Top 20 Akai PT4298HD Rear Projection Television - Page 4 Questions & Answers

I think it does,most all hdtvs have them.

Ur high voltage have prob,it ur FBT the big block of plastic red wire solder to the deflection board.

You put the lens or tube on backawards...

Downtown off sixth street. Just kidding. This set has an a/c power supply located outside the wooden frame that secures the main and deflection circuit boards. Very seldom does this cause a problem though. The most common problem in my experience is convergence failure. Testing this is easy. The convergence board is seperate and is mounted above the others. Small pcb with large heatsink. Removing the blue wires with the red plug(I think it's a 5 pin plug) should restore power if set is in shutdown due to that failure. Then you can just try to replace that board if avail. Next problem on this set is coolant can start leaking from the tubes and go onto the circuit boards. Use a bright light and a good pair of eyes to examine the board closely, looking beneath the picture tubes for moisture or drops or corrosion on boards. Please make sure tv is disconnected from power source while testing and good luck, Russmann.

Yes! an idea that the flyback transformer is shot!


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Look at AC power supply board they are bad about poor solder joints resolder thyrisitor on board.

It's only a problem when you try and finance a new bulb ($400.00 for mine). But seriously, the only "problem" is that an older bulb exhibits much lower light levels and the picture has crappy color, brightness and contrast. Keep a coffe can around and put a few bucks in it everytime you watch it. when the bulb finally blows you'll have a couple hundred bucks in there towards a new one. (a little easier to handle)

Packman

GO THROUGH TRACING THE MAIN CORD, IT WILL LEAD YOU TO MAIN BOARD, MOST PROJECTION TV HAVE 2 OR MORE BOARDS.....IF YOU ARE ABLE TO SEE BIG CAPACITORS HAVING 400V OR MORE VALUE, THATS THE ONE..CHECK OUT..

These sets need to have all three colors - RED - BLUE - GREEN - lined up correctly on the screen in order for the picture to look normal. This is called convergence.

When its out of alignment the video will look 3-D, wavy, distorted, etc. Most of the time you just need to adjust your convergence in the menu. If you cannot adjust it in the menu - then your convergence is broken and needs to be repaired. Convergence problems are very common on all Projection TV sets including Sony, Samsung,JVC,Philip Magnavox,Panasonic,Akai,Pioneer, Hitachi,Mitsubishi,Zenith and others.
You can get more information and a DIY convergenece repair kit with instructions from the link below.

Here are some of the most common problems with these sets...

Problem #1) Convergence

Yours may have one or more of the following symptoms...

*Screen Looks 3-D
*Colors wont align
*Screen may look distorted or warped
*No Audio/Video - TV Shuts down - May also make a constant chirping sound

Problem #2 - Another common problem is dull or washed out video.

Your set may have one or more of the following symptoms....

*Dull looking picture
*White looking picture
*Halos around objects
*Red/Orange looking picture

You can see some more examples and find a fix using this link on Fixya http://www.fixya.com/support/r2861467-solution_video_looking_whiteish_dull

First, You cannot resync the remote, Second the IR sensor may be bad on the tv and third, the Digital bd may be bad. The IR sensor connects directly to the Digital bd which is the brains of the tv. Also, there maybe a stuck button on the remote or the buttons on the tv.

Do not panic! Do not throw your TV away like I wanted to! Here is what may be the solution for most of the members who have posted their complaints here recently. I am not an expert, but I followed all blogs from various websites and forums, and the conclusion was the same;replace the convergence board for this model. I purchased it from www.partstore.com and since this Akai is the same model asa comparable Samsung Model, buy the Samsung comparable Convergence board for $77. It came to about $85 after shipping. Call them if you need the exact model #. The Convergence board has two black STK ICs and two colors of wires, a gray kind and a blue kind,all which have 'pins' and can easily be unplugged from the circuit board in the TV. It is basically a complete system that takes less than 30 minutes to install. It is a simple swap procedure, with no soldering.You only need the new board and a screwdriver! Remove the lower backboard of your TV where the cables are plugged in (do not unscrew all the screws for the screen, as it is unnecessary, and might just damage your screen if you are not careful.) It has a u-like shape and comes off easy.Detach the gray wires connecting your old board to the rest of the circuitry, and detach the blue wires connecting the old board to the circuitry. On the old board, there are connectors marked,from left,blue, green and red. Detach those from the old board, and mark the wires so that you may connect the correct the wires to the new board. You then unscrew the only screw connecting the board to the TV,and unhook the board from the TV. Hook the new board to the hooks which held the old board, and screw the lone screw to the board. Plug the gray cables from the new board to the connectors where the gray cables from the old board were,and do so for the blue cables. Connect the multicolored cables to the blue, green and red, just as was done on the old board. Reattach the cover and test the TV. Please do not replace the two STK ICs only. When I removed my old board, I realized that there was a burn mark, where the ICs were, but maybe it was a fuse.You may replace the ICs only to discover that it was another problem.Good luck, and I wish you all the best in the repairs. I just saved about$100 for a repairman just to show up.

