Ham Radio
Power: I use solar panels, Victron 100/20 MPPT charge controllers and AGM batteries for all of my ham radio power. To connect power, I use Anderson Power Pole Connectors with crimpers I get from Quicksilver Radio. Between the batteries and all radios I add a power booster. This will give you 13.9 volts even when the battery voltage is low, 10.6 or so volts. That way your radio transmits at full power, and more important, your microphone(s) don't go to "open mic" as they often do when batter power is low. If I don't use a booster, I at least have a volt meter monitoring the battery so I can switch to another if need be.
Radios: to start out, any 2 meter mobile that outputs at least 50 watts and works. I got my first one at a ham radio flea market for $50. If you have your General license, and can spend the bucks, get an Icom 7100. It does about everything except microwave.
Coax cable. From the radio to the antenna. If you want to get every possible db to the antenna that the radio puts out, don't cheap out here. LMR 400 or LMR 600.
Antenna: You can make your own, there are a lot of Youtube videos on that. Or buy a high gain Diamond whip or even a Yagi. Try for as much gain as possible. A Yagi is very directional, you will have to point it towards the station you wish to communicate with. This is usually not good when volunteering at a rally or other event where you need to communicate with operators in various directions.
Masts: Sometimes, to have a usable signal, you need to get your antenna up in the air. 15 to 24 feet up can make a big difference.
Positioning: If you have a poor signal, try moving your antenna (if attached to your vehicle, the vehicle) one foot at at time towards or away from the station you are trying to communicate with. They will ask you to, or you tell them so you aren't both doing it at the same time. A foot difference often makes a huge difference with 2 meter radio.