Gray Bars When I try to watch a tape, I get large gray bars located across the screen.

It sounds like you might have shorted out the display panel driver board / boards.
These boards are located at the bottom of the screen and are prone to liquid damage.
Just before this happened, did you happen to spill something on the screen or clean the screen using a spray bottle cleaner?
The only fix I know of is to replace the whole panel but it is usually just as cheap to buy a new TV.

The grey bars signal that the source image is originally in 4:3 format - if you are using a box of some kind get in its menu and change the format from there to 16:9. The black bars appear when a 16:9 image is sent to a 4:3 format in Letterbox mode - leave it like that or the Pan and Scan mode will chop the sides.

Could be you ccd, charged coupling device, eye of camera. May be pricey to repair. go to panasonic on line for quote

that kind of happened to me, except there were gray horizontal bars going across my screen. I could only see half of what I was watching. Turns out, I just kept playing the tape and they magically went away. crazy but true. Now the only thing I need help with is getting the tape in it, as the camera won't take any tapes.

Gray horizontal lines appears when video heads in camera got dirty / clogged.
Use good quality video cleaner cassette to clean video heads, problem will resolve.

I've encountered this exact problem a month ago, except cleaning the heads did not fix it. However, I was able to find an alternative solution...

After leaving my camera closed up in a drawer for a few weeks, I decided to take it out and leave it in the sun for 15 minutes, assuming that perhaps the gray bars were a result of moisture damage. The next day (Today, to be exact) I turned my camcorder on, and the gray bars have gone away from playback, as well as the reduced sound quallity it caused.

this site is BS you have to pay the fee or you will never get help do not waste your time

when you see gray bars that means that your drum is dirty use a soft head cleaning tape for 20 secs and with the posts they are visible by removing the cassette cover there is one for audio it looks like a minus sign on the post and the other is for video and it has a plus sign on top you would need to use a phillips head screw driver with the middle cut out or a pair of twezzers and when you adjust it you turn it a very very little bit to the right start with the one with the minus sign and when the problem goes away when viewing you turn it back just a hair. when you look at the posts you will see in the middle that there is a raised spot that why you would need the tool that i described.

tape path needs to be aligned.

try to clean the video head using a blank new tape just forward it 5 times as need...do not use video cassette cleaner cause it too rough for the head....check the head if there no crack on it....if nothing you find it is time to replace the to the service center...