You might want to try search though,its awesome on this scanner
it has a public safety and each button is a frequency range ,the 197 quickly picks up digital and decodes it by itself unlike my uniden 996xt.This is a great scanner,just remember everything is treated as an object and you are good.When you search you can store the channel you found even if its trunked and it ends up in your scan list 01 (which you can rename later if you want).
Sc is usually 800mhz.
The signal stalker is if you have the scanner mobile and you want to see whats transmitting around your car or nearby area.
i'm not sure the "close" but I have to bet it depends on your antenna strength.
I for one appreciate the OP of this question because being new to the hobby this thread found by "search" helped answer my question exactly. The difference between the two signal stalker and limit search