Akai 42" Plasma Power Supply - Photos Inside

[mynamiseli]

Hello badcaps. Long-time lurker, first-time poster.

A 42" Akai Plasma (Model PDP4294) has come into my possession from an unfortunate friend who was tired of sinking money into it. He recently had the Y-Sus replaced by a local repair shop (at $400 clams, ouch) and suspected he had been hit with the same problem. Upon powering the unit on you get a blinking red power light in 5 successions.

I tore it down to check all the caps and narrowed it down to the power supply. The big brown (primaries?) look pretty sad from the top. I believe two are Samsung and the others are "samyoung" . Is it typical for caps this size to go bad on their own? From what I have seen the smaller caps and the two red ones pictured are the most popular for this psu.

The power supply is part number BN96-00249A. Honestly, it wouldn't sting too bad for me to drop the $200 on a refurbished PSU, but if this one isn't absolutely ravaged I would much rather repair it myself and save the dough. I've repaired a handful of automotive ECUs, so I'm fairly confident doing the work.

Thanks for giving the noob a bit of your time. I hope someone can shed some light in my situation.

[mockingbird]

Re: Akai 42" Plasma Power Supply - Photos Inside

See Bill, I told you those Akais were Samsungs inside.

[PlainBill]

Re: Akai 42" Plasma Power Supply - Photos Inside

See Bill, I told you those Akais were Samsungs inside.

Technically, they are not. The panel and associated electronics (this includes the power supply) of this set were made by Samsung. Akai came up with the rest of the electronics and the case. As an analogy would be the DeLorean. It's engine was produced by PRV (Peugeot-Renault-Volvo). Claiming it's problems were due to it's 'French engine' would ignore the true cause of it's failure.

As much as I can establish, the process goes like this: Samsung builds the plasma panel and the associated electronics (drivers, sustain boards, and controller). In cooperation with the customer they adapt the power supply to provide the proper voltages for the customer's video, audio, and control circuits. The customer manufacturers and assembles the case, then installs the panel, video, audio, and control circuits.

One critical area is the cooling. The Philips sets I have worked on do not have any cooling fans, the entire set is designed to use convection cooling. They have a lot of heat coming out the top, but the back is quite cool. It appears the Akai set overheated, possibly due to inadequate ventilation.

PlainBill

[mynamiseli]

Re: Akai 42" Plasma Power Supply - Photos Inside

It appears the Akai set overheated, possibly due to inadequate ventilation.

What would you recommend I do from here? Would you say it's likely that the heat damage spread elsewhere as well?

[Wizard]

Re: Akai 42" Plasma Power Supply - Photos Inside

power supply is really Samsung that is part of the Samsung panel as well not others.

Right now you are shooting in the dark, you need to diagnose first. And, this TV is rather old too and very inefficient, and rather very low resolution (nearly VGA). Normal for vinyl discs to cup with age on those capacitors, press down on each and feel for bloat.

Then check all fuses (cartridge and soldered in picofuse), if none is open, proceed to power up and measure voltages. If you can't find any problems, toss it.

If YSUS board has blown fuse again, send the TV to proper eviromental disposal. Of this age, is very coarse low resolution 852x480. And parts for these is very scare.

Cheers, Wizard

[Player2]

Re: Akai 42" Plasma Power Supply - Photos Inside

See Bill, I told you those Akais were Samsungs inside.

Not sure about plasmas, but Akai rear projection TVs were indeed Samsungs, all the way down to identical boards, interchangeable remotes, and even the irritating MIDI-esque tune it plays upon power up. I have swapped boards between Samsung and Akai rear pro's before, often they are identical inside save for some small difference such as a DVI input on the Samsung and not on the Akai (although the header for the DVI is still present on the Akai!)

[retiredcaps]

Re: Akai 42" Plasma Power Supply - Photos Inside

Did you try replacing or testing these 2 red caps?

From what I have seen the smaller caps and the two red ones pictured are the most popular for this psu.