When I turn on the TV, the led blinks and I have the audio, but the picture does not appear until some time. First 15 minutes, then worsened to nearly 1 hour. Some forums attribute this problem to dirt, so I opened up the set and did a bit of cleaning, but I had not any luck. I did not disconnect the flyback to clean the connection to the tube because I was not sure how to discharge it first. Is this related to dirt, or do I have to change the flyback? Is this problem caused by something else that I ignore??
Thanks for your help in advance!!!

fernand, October 2012

First, the model number you supplied, KV-34XTR10, is not a 50 inch set but a 43 inch tube set.

Secondly, the symptoms you relate of have audio but no video - or that it comes on late, and gets longer as time goes by, is related most often to failure of the high voltage system. The repair nearly always revolves around the flyback transformer and/or the horizontal deflection amplifier (the horizontal output transistor, for example).

The best repair method is to replace both the flyback and the horizontal output transistor because if only one is replaced it is common for the other to fail soon thereafter.
If you need a tech , here you are a link of a tech website www.tvrepairjacksonvillefl.com

henry, October 2012