View Full Version : Picture anomaly question for the TV Experts
tentoze 01-29-2009, 08:42 AM Within the last week or so, my trusty old JVC 32" CRT tv has developed a problem. The top 2" or so of the image are garbled, and actually invert the image on screen. I've tried to capture the phenomenon in the attached crummy pic, where the letters on the right are upside down and backward. Does anyone know if this is something that can be fixed by a service guy, or is it a symptom of the thing being on its last legs? Any advice is appreciated.
kx250rider 01-29-2009, 10:30 AM That's a classic vertical problem ("Foldover"). It's caused 99% of the time by a dried out electrolytic cap. Does it get better/worse as the set warms up? If so, the offending cap is usually easy to spot with a can of freeze spray. Otherwise, another method is to measure all the electrolytics in the vertical circuit with an ESR meter, or the old-fashioned way; scope it.
I don't ever speak for other techs' fees, but this job should be in the lowest category...
Charles
radiotvnut 01-29-2009, 11:20 AM Yep, likely bad caps in the vertical circuit. If you don't have the equipment to check them; just replace them all (probably not over a half dozen). The caps will be located close to the vertical output IC. The IC is a stand up device mounted on a heatsink. In some cases, bad caps can take out the vertical IC; so, I'd go ahead and start replacing caps before they take out the IC. If the IC goes, you'll just see a straight line across the center of the screen.
tentoze 01-29-2009, 11:23 AM Thanks for the input, guys. I'm no tech, and no way I'd go inside this thing myself- but at least I think I know now that it should be repairable for a reasonable cost.
zenith2134 01-29-2009, 02:39 PM Had a JVC AV-2672S from 1992 with the foldover problem. I didn't know how to diagnose and fix sets yet so it went to the shop. 75 bucks for a replacement of the IC, associated electrolytics, and labor. Worked like a champ for years til I gave it away. Good luck.
centralflori 01-29-2009, 04:53 PM I think we may have that same tv. What is that model number?
tentoze 01-29-2009, 05:03 PM Av-32920.
centralflori 01-29-2009, 05:12 PM Same model! Do you have a digital converter box hooked up?
tentoze 01-29-2009, 05:13 PM No, I'm a Luddite.
centralflori 01-29-2009, 05:20 PM Don't know if it has anything to do with having the digital box hooked up, but I can set mine on wide screen and not see that top couple of inches. Reason I got the converters is where I am at I would see nothing but snow without them. With them it's like having satelite without all those pesky channel choices to make. You know like ESPN or HBO or music channels. Using the converter boxes all the regular local channels have multiple channels that I did not know existed even with satelite. Of course if you have satelite or cable the point is moot.
MRX37 01-29-2009, 06:54 PM Yeah I'm going to also say a bad cap or two. Easy fix really. Here's some signs that will let you know when that TV is on its last legs:
The picture becomes dim and tinted, even with the brightness and contrast at max.
The picture is still tinted even with the color turned all the way down.
You see smearing (color bleeding) to the right of bright colored objects, especally bright yellow, red, and orange objects.
Any or all of those signs usually mean that the CRT is dying, and when that goes, nowadays it makes the TV worthless. From your pic though, the picture looks bright, seems to have good focus, and I don't see color bleeding. Get those caps changed and it'll probably give you another good 5-10 years, maybe longer.
tentoze 01-30-2009, 12:42 PM Just went by a repair shop local to me (very local, actually, only about 1.5 miles away, been in business since 1946), described the problem and the estimate to fix is $150-175. Sounds a heck of a lot better to me right now than $1500 or more for a new whizbang flat-screen. Now to coerce my son to come over to help me load this beast in the truck...
centralflori 01-30-2009, 03:59 PM If you like the crt better thats great, but if you shop around you can get one of those flat panels for a whole lot less than $1500.
http://www.costco.com/Common/Category.aspx?whse=BC&Ne=5000000&eCat=BC|79|43064&N=4018654+5000014&Nr=P_CatalogName:BC&Ns=P_Price|1||P_SignDesc1&lang=en-US&topnav=
BTW there are many fine merchants on the web as well as brick and mortar, and I don't have any affiliation with this one, other than I buy crap there.
PS. Hope I didn't screwup your thread and make it a question of value.:D
freakaftr8 01-30-2009, 04:49 PM Yeah, look around, less than 150 will get you a nice working set! CRT sets seem to be falling out of trees here lately.. I just got an old 1988 Sony 27" with remote and matching stand for 20 bucks yesterday and it just needed a bias dreive and focus adjustment. Looks excellent for a 21 year old set! I have seen HD Plasma sets around here for 500. Although I wouldn't own one as plasma seems to be becoming archaic technology after the introduction to OLED technology..
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