The new 40m antenna ( LDP ) at the top of the hill performs 1- 3 db better when the band is long ... night.
The original 40m ( IMI ) antenna behind the house performs 1-3 db better when the band is short ...day.
The reason ... the new antenna is at the apex of the will with the ground plain dramatically sloping away in all directions. The antenna behind the house has a ground plain that rises towards the N NE and falls towards the W SW with more or less flat N NW and S SE!
Basically the new antenna has a lower angle of radiation then the old one. Propagation is flicked at best. The Ionosphere is anything but a linear plane that is uniform ....density , location and most importantly its angle all come into play.
Now the 3 db difference is really not all that dramatic. Its not like one antenna is going to get you through where the other doesn't but from time to time that extra S Until would come in handy! I could do without either or antenna and it really wouldn't have a great impact on my 40m operating ability.... for now they both stay!
Up next 14avq ( also at the apex of the hill ) vs the new 1/4 Vert. The 14avq has some radials but they are not optimized for 40m. First I will compare the 2 antennas then I will add 8 radials cut for 40m and do it all over again!
here is the overnight 1am until 7am IMI vs LDP results ...
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