CHECK YOUR CO-AXIAL CABLE
More often than not your coaxial can be the culprit for weak signal strength coming into your RV. In the industry, it is called attenuation. This equates to the measurement of loss of the signal over a certain distance.
In many cases, it is as simple as replacing the old coaxial cable with a new efficient isolated RG-6 cable with up your connectivity and give you more channels.
Keep an eye and check on the cable you are using RG-59 is known for being a little sub-par, the required information will be written on the side of the cable.
Co-axial Cable Connections
Electromagnetic interference and signal noise can be got on top of by using better shielded RG-6 cable. Most of the time you will notice a significant difference in quality and improvement.
Plus everything today is moving into the digital realm, and the RG-6 is way more digital-friendly than it's predecessor. The RG59 attenuates and has more signal loss overall, so a witch could fix your issues without having to use the amplifier.
Every year when you bring your RV out and dust it off, it's a good idea as part of your overall maintenance check to study your co-axial that links up to your TV, antenna or even satellite. Look for any frays, rips or tears, if there is anything suspect then time to replace it as it's too much of a risk when you are in the outback with no connectivity.
BUY A BETTER caravan TV aerial
This is always the most obvious option, especially if your keep questioning and double guessing yourself, buy a better quality one. There are plenty of options on the market today, both Directional and Omni-directional.
Ask your supplier what aerial suit best for where you want to travel as different stations emit different frequencies, once you know you should be fine.