"In DGFT mode with HOB missiles equipped and the default settings, holding the 'Radar Cursor/Enable Switch' will slave the HOB seeker to your HMCS so you can point at off-bore targets with your head and fire, without having to go in and change slave modes just for that - it's a nice temporary switch, after which the seeker goes back to being slaved to radar lock"
Holding TMS UP does this by making the ellipse appear. Is using the 'Radar Cursor/Enable Switch' different?