My Delta Pulse not working - Power input Capacitors (4700uF 16V) Polarity changed by mistake.

[sunita.pradhan]

Hi Gurus/ Experts,
Need your help !!! I by mistake changed the polarity of 2 x 4700uF ( connected to battery Power).
Red led started glowing and some fumes came out near 1000uF, 16V & 10uF, 16v capacitors.
Pulse width trimmer not working with coil connected ( no power consumption change with multimeter (A) in series).
No metal detection on coil.. Earlier it was working fine . please help and advise.

[kt315]

gggoood. nice start. the pcb has to have a protection diode on unright polarity batt connection.
also in circuit must be a fuse, 5A. but... always, we know this fact in electronics...
there is not 'The Protection From The Fool'...

[sunita.pradhan]

I completely agree to what you say KT315. I have been reading your post regularly. I really appreciate your dedication towards this field.
I did this by mistake.. Now I need your advice if you can help me. thanks.

[sunita.pradhan]

this capacitor ( 10uF, 16v) found faulty. what else should I check ? Can anybody advice ?

[kt315]

strange for me. but its possible if you use 1N4148 vd8 vd9. you must check them.
i changed in my design them on 1N4001...06 because chinese diodes are lowcurrent crap.

[sunita.pradhan]

Today I checked 1N4148 diodes & also changed them with 1n4001 as guided.
checked all ICs vCC & GnD power. its around 10.77 to 10.78 volts. Theshold pot (in auto mode),Tuning( on manual mode) seems working fine as I can hear sound(tic tic) from speaker.
Also checked the D3 & D4 diodes, seems OK. But there is no detection happening on coil. what might be faulty ? is it the IRF840 MOSFET faulty or any any IC is faulty?

Can somebody help & guide me ?

[kt315]

why you not able to check mosfet by a tester?
i told about two version of it - like a KIT and like the tester. i have them both -!

https://www.geotech1.com/forums/album.php?albumid=113

[sunita.pradhan]

Thanks for the reply KT315 !! I will buy the tester. But what could be the possible faulty component/components as per you ?

[kt315]

do you have oscilloscope? set a probe on OUTPUT of pre amp and give a pic to here.
i can not say you what you burnt right now reading your texts.