Samsung B4K-50 PSU

[Tommy100]

Hi guys, sorry to duplicate a thread.
I have posted on https://www.badcaps.net/forum/showthread.php?t=8831 as well, this is just a Bump.

My PSU has exactly the same damage, and I do not know if IC2 is avalable in South Africa.

Does anyone know what the Output Voltage is of the Standby supply?
I have a nice small Casio printer SMPSU that gives 24V 0.8A and I would like to use it as Aux supply. (with the blown components and Primary and secondary rectifier / Caps removed.)

If anyone has a copy of the psu cct diagram they can share It would be most appreciated.

Thank You.
Tom.

[PowerAmpFreak]

Re: Samsung B4K-50 PSU

The chip is probably the ICE2A280, not IEC2A280 that incorrectly stated in your other thred.

[Tommy100]

Re: Samsung B4K-50 PSU

Removed all the blown components and ones that look like they might pull down an external supply.

If I remove D28 on the Secondary of the Transformer and apply 5Volt to the smoothing cap, I can get the remote / power light to come on and switch with the front panel.

But nothing else happens power wise. The Aux supply seems to feed a 18V Regulator, but I cannot feed it from a bench supply as the negative of that section is hot.

The printer supply I wanted to use cannot supply sufficient current so another plan is needed.

It seems the repair shop in my Area replace the whole B4K and do not do component level repairs.

The ICE2A280Z seems to be unobtainable here in za. Sighs..

[Tommy100]

Re: Samsung B4K-50 PSU

Removed the 18V regulator and used a HP Printer supply 18V. It is a smpsu and the secondary is well isolated now all I need is a sturdy Compaq 5V charger, tidy up the mods and its tv time!

[Tommy100]

Re: Samsung B4K-50 PSU

Used a 18V Compaq supply with an lm7805 on heat sync, the heat sync can be earthed for neg, and the 5V connected to where D28 was, C39+.
Neg from the supply was put on C39-.

The HP Printer 18V supply Secondary is well insulated and it was connected to where IC8 was. + to output of IC8 and neg to the earth, center leg.

The input supply was taken from across CX4S pins.

Both smpsu`s used have built in fuses.

The only function that is not working is the standby relay, dont know why. But the set switches on nicely starting in standby, with the led yellow.
Then the front panel switch or remote can be used to switch on.

To switch off, I switch to standby, then power down.

Well this was a Bush repair. :p But its working, so happiness is.
Cheers.
Tom.

[Tommy100]

Re: Samsung B4K-50 PSU

The two units were mounted above the main psu, but its a bit hot there. They are not obstructing the flow from the Heat syncs. Its just warm up there with the lid closed, so I will put in 2 Boxer fans till The components can be scourced.

[trosdepep]

Re: Samsung B4K-50 PSU

Hey!!! Tommy100, I have same problema than you. I explained my problem on thread that you mentions on first post.
I solved the problema using your invention
Now tv Works perfectly and I have solved the problem of standby relay to open and close. Now is not heated in standby mode.

Is very easy. I´ve connected a 19v psu to the cathode of D25 instead of connecting a 18v psu on IC8

[Tommy100]

Re: Samsung B4K-50 PSU

happy days! Mine is still working as well!