Anyone had experience with rear projection HDTV repair?

[Queasy]

My 48" JVC rear projection HDTV that I purchased almost 9 years ago decided to develop vertical lines across the screen. If we leave the TV off for a while and turn it on, the lines take about 5 minutes to appear. I opened up the back and cleaned out all the dust but it still occurs. Some googling suggests that one of the chips is malfunctioning and needs to be replaced. However, this sounds like an expensive proposition for an older set. I'm going to call a local shop that repairs JVC HDTVs tomorrow but was wondering if anyone experienced anything similar so I can get an idea of what to expect when I call.

My other option is this 40" Samsung LCD HDTV using 20% Bing cashback. I'm on a tight budget for repair/replacement.

 

[88MVP]

I did a little googling the other week for a Sony Rear Projection TV that was developing green lines across the screen horizontally. Not sure if this is the same problem your tv is having, but this link was helpful and the same procedure apparently works for most brands of RPTV. I gave the adjustment screw a slight tweak to change the voltage and viola - no more lines.

http://www.somelifeblog.com/2007/06/sony-projection-tv-red-line-repair.html

Hope that helps

 

[Krakn3Dfx]

I spent the better part of a Saturday replacing the convergence chips in my 57" Hitachi...only to find out it was a single 20ohm resistor that was actually the problem. I wasn't too upset about it tho since replacing the convergence chips in an almost 8 year old TV was probably a good idea anyway, and I honestly think the image quality improved from before the problem started, although my wife didn't see a different.

If you're good at soldering (I'm not, hence the entire day on it) it probably won't take a lot of time to replace the chips if that's the problem. If you decide to pay someone to do it, you might be better off checking out the Dell.com 60" Mitsubishi for $650 after Bing Cashback in the Hot Deals forum. Even tho I just did this repair earlier this year and everything has been fine, I went ahead and order a Mits from Dell since after almost 8 years I figured it was time to enjoy some newer home theater tech .

Good luck.

 

[PM650]

Could you possibly post a pic of the screen? It's quite possible that the convergence chips are on their way out; my experience is that they generally run very warm. Some of the projection sets I've replaced chips on have them right in front - on a board accessible by removing the speaker panel. If this is the case with your tv, you can try chilling the heatsinks a bit with an upside-down can of compressed air. If this affects the lines, you may have found the problem.

 

[Queasy]

Called a local repair shop and the ball park figure they gave me was $500.

I do think it is heat related with the chips though as there are no lines when the TV is first turned on after being off for a good while. As soon as it "warms up" though the lines appear.

The 60" Mitsubishi DLP set is very temptiing but is just out of my price range. Money is tight because of no bonus this year and Christmas with two kids is right around the corner.

 

[Modelworks]

Consider putting a fan blowing over the heat sinks. It may give you a few more months usage. They really under design the heat sinks in tv. A pc fan can be used with a plug in wall adapter for power.

 

[slag]

yeah, convergence chips or bad caps.. maybe if you just open it up something will be obvious and it will be a cheap fix

 

[alfa147x]

I change out the convergence chips in our Sony about every 6 months 2x $5 ebay or mats electronics... i should install a slot loader for it, but i have it down to 30 mins of work now

 

[Queasy]

I change out the convergence chips in our Sony about every 6 months 2x $5 ebay or mats electronics... i should install a slot loader for it, but i have it down to 30 mins of work now

I'm tempted to do this just to save some money but I've never done any soldering in my life. I also can't find any cheap replacement parts. Nothing in the $5 range at least. $60-$70 or more.

Here's what my TV looks like btw

Anyone know how to get a JVC AV-48WP30 service manual for free?

 

[nsafreak]

Yep that's a convergence issue alright. You can purchase kits that'll come with all of the parts needed to fix the convergence issue for $72. If it's just the resistor you can get those at a local electronics store a lot cheaper. Your other option as stated for a temporary fix is to cool off those parts somehow.

 

[Krakn3Dfx]

Convergence.

Have a buddy that might have more soldering experience? If not, you just need to be really careful and take your time. I'll see if I can dig up a manual for you, I'll PM you if I can find one.

UPDATE: Couldn't find the manual, but I did dig up the site I ordered my repair kit for my Hitachi 57F500 from. They also have a repair kit for yours here: http://www.tvrepairkits.com/component/content/article/164

They include everything you need except for the solder and the iron, and do a good job of walking you through step-by-step, I highly recommend them. Like I said, it took me most of a Saturday to get it done, and make sure your TV is unplugged for at least 3 days before you go rooting around in it unsoldering and re-soldering chips.

