The Waller Flag can also be used horizontally. The vertical field has a deep null at the front, The vertical field from 1620 KHz AM station shows a perfect butterfly diagram . The difference in gain between the WF vertical and the horizontal HWF is 20 db down. The null at 320 degree is actually the direction of the arriving signal, the program always rotates the plot for a max signal close to 0 degree.

I received  horizontal and high angle signals only on 80M, the noise on 3.8 MHz including atmospheric noise was quieter on the horizontal WF. On 40 m the HWF has a well defined patter with deep nulls on each side and a good front back. It tells me that the antenna is working well but is too close to the ground.

Most of the time there are no horizontal signals at 20ft high for MW or 160m, the arriving signals are shorted circuited by the ground, Tests on 3.5 or 7 MHz shows a different situation and there are plenty of horizontal signals.

Even at 20ft I can hear DX on Top Band, signals from Europe and South America on 160m  was two S units down on the HWF, much better copy on the vertical antenna but just the fact that I can hear DX on the HWF is a first step to motivate me to keep my study with the HWF. 

On 80m the horizontal WF works very well even a 20th ( 6m) high. Signals from Asia was easy to copy . The antenna shines on 40m, fantastic DX reception. I’m planning to have one Horizontal Waller Flag at 116 ft high , right  on top of my vertical TX antenna.