Having an image on your TV screen that doesn't fill the screen is frustrating. On a Proscan TV, this problem can result from issues with a source signal, external device, the TV's settings and issues with a connected PC. Troubleshoot the causes of the problem to narrow your issue down and see if it's something you can correct on your own.
If the Proscan TV is set to the Normal aspect ratio and the source's signal is smaller than the TV's native resolution, the image on the screen will not take up your TV's entire screen. You can switch to a different aspect ratio, such as Zoom, Wide or Cinema, which will stretch the picture to fill the screen, however, the picture may then become pixelated.
The source of the signal you are pulling in over the air may be broadcasting a show in a smaller resolution than normal. This could be an accident on the part of the station sending the feed or it could be on purpose. Your only options as a viewer after attempting someone at the station sending out the signal is to adjust your TV's aspect ratio to make the picture larger, but again, the pixelation as a result of stretching the image out may not be worth having the image fill the screen.
If you have a PC connected to your Proscan TV, the PC's display may not fill the screen if it's set to a resolution that's supported by the TV. The resulting PC display on the screen may not fill the screen, vibrate or be distorted in some other way. Check your TV's manual for a list of supported PC resolutions. You can change your PC resolution through the Display part of the Control Panel.
The output settings on a connected external device can also affect how a display fits your Proscan TV screen. Access the settings on the external device and check that the video output settings are compatible with your Proscan TV. For example, if you're external device is outputting in 1080i and your Proscan TV doesn't support that resolution, the image may be distorted in some way on the screen, such as not filling it. Also, if your external device has its own set of aspect ratio controls, flip through the available aspect ratios to see if the aspect ratio the device is currently set to is just not ideal for your TV.