Hopefully this helps. I would definitely recommend checking with friends and seeing if anyone you know has some soldering experience, but even if you have to do it yourself, it's more of a matter of patience and paying attention than actual skill. Also, I found that having soldering and de-soldering braid makes things a lot easier than just using the soldering wire. I spent less than $20 on the soldering iron and braids at Radio Shack, so if you don't have that stuff, expect it to add about that much more to the price of repair.

Good luck dude, hope it works out.

 

[Krakn3Dfx]

Also, before you do anything, you might pop off the back of your TV and look at all of the resistors for any discoloration. If I had done that ahead of time, I could have avoided replacing the convergence chips altogether in favor of a 20 cent resistor that took about 20 minutes to replace after a full day of convergence chip replacement. The resistor in my case was clearly discolored, I just never thought to look for it ahead of time. I'm glad I did all of it, it was a good learning experience, but if you can just replace a resistor, no reason to do everything else.

Also, if it's not happening until it warms up, check the thermal paste situation between the convergence chips and the heatsink they rest up against. It might just be a crusted thermal paste crack that you can fix by applying a fresh coat of thermal paste. You can likely do that with no soldering at all.

 

[PM650]

I change out the convergence chips in our Sony about every 6 months 2x $5 ebay or mats electronics... i should install a slot loader for it, but i have it down to 30 mins of work now

I suspect you're doing a good job of supporting the chinese counterfeit semiconductor industry :awe:


The AV-48WP30 uses STK392-110 convergence chips, which is quite common. These can be replaced directly, or can be upgraded to STK392-150, which supposedly run cooler (same pinout, no changes needed). Just be sure to get genuine sanyo parts, the last tv I replaced these on had warranty work done on it and the failed STK392-110 was a fake/counterfeit replacement. Two STK392-150s will only run you $26 (see below).

Whenever this guy has what I need, be it sankens, toshiba or sanyo, I order from him: http://www.acme-sales.net/portal.php?product=!&country=USA 100% genuine parts. He also carries flameproof resistors for convergence circuitry, just replace as necessary with these (measure each to make sure).

As far as replacement, you can easily snip off the old chips from the top and desolder the pins individually - shouldn't be too difficult for a first time job.

 

[Muadib]

I found a link to the pages you need: http://home.comcast.net/~dande76530/Convergence.html The parts that need replacing appear to be in the front, not the back of the set. Perhaps the 2 guys that have done the repair can take a look, and verify, as I ain't no repairman.

 

[Queasy]

Thanks for the help. Without the diagram I wouldn't know which chip was which. I popped off the back of my TV to take a look and clean out all the dust but apparently the convergence chips are actually just inside the front panel.

Hopefully, it is nothing more than just replacing the thermal paste. I can do that easy since I've done it with CPUs before.

 

[Krakn3Dfx]

Thanks for the help. Without the diagram I wouldn't know which chip was which. I popped off the back of my TV to take a look and clean out all the dust but apparently the convergence chips are actually just inside the front panel.

Hopefully, it is nothing more than just replacing the thermal paste. I can do that easy since I've done it with CPUs before.

Looks like you might be able to get the diagram here:

http://www.nodevice.com/manual/newmans/AV-48WP30-schpdf/get17047.html

It's like $8 for a 24 hours membership, but you should be able to pull a PDF with the service manual. Still no luck in getting it for free tho.

Also, this guy has a blog where he goes through step-by-step on his repairs:

http://cmpalmer.blogspot.com/2006/11/fixing-my-own-tv-part-ii.html

he doesn't have the same model, but other than location of chips, the method is pretty much standard on all of them (pretty easy to tell where the convergence chips are, they're always stuck to a giant heatsink). Someone in the comments even mentioned using his blog for repairing their own AV-48WP30.

 

[Queasy]

How funny. Today I got a surprise bonus from my company. Nobody expected it because they actually suspended bonuses and merit increases for this year and they actually managed to keep it a secret. Of course, this would happen right after that deal for the 60" Mitsubishi DLP goes dead.

I think I still may try to fix my JVC TV though. If nothing else I can learn to solder and it can be an extra TV in the house or I can resell it

 

[PM650]

How funny. Today I got a surprise bonus from my company. Nobody expected it because they actually suspended bonuses and merit increases for this year and they actually managed to keep it a secret. Of course, this would happen right after that deal for the 60" Mitsubishi DLP goes dead.

I think I still may try to fix my JVC TV though. If nothing else I can learn to solder and it can be an extra TV in the house or I can resell it

:thumbsup: No sense in tossing an otherwise good tv (we hope) when you can learn something when fixing it. I'm always baffled by people who suddenly think something is worthless because a few components need to be replaced....it's just too bad the same mentality doesn't exist with used cars :\

 

[Slacker]

where are you located?

I have a 48" iArt Pro with a bad red gun, would sell it cheap.