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I normally design and make electronic projects but im into microcontrollers more.. I can fix almost any prob in a low voltage dc circuit, but inductors and high voltage transformers are totally new to me, and since this was my first smps repair attempt, i was totally lost as i didnt have an idea...
krypton and murali, thanks a lot for that help.. And yes, as you said, the supply is cycling.. Since i had replaced all ic's, i will have to check the zenner's caps and resistors.. There is only one metal film blue resistor, it seems ok, let me check the rest.. Any help regarding any details wud...
Hello,
Could somebody please help me, as this thing is getting on my nerves. I replaced all electrolytic capacitors on board, replaced the TL494 and LM339 IC's, replaced 13007 switching transistors, tested each and every diode and rectifier and zenner on it, tested all fusible resistors and...
Its a Frontech ATX 400W SMPS with model no JIL-2411.. Im replacing the caps today with higher valued ordinary ones as the caps on board have odd values like 1500uF 10V, so will be replacing with 2200uF 16/25V and low esr caps arent available here, so hope the good quality ordinary ones will...
Hmm.. seems good.. will try for one soon.. thanks!! also another help.. I have another smps which stopped working after running without a load, what could be the prob? all it gives is a 5v vsb.
I will be building one, but not now, as it will be usefull only for this one at the moment, so I'll try replacing the caps, but some caps have odd ratings like 1500uF, can I replace them with 2200uF's as thats the closest higher I can get?
The secondary has a lot of hi rated quick rectifier diodes, a bunch of low ESR capacitors and the feedback side has 1 controller chip, possibly along with a TL494 chip and it will be hooked up to an optocoupler wired to the switching elements on the primary. If the opto dies, the supply wont...
Now thats a good point! everyone says that sound is due to to caps on primary, but ur point makes more sense since I have checked the primary. For the caps on the secondary, I removed each cap out and charged them with a 9v battery, waited for 10 secs and connected to a dvm and it discharges...
That was a nice article, but its more focused on the primary side and I had fixed my primary side of the supply. The problem now is a short somewhere on the secondary, but wait let me check the 494 as stated in the articles by checking for +5v on pin 14.. thanks!
That looks nice, but pdf is secured and so unable to copy paste it to translator :( Thanks anyway!
I checked the smps again, all zenners are fine, all rectifiers are good, primary side is good, and all electrolytic caps and diodes are fine.. tested fusible resistors and all seems good, now what...
If you get any MOSFET amplifier with the power you need and a matching impedance, you could even consider placing it as a seperate amplifier outside the sub box. Placing a preamp close enough to a transformer will cause hum, sometimes grounding the input's ground to a real earth can solve hum...
Fixing a PC ATX SMPS
Hi all,
I have a 400W ATX smps lying around which I'm trying to repair to run an old motherboard. Got it from my cousin with the fuse blown off. On checking, I found that both 13007 switching transistors had blown out of which one was shorting the circuit. The bridge...
Re: SATA problem
First Enable sata controller in your BIOS. There may be native/Enhanced mode too, set it to native.
Normal motherboards have 4 SATA ports of which 2 are master and 2 slave. Connect it to a master port. Then power on the machine and check in BIOS if the device is recogonized by...
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