EAY60968801 (60968701) schematic

[paulstef]

Finally , after many many days I finished reverse engineering and repairing the two boards I had. The schematic is from the 60968801 but the ...701 is very similar.

Here is a link to a YT video explaining some details:
https://www.youtube.com/watch?v=NmifFBrB8BM

[budm]

Re: EAY60968801 (60968701) schematic

Please post the PDF of the SCH so we see the details better, thanks.

[paulstef]

Re: EAY60968801 (60968701) schematic

Please post the PDF of the SCH so we see the details better, thanks.

Ok, will do, once I'm back home.

[paulstef]

Re: EAY60968801 (60968701) schematic

I put a download link (google drive) in the description of the video.

[Peter Chiu]

Re: EAY60968801 (60968701) schematic

Love your video, ( the BEST educational video, I've ever seen ! ). Can you make more videos ?...... Please.......


I'm dedicating this song to you.
https://www.youtube.com/watch?v=4DO8GsIYfhQ

Did you drown the diagram by yourself ?
now a day, everybody just change the board. Nobody will spend time to troubleshooting anymore .....I admire you, I will never find that resistor by myself...... Good job ......

But ....but....you need to take down your picture ,I don't thing that 's good for kids to copy..............just friendly reminder.......

[paulstef]

Re: EAY60968801 (60968701) schematic

Love your video, ( the BEST educational video, I've ever seen ! ). Can you make more videos ?...... Please.......


I'm dedicating this song to you.
https://www.youtube.com/watch?v=4DO8GsIYfhQ

Did you drown the diagram by yourself ?
now a day, everybody just change the board. Nobody will spend time to troubleshooting anymore .....I admire you, I will never find that resistor by myself...... Good job ......

Yes I drew it myself, I used EAGLE for it.
It's very time consuming and therefore almost never justified nowadays. I wish consumer electronics prices were the same they were 15 years ago.

Would be good for us ... (and bad for everybody else)

[Peter Chiu]

Re: EAY60968801 (60968701) schematic

In school teach want us, put two finger to the AC 110v ,for about 30 sec to pass the test.
The secret is .....you gonna put thumb and index finger to the 110v at same time , current will make a loop .......never touch by only one finger.....So.... Sorry .......you're right again........because you use two fingers to make a safe loop.......

[4CX250]

Re: EAY60968801 (60968701) schematic

Hello Lads, nice to met you all.

First, my compliments to Paulstef, your good work on the schematic and video helps make the impossible, possible, well done Paulstef!

Had the usual clicking relays problem, though the cause was not usual suspects.

With Paulstef schematic, the KA2431 shunt reg ic was going into parasitic oscillations within 20 minutes to 20 seconds of switch on, dependent how long a time delay between power application from the mains.

Bit of digging on application data from the manufacturer of the KA2431 , AC gain stability characteristics require a 100nF capy Anode to Cathode, and so it was after 8 hours, fault chasing, chip capy 100nF fitted, the PSU now powers up reliably.

More to the story, yet it conveys an unusual "repair and factory design issue".

Regards to all.

[paulstef]

Re: EAY60968801 (60968701) schematic

Bit of digging on application data from the manufacturer of the KA2431 , AC gain stability characteristics require a 100nF capy Anode to Cathode, and so it was after 8 hours, fault chasing, chip cappy 100nF fitted, the PSU now powers up reliably.

Thanks for sharing.

[4CX250]

Re: EAY60968801 (60968701) schematic

Thank you Paul. The 3BR1565 was going into power save mode on its own it appeared, which had me perplexed at first.

Going to order a bunch of TLV431 to replace the KA2431, cheaper buying 50 than a few. Should work, as set output from ref formula is identical, if not the lesser drive capabilities of the TLV over the KA part. Not that onerous a demand the feedback loop opto led.

Regards to all.

[4CX250]

Re: EAY60968801 (60968701) schematic

Update, the bypass capacitor ( as recommended by the chip manufacturer ) has cured the power supply shut down issue. Did order the TLV431 just in case, no need to fit it as yet. Regards to all.