Here are some acronyms and mnemonics my friend Al (VK2VEC) has collected for remembering stuff about radios. Some of them are his, and some of them you may have heard before.

1. Propogation is FAST = Frequency, Antenna, Sun, Time
2. Grey Possums and Brown Rats connect power supplies. (Generator -> Power supply -> Battery -> Radio).
3. ELI the ICE man remembers reactance and inductance. (Recall from E=IR.) Voltage (E) Leads Current (I) in an Inductor (L). and Current (I) Leads Voltage (E) in a capacitor (C).