Can't clear channel off screen of Sony Trinitron...

I have an older Sony 27" Trinitron TV (KV-27EXR25) that I use in my spare bedroom. I lost the remote some time ago, but the picture is still good and would like to continue using the TV. My problem is I can't clear the channel number off the screen. I had lost the remote some time ago and use the remote from my cable provider. Unfortunately the remote for my cable does not clear the channel number from the corner of the screen. What I mean by channel number, I am referring to when you hit a button on a TV remote to get the time, channel, etc from the television's built in menu. That's the one that stays on the screen. I used one other universal remote, but that didn't work either. The TV has not been used in a while so I guess when it was used last with the original remote the channel number was put on the screen. Any help would be appreciated. Thanks SD