Question about Sony FD Trinitron WEGA KV-27FS100 27" TV
In the power supply and in the horizontal output areas there are some inductors (chokes) and some high frequency transformers. These are wound with enamel wires on a form which is mounted on a solid ferite core. The windings are normaly soaked in a special laquor and baked during the manufacture process to try to not have any loose windings or any loose mechanical fits.
When the transformer or inductor units are in the circuits, they are working with very high frequencies, and with very intense modulation or signal levels through them. It is possible that if there is any loseness in their assembly, they will start to ring or sing by going in to a mechanical resonation. This resonation is produced from their internal high frequency magnetic field. The frequencies are far beyond the fundemental human hearing range, but the sub-harmonics are not. The driving waveforms are mostly sawtooth or square waves in their properties. These allow for a substantial amount of complex harmonics through any resonant device that they can pass through.
It is possible to fix this, but it will take a lot of time. The first thing is to find the inductor that is resonating. The more complicated part is to see if it can be stopped from mechnaicaly resonating without damaging it, or causing problems with its performance.
Sometimes I have found a resonating inductor, and was able to fix the resonation by using a simple piece of thin plastic between its winding form and the iron core that it was wound on. I had others were I re-painted them with a high voltage rated laquor and then let it dry. I also had some that I was not able to get easy access to fix them for this. The only choice was to order a new transformer if the problem was to be fixed. And, there is no guarantee that it would be fixed if the new one had the same fault.
Posted on Apr 13, 2008
Tips for a great answer:
Sep 09, 2010 | Sansui 27" TV
Feb 05, 2009 | GE Standard (CRT) Televisions
Nov 08, 2007 | Samsung SlimFit TX-S2783 TV
Jun 13, 2007 | Samsung TXJ2879 28" TV
May 22, 2007 | LG 30FZ4D TV
Feb 25, 2007 | Samsung TXN3071WHF 30" TV
83 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: