Xiegu G1M Longer range coms on a budget

[CharlesHarris]

Frequency, transmission mode and transmitter output are selectable, but transmitter range is affected by efficiency of antennas on both transmit and receive sides, the radiation pattern of the antenna, and also by terrain and atmospheric conditions. Even a low power signal, such as a PMR446 hand-held, with inefficient base-loaded helical antenna having negative gain compared to an isotropic source, can be located and monitored from many miles away by satellites or aircraft using advanced equipment.

While yagi and log-periodic antennas are directional, they still radiate in all directions, although the main lobes of the radiation pattern and the highest gain favors where they are pointed.

To avoid eavesdropping avoid RF-based communications unless encrypted, using spread spectrum or being sent in brief digitized burst transmissions.