5 Insect Zapper suddenly failed to light up.
I bought this very effective but cheap (inexpensive) USB insect zapper. It suddenly failed. I have an identical one and after comparing components on both I came to the conclusion that a small smd chip, apparently a voltage regulator, burnt out.
The unit has 4 UV LED mounted on the board. The voltage regulator smd has ML8 printed on it. I cannot find this anywhere online so I do not know what characteristics to look for to find a suitable replacement.
Can anyone help me?
Whilst testing it, I must have been zapped myself from the coil of wire suggesting that the zapper itself still works but the LEDs do not light up.
The arrow points to the component I need to replace.
Thanks in anticipation.
Update (08/21/24)
I may be wrong in how I am testing these components. I might be wrong in my deduction earlier.
I have tested again and found that R3 (226) shows a reading of 4.85 MOhm. Shouldn't this be 22 MOhm?
Also C2 is giving no reading.
C1 shows 0.43 nF.
R2 (470) shows 48 Ohm
R1 (512) shows 5.08 kOhm
crwdns2934109:0crwdne2934109:0
crwdns2944067:08crwdne2944067:0
Hi @markbugejamd
Are you measuring the components "out of circuit" i.e. are they disconnected from the board?
If you're measuring them in situ you may get false readings due to parallel paths etc around the component caused by them still being connected to the other components.
Did you use either the capacitance test of a DMM to test the capacitor "out of circuit" or an LC tester that that allows for testing of inductors and capacitors "in circuit" to measure the capacitor? Again if not then you'll get incorrect readings.
crwdns2934271:0crwdnd2934271:0 jayeff crwdne2934271:0
I am aware of that....
For me, it is not easy to remove each and every component without risking damaging the board. Been there, done that.
This is the drawback of trying to troubleshoot and repair modern gadgets, unfortunately. Components are far too small and many times the boards are multi-layered to boot.
crwdns2934271:0crwdnd2934271:0 Mark Bugeja MD crwdne2934271:0
Furthermore, had I to try and replacing individual suspicious components, I need to buy and stock up a lot of components making it not worth one's while. Costly and some components difficult to identify correctly and find.
I was hoping someone might suggest the commonest possible fault from some previous experience.
crwdns2934271:0crwdnd2934271:0 Mark Bugeja MD crwdne2934271:0
I think my initial assumption was wrong as the zapper wires seem to be receiving current as I felt the zap. But then again I don't know how this component feeds the circuit (a) the zapper (b) the LEDs. May it is faulty as far the LEDs supply in concerned.
So the circuitry seems to be intact as far as current going through in an ac form, stepped up by the transformer and supplying the wires. The part involving the LEDs seems to be the damaged section of the circuitry.
crwdns2934271:0crwdnd2934271:0 Mark Bugeja MD crwdne2934271:0
Is it me or do D1 D2 D3 look dodgy. Or is just shadow.
crwdns2934271:0crwdnd2934271:0 Daniel crwdne2934271:0
crwdns2934275:03crwdne2934275:0