Hitachi 51F500 (Two separate problems?)

It depends on the TV but for Hitachi I think it is on the DMD board. To keep the settings when unplugged.

Use an external directional microphone with a rubber shock mount. You can get them cheap on Ebay

Feedback is a sharp, loud noise that can come through the earphones of a headset unexpectedly---it occurs when the headset is getting sound (feed) from someone else speaking or playing music into a microphone. This sound can create a dangerous situation for someone who is operating expensive equipment or flying a plane at the time since it can disable hearing temporarily.
If you experience feedback often, it could also lead to serious hearing problems.

Mic Too Close to the Speaker or Volume Too High
The main cause of a feedback sound in a headset is proximity to a speaker. If a person holding a microphone on the other end gets too close to a speaker, it creates a loop of re-amplified sound that results in the loud, screeching noise. When the volume on the other party's microphone is too high, it is more vulnerable to picking up unwanted noise and feedback from speakers and sound output devices in the room. So make sure that you ask the other party to turn down the microphone to a normal level and stay far from speakers. b> Two Microphones Gathering Same Sound b> When the other party places two microphones too close to each other, it could cause feedback. When positioned toward the sound source (such as a person speaking) the microphones will both pick up the same audio and compete with each other when creating the output of sound, causing a sharp noise in your headset. This problem, called acoustic phase interference, is resolved by simply ensuring that the other party uses one microphone at a time. Poor-Quality Headset or Microphone b> One common cause of feedback is simply a poor-quality headset or microphone. Most modern headsets and microphones have noise-canceling features that manage and kill feedback before it has a chance to occur. These noise-canceling headsets are essential for pilots and aviation crew members. If you hear sudden feedback that is strong enough to hurt your ears, the headset or microphone is simply not properly equipped to actively cancel that unwanted noise before it hits your ears. Buy a higher-quality noise-canceling headset to manage the feedback noise when you're going about your tasks. Hope this helps.

Burning smell usually signals that a part burned. This is a major malfunction, the power source of the tv was literally fried. Replacing it will be quite expensive - around $250 - and definitely a job for a pro - who know what else was damaged in there, the tv must be tested by someone who knows this very well.

the only way to fix this problem is by replasing the convergence ic

convergence problem, contact a servicer, avg repair cost for this is 250-400

If you go into the customer menu and select convergence and red or blue are skewed and will not adjust---you have a convergence circuit problem.

51f500 uses two of the STK-392-110 OR STK-392-150 convergence IC chips. Both are the same but the 150 chip is a longer lasting part than the 110 chip. Both chips and any bad protect resistors around them need to be replaced and the set adjusted with the Hitachi remote.

Most of the time just both chips need to be replaced and the set adjusted.

Considering you can buy all the parts needed for under 30 dollars on Ebay if you or someone you know can do this repair you can save a lot of money--most shops are going to get 300 or more. I can give you general instructions and tell you the best seller to get the chips from on Ebay---I buy the ones I use there.

Let me know if you have questions or need advice-I am here to help people.

If this information has helped you rate this solution as I do this here FOR FREE.

SD TECH.

I had the same problem Replace the IC's and it should fix this

The problem is an assembly called the "Flex Converter". This is not available from Hitachi, even though the set is relatively new. The converter must be removed from the set and sent out to Hitachi for repair.

Most likely bad convergence IC's! Location numbers should be IK04 and IK05. Generic numbers STK392-110.