The 430 had two beams, a co-secant squared beam for surveillance, which wasn’t desperately good, and a pencil beam for the talk downs. You had a radar head tilt switch and you needed to get the beam up high during the approach to see the blip through the returns of the ridge 1.5nm from touchdown then quickly down to retain radar contact until termination at 0.5nm.
The radar head had two rotation speeds, 20 and 40 rpm although we never used it had 40rpm as we always thought the radar head would fall of its perch. The rotation switch had three positions up 20, down 40 and centre OFF and the switch was next to the radar head tilt switch.
I had the habit of resting the ball of my thumb on a ridge of metal on the centre console so I could operate the radar tilt switch with a finger. On one occasion the ball of my thumb caught the rotation switched and turned it off!! Radar service was terminated! Everyone go around.
Even banging the rotation immediately on again still required the picture to align which took several minutes, even with the first align button subsequently installed.
Happy days!