The first clip simulated an aircraft flying into the beam. It enters to the left of the beam, into the dot-zone. You can see that the instrument is pulsing left with the dots. Also note that a strengthening of signal makes the instrument point left. It was important for the pilot to distinguish between the pulses and the more gradual swings of the needle due to changing signal strength:
https://youtu.be/vfSkcZVFe3o
The second clip simulates the aircraft starting on the left of the beam in the dot-zone and flying starboard into the dash-zone.
These first two clips do not only simulate a blind landing approach, but do also simulate the "Knickebein" beam guidance system used in early 1940 at the start of the Battle of Britain. At that time the earlier Ebl.1 receiver would still have been fitted to the German bomber aircraft:
https://youtu.be/guUifTlZcoE
Clip three simulates the "Vor-Einflugzeichen" (VEZ) or first approach beacon. The VEZ was located 3000 meters before the runway. This is a slow pulse, low tone signal. The pilot would approach on a constant height and on hearing the VEZ would start a given descent. Keeping one eye on the variometer and the other on the AFN he would be near the ideal glide path onto the runway
https://youtu.be/YnYwdweLMOM
Clip four simulates the "Haupt-Einflugzeichen (HEZ) or main approach beacon. The HEZ was located 300 meters before the runway. This was a fast pulse, high tone signal; the HEZ is an urgent warning that the pilot does not have a lot of time to make adjustments. The pilot would check his height and had to decide to continue the landing or abort. By now the runway lights should be visible for the final approach:
https://youtu.be/8UsPYerEwiA
The fifth clip shows the aircraft flying along the beam. It starts in the centre, moves to port into the dash zone, corrects but overshoots to the starboard side into the dash zone. The aircraft ends back onto the beam:
https://youtu.be/H8xpMC0SJ9I
The final clip shows all signals in a single clip, the aircraft is flying in the dot-zone and the VEZ and HEZ are triggered in quick succession. Not a very realistic scenario, but it allows to different signals to be compared:
https://youtu.be/sb9Llv5B6xc
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