Fixing a Flyback Supply that has Audible Noise

[@gaynzz6841]

Very nice presentation. One thing to add, all these things only fix symptoms. Fix the cause: Change the switching frequency to outside the human hearing range (>20 kHz)

[@zhitailiu3876]

Wow, this is really a great tutorial!!!! Thanks! Love PI!

[@sadunnakipoglu9471]

شرح مفصل جميل وروعه شكرا من تركيا .

[@Chupacabras222]

Very informative. Thank you.

[@walterbrown8694]

If replacing a single filter capacitor with several smaller ones in parallel, I would suggest using several caps, each with a different capacitance` - Maybe select 3 to give an audible C major chord (C, E, G)

[@sam-mr9nz]

Thanks for the information

[@Z-Ack]

I have a flybck psu that outputs just fine powering a fan on a ptc heater circuit so its just taking mains to 12v. However randomly it will stop outputting any voltage and make the higher pitched noise when powered up. When powered down it will audibly go from high pitched noise stepping down with the electrolytic cap drain.. cant figure out why the psu will stop outoutting intermittently.. if i wait a few minutes it will start working again and sometimes keeps working for hours continuously. Other times it will work for a few minutes then suddenly stop. The sound will be there every time it stops sounding like a motor that is not getting enough power to start but will be just barely causing the fan to rotate.. if at all.. so its not a zero output but likely a fluctuating noisy lower output.. could it be a cold solder or xformer with an output that shorts out with heat or something? Maybe a ceramic cap that has shitty solder joint not making full contact? Fault is not showing itself being intermittent and testing while fault is present is impossible due to the fault seemingly fixing itself. Ive tried physically impacting the circuit which never fixes or causes the fault. Ive set the board on a heater for soldering and fault does not happen, ive blasted with cold co2 to freeze and fault doesnt appear.. my only thought left is an oscillation either in the load causing the drop or on the ac side of the psu..

[@mathewselvam4961]

Very useful thank you 🙏

[@khalillabban7428]

Thank you

[@nfcradio4622]

I want to know more about Pi expert Component Library Magnetic Data Base. The terminology use to add user ferrite core is very unclear few of term I know like AL nH/T^2 , but term like SA mm^2 what does it means it is surface area or what ? I request you to pl. provide me all terminology for core and bobbin which picture explaining it. AE mm^2 , AE min mm^2 ect. for core and bobbin.

[@kadircinkaya]

💯❤