Is it an Amplifier?

NO! It is a transmitter! The Polar Explorer handles the transmitter processing end-to-end, from microphone or key to antenna. It works with your station transceiver, which then only functions as a receiver. The Polar Explorer interfaces to your transceiver using the CAT interface to obtain frequency and mode information. It automatically follows the transceiver as you QSY or change modes. Your transceiver never transmits; The Polar Explorer handles those functions, and includes a T/R relay to protect your transceiver.