all done. The larvicide is safe for wildlife.


Joined Oct 11, 2019
You could use the grid of the zapper. Its pretty much a switch. The center grid is positive, the front and back grids are negative.

Maybe Something like a logic probe circuit. Or a high K resistor on the positive wire.


Joined Nov 11, 2019
Why would the grid of a big zapper be DC instead of AC?
I figured he's talking about a battery powered tennis-racket style zapper. These just use a HV capacitor. And regarding the jokes about getting multiple bugs in one zap, I don't think that would really be possible, or at least it's extremely unlikely. There may be 5 other bugs flying through the grid unharmed, as the capacitor recharges. The one I have seems to recharge about 5 times/second. I do think this counter is a fun idea. How about a Hall effect transducer on one of the HV leads?


Joined Oct 11, 2019
The may mine worked i think was dc. Its for saftey purposes. The insect is the switch between the ground and positive. Bit like touching the ends of a big capacitors.


Joined Oct 3, 2010
I made a high voltage insulation fault detector several years ago, and if i remember correctly I used an optocoupler with the LED side in series with the high voltage. When any current flows, there will be an output.

here is that project. You can see the optocoupler I used and the circuit. Should hopefully give some illustration of the concept.

I just visited my link to the optocoupler and found that it is no longer a valid link. The part number was HCPL-4731. No longer in production. You can still find the datasheet though, and find an equivalent.
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