Don't worry, we've thought of everything! If you don't have mains power available, we can provide a variety of options depending on what you're looking for.
If you're looking for something super-portable, we offer of couple of clip-on beltpack transmitters: the Parakeet and Parrot. The Parrot requires 2 AA batteries and the Parakeet has built-in rechargeable batteries. Both have a range of approximately 50m.
If you want something portable but a bit more powerful, our Falcon's might be more up your street. Both with a range of 300m in optimum conditions, they come with or without phono/RCA inputs depending on the model.