Periodic "Dimming" Issue on JVC 56FH97? (1 Viewer)

[BarryNS]

I bought a JVC 56FH97 set new a few years ago, and used it with HDMI connected HD satellite and a component cable connected progressive scan DVD player. I initially calibrated the set with the user menu settings using some settings I found online, properly disabling all the "smart picture" and auto adjust features of the set, and also ran a THX test segment on one of my DVDs. Not long after a software update was applied to my sat receiver, I would occasionally notice a sudden "dimming" of the screen while watching sat (either SD or HD channels) - as if the brightness or contrast had suddenly been dropped 3 or 4 levels. This would typically keep repeating every 4 or 5 minutes, although there was no noticeable corresponding sudden "jump back" to the normal brightness levels - it apparently gradually came back, since I'd notice a sudden dimming again every few minutes. I never noticed any brightness shifts at all with DVD's however. Some days it would be fine - even for several weeks or months of TV viewing - then other days the set would do it for as long as I had the TV on and powering it off and back on, unplugging, time of day, etc made no difference. I chalked this up to something wonky with the sat receiver since it seemed to occur only after the s/ware update was applied.

Fast forward to this past Christmas and I now have a PS3 connected on the second HDMI input -I recalibrated with the bluray version of DVE, and not surprising I did lose some brightness with age of the original lamp, but I am still not even at the "zero" brightness setting yet. However I am seeing the same occasional sudden "dimming" repeating with the display - I don't have any more SD sources connected so I can't say for sure if it is still just on the HDMI inputs that this happening.

Is this a problem with the set, or could this be an AC power conditioning issue? The TV is plugged directly into the wall outlet, no heavy appliances at all in my apartment, and the set has never been exposed to sudden outages, etc and I always make sure to unplug when any electrical storms are forecast.

I am suspicious of the power service in my building (apartment complex) as I've had strange things happen like building power outages affecting only some outlets in my unit, a few months of unexplained suddenly much higher electric consumption billing with no new appliances, etc - so I would not be surprised if some other units or machinery are powered off my service to be honest.

 

[Gregg Loewen]

most likely the bulb

 

[BarryNS]

Thanks Gregg - sheesh, that's good in a way I suppose (not a light engine or set power supply issue) but not so good also, since it started doing this within only a few months of purchase (maybe 6 months tops) after the software update on my sat receiver, and the set was only ever used with the calibrated settings - I never abused the brightness/contrast, etc.

Other than this I couldn't be happier with the set though - it does have a bit of silk screen effect I can see, but so long as I am actually "absorbed" by whatever I am watching I don't even notice it.