what are icons on left edge and right edge of screen?

[tjcooper]

My DSO 150 appears to be working fine. What is the yellow icon on the left side of the screen? Is it the current voltage at the center of the screen? When I select V/div and then deselect it, then moving the rotary shaft will move that icon up and down. But it does not move consistently on all the voltage sensitivities. Am I doing something wrong?

On the right side of the screen is a purple icon. I think it is the trigger voltage, but I cannot set it repeatably. Is this the Trigger Set value? Can I change it around?
tjcooper