There are these types of mosquito killer racket are easily available in market at some 150 rupees.
This consist an electric fence in the bat portion which has 5000-10,000 volts passing through them. This is not only mosquito repellent, it’s insect zapper. When a mosquito gets in contact the high voltage burns it. The inner circuit consists of battery, a charging unit, and a HV inverter circuit, which I’m going to describe here.
Coil turns will be as described in text and not the one indicated in this tmage.
The circuit consists of a flyback topology transformer driven by a general NPN transistor 2SD965. The feedback coil of transformer is of 10 turns, the primary is of 40 turns and the output or secondary coil is of 450 turns. When this circuit is run by 3Volts, the transformer generates about 2000-4000 volts at zero load, and the output is then coupled 3 times by using 3 IN4007 diodes and suitable capacitors, thus reaching our need of 5000-10,000 volts.
Note: All diodes used in circuit are IN4007 diode, The transistor is 2SD965, and can’t be replaced by BC548, The transformer should be ferrite core.
Below an actual circuit board found in mosquito zapper rackets.
umeysh says
Hello
Arup
I purchased a racket
but inside the racket is 2.4v 600mah Battery
I want to do more high voltage
I want to use 9v 1A battery
is it possible ?
Prasenjit Deb says
helo mr arup,
glad to find such expert advice here. but unfortunately, i m still unable to guess my problem. symptoms:
1. sound of oscillation occurs once in a while. it's been more than a month now and i have heard the same only twice or thrice!
2. all the led glows, but doesn't kill the mosquito as it did the very first day! but sometimes, it does kill one or two with a huge spark. rest of the times, the mosquito does get trapped in but doesn't blast with a spark!
3. checked the o/p with a tester, it sparks well enough!
4. i have been charging the batteries for hours to see if dat works, but to no use!
5. checked the transistor, found ok!
6. checked the transformer, found ok!
and finally after reading all ur comments, i am highly confused!
pliz help me..
thanks in advance 🙂
Arup says
........and finally after reading all ur comments, i am highly confused!
I'm too confused. You can send it to me for diagnostics though. 🙂
vignesh says
I need to use this mosquito bat for scientific research. The application requires some sort of tweezers to be used to produce high voltage and needs to be applied to some living cells (electroporation). But i would apply the voltage to a solution which will conduct electricity. Is there any possibility of lethal accidents? what should i do?
Arup says
Not much risk if you take general precautions.
Rajesh kumar Rajesh says
arup sir
why you not give the circuit of transformerless power supply in YRD bat set?-Rajesh C.G.
dewa says
Hi arup, my lucky found your blog, can u make this thing for killing rat/mouse? how will the circuit be? I bored with rat in my house. the work is it will zap the rat when they come into the trap and die. please use rechargeable battery 6 or 9 volt. thanks
Arup says
If you kill rat by the method, there will be odour of burning of the rat. So, don't go for that.
Mohan says
hello Sir, i have mosquito racket . it is not operating , i opened the handle and checked Transformer is working . Litle sound is also comming from small transformer. Wire is properly soldered with net . i ithink Currest is not reaching to Net . How to find the problem . Racket is in new condition .... i donot know much about electronics. __
Arup says
Check every connection.
Short racket fence using tester to check if spark comes.
gautam says
hi. I want my racket to work on the regular home electricity supply replacing the battery . How to do it
Ajay Chowdhary says
Dear Anup, I saw your site and very much impressed with your efforts to solve the problems of each and every body. May Maa Kali give you many many blessings for your endeavours.
My problem is that I purchased racket just 4-5 days back. Suddenly it stopped working. On touching Screw Driver on inside net it sparks, but the not very powerful as compared to when it was purchased. All lights are working fine, I charged it for 8 hours but still no difference. Please suggest me what to do.
Arup says
It can be many reasons. Check battery voltage. Probably battery is not holding charge properly.
Techno says
Ok i am about to make a 10x Voltage multiplier circuit (using 2000kv 100nF capacitors,diodes)
I was about to use EI-14 audio transformer (1k:8R)centre tap type...but can i use the transformer used in this racket instead?? Will it work?
Arup says
I'm not sure, but it should work.
SRIKANTH says
good
ajay baharadwaj says
Sir,
Can we make the net bigger so that it can cover the complete windoe.
Ajay.
Arup says
Yes you can. Just increase another couple of capacitor/diodes to increase voltage if sparks are low.
abi says
sir i just bought my mosquito bat it has been working good 2 days back but now it doesn't kill any mosquitoes and the LED also doesn,t glow what could be the problem could you suggest an idea for me to repair it
Arup says
Open and check battery, and look for burnt parts.
aryan says
output of my bat is 2000v can i able to convert it to 220-240v by using step down transformer so that we can able to light a bulb.Is this is possible or not..............and i am new to elctronics..........
Arup says
Not possible because it emits very less current.
amol gupta says
arup i wanna knw dat led is lighting but the current is not reaching till it 's net.. wat can be the reason for this. n wat the brown wax coated things are called n how it can b checked. ??
Regards
AMOL
Arup says
Brown wax coated things!!
prasad says
sir, in my racket the transformer has gone...can we change that
Arup says
Buy one from market and replace the old one.
Udayan says
What is the specification of the o/p transformer?
Udayan says
Can you provide me with a circuit for a fixed fence working with a 6 volt battery
Arup says
This circuit can work in 6V as well