Call Encompass for Parts same as samsung cheaper just to replace boards 1-800-638-3328 power supply board will have number on it.

Hi,

It still can be fix, the unit need an immediate repair, a problem on the video output module has something to do with this, a burnt resistor or capacitor has to be replaced.

Hope this info helps

This is a comon problem
There are two large convergance chip's
the are failing .Replaceing them will
corect the problem . The chip range
in cost from 16,00-30.00 .There cheap,
so dont let the shop over charge you
for parts when and if you decide to
repair it.

The problem is that the convergence board needs to be rebuilt. The board is located up and to the left looking in the back of the unit. It has two large Sanyo stk392-040 amps mounted to it and a grouping of 3.9 ohm 1/2w fp resistors in the yoke return circuit out in front of the amps. It's likely one or more of these will also need to be replaced.
If you're going to attempt this yourself you need to be VERY good at soldering and desoldering and toy should have a good VU meter to check the resistance and tolerance of the components out in front of those amps... Also think about adding a fan to the face of that board with a 9v regulator operating off the 20v +/- line feed. This will substantially keep the amps cooler and less likely to short out again.
If you would like to justa have this done our shop rebuilds these units for $225.00 dollars which includes shipping back to you...
Hope this helps!
Bill

William Rayburn, CET
Premium Technologies
PO Box 442
Long Beach, WA. 98631
360-642-4993

The most likely cause is shorted convergence chips and possibly a few pico fuses.

These sets need to have all three colors - RED - BLUE - GREEN - lined up correctly on the screen in order for the picture to look normal. This is called convergence.

When its out of alignment the video will look 3-D, wavy, distorted, etc. Most of the time you just need to adjust your convergence in the menu. If you cannot adjust it in the menu - then your convergence is broken and needs to be repaired. Convergence problems are very common on all Projection TV sets including Sony,Samsung,JVC,Philip Magnavox,Panasonic,Akai,Pioneer Hitachi,Mitsubishi,Zenith and others.
You can get a convergenece repair kit with instructions from the links below.

Here are some of the most common problems with these sets...

Problem #1) Convergence

Yours may have one or more of the following symptoms...

*Screen Looks 3-D
*Colors wont align
*Screen may look distorted or warped
*No Audio/Video - TV Shuts down - May also make a constant chirping sound

Problem #2
Another common problem is dull or washed out video.

Your set may have one or more of the following symptoms....

*Dull looking picture
*White looking picture
*Halos around objects
*Red/Orange looking picture

You can see some more examples and find a fix here http://www.fixya.com/support/r2861467-solution_video_looking_whiteish_dull

You have a convergence board out of adjustment or faulty the best way to tell this is to have a estimate done on it but I can tell you its a convergence issue that is not fix can get worse over time.

This is nothing we can fix over email but we can give you paid advice and that is have it looked at locally as this is a complex issue that cannot be fixed over a email system.

Please do click the ACCEPT BUTTON to accept my advice.


Thanks
Rulds2008
Expert Tv repair Guru Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/edwy_1a56970cf1ea4620

I would have a service company look at it ASAP. That type of problem can cause extensive damage to the High Votage panel. Do not play it !

if the picture looks kinda 3-D
Normal 0 MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} The best advice I can tell you at this point is to go to tvrepairkits.com and order the complete convergence kit for your model of TV set, no need to search and order multiple parts from different sources and pay multiple shipping fees! The kit comes with original Sanyo STK IC’S , not those cheap aftermarket or china made IC’S full pictorial directions, the thermal paste, resistors, the correct Pico fuses, AND free live on-Line tech assistance in case you run into a problem with the repair. They ship out 2 to 3 day Priority mail, the next day in most cases you may need to open the set and tell them what the STK numbers are on the chipsGOOD LUCK!!!
Larry Dillon, senior tech/tvrepairkits.com

Hello!
If you haven't replaced the lamp before, it's better if you do, if you already replaced it and this issues are still there, it's a possibility that your ballast might be defective, maybe it doesn't have enough voltage to light up the lamp