Clutter control also affects past targets. Try to adjust the sounder’s picture solely with the main gain control, and when you start to see clutter, back off the gain a little. Try this the next time out: Turn up the gain until you start to see clutter on the screen, and then increase it a half-point higher. At this point, you should start seeing a lot of blue speckles. Now, increase the clutter level until these blue speckles disappear.