Bigger is Better
With the calendar saying that the date is May 6th, you would think that winter is over, but backroading in the Rockies reminds you that we've got a ways to go yet!
Mind you, the snow at the lower elevations where I'm located arrived the day before, and will disappear quickly, although the upper reaches of the Rockies will have snow for a while yet.
In this photo, you find me about to change out my fixed 30 meter monobander antenna for my 10-80 meter gearmotor antenna.
Although I could have changed out just the coil for one covering the lower band that I planned on operating on, my 10-80 meter gearmotor antenna with its accompanying whip and caphat is a much better choice due to the fact it is a much more efficient antenna with its 3 inch coil when working the lower bands.
Of course when conditions are right, it doesn't really matter what your using for an antenna, they will work somewhat. Depending on your dedication to working HF mobile, and if your mobile will allow it, bigger is better when it comes to antenna efficiency while operating HF mobile.
Besides the type of antenna, where the antenna is mounted on the mobile makes a difference as to how efficient the overall antenna system will be.
On 80 meters with a small inefficient antenna mounted on the mobile with no metal mass beneath the antenna, your HF mobile will operate at about 1% efficiency,
Mount the antenna so that the metal mass is beneath the antenna, your efficiency will rise to about 5%. Add a caphat to the mix, you may achieve about 8% efficiency!
Expand the photo for a closer look.....