one of the two "side" antennas depending on which antenna had been short-circuited. The contacts on the switch were set so that one antenna was shorted for the time to be considered a "Dot" by a morse operator and the other as a "Dash". The signal could be detected for some distance off the end of the runway, as much as 30 km. The Lorenz obtained a sharper beam than could be created by an aerial array by having two lobes of signal. A pilot approaching the runway would tune his radio to the broadcast frequency and listen for the signal. If he heard a series of dots, he knew he was off the runway centerline to the left (the dot-sector) and had to turn to the right to line up with the runway. If he was to the right, he would hear a series of dashes instead (the dash-sector), and turned left. The key to the operation of the system was an area in the middle where the two signals overlapped. The dots of the one signal "filled in" the dashes of the other, resulting in a steady tone known as the equi-signal. By adjusting his path until he heard the equi-signal, the pilot could align his aircraft with the runway for landing. Two small marker beacons were also used: one 300 m off the end of runway, the HEZ (Haupteinflugzeichen), and another 3 km away, the VEZ (Voreinflugzeichen), both were broadcast on 38 MHz and modulated at 1700 and 700 Hz, respectively. These signals were broadcast directly upward, and would be heard briefly as the aircraft flew over them. To approach the runway, the pilot would fly to a published altitude and then use the main directional signals to line up with the runway and started flying toward it. When he flew over the , he would start descending on a standard glide slope, continuing to land or abort at the , depending on whether or not he could see the runway. Lorenz could fly a plane down a straight line with relatively high accuracy, enough so that the aircraft could then find the runway visually in all but the worst conditions. However, it required fairly constant monitoring of the radio by the pilot, who would often also be tasked with talking to the local control tower. In order to ease the workload, Lorenz later introduced a cockpit