I had a popping sound coming from the tv and now I have no picture and no sound.

When troubleshooting these units, there are always several variables to consider. First check to see what last occurred with the unit such as did the children play video games, did the electricity go out due to bad weather. You may see that there are many possibilities but let's focus on what occurred last to the unit. Once we determine what happened last, we may isolate the actual cause of the problem. The actual cause may be associated with projection issues, older versions (Picture tube), interference from devices located nearby, and even a radio turned on and located really close to your unit. This is normally known as electromagnetic interference to electronics and is very common with the error you have provided today. Please continue to look for anything EXTERNAL to the unit before looking at the internal components. I have been working on these a long time so feel free to follow up with me.