I don't sell any of these nor do I receive any remuneration if you buy them, and I have not personally reviewed all of them, they are listed here to give you perspective
Introduction
there are a variety of radio devices available depending upon needs:
for those going off-grid or for when the internet / mobile phone system goes down such as extreme weather events (strong winds, floods or bushfires knocking out the local electricity grid) it is nice to have other options such as a radio receiver or other remote communication for campers and hikers which does not rely upon local infrastructures
radio may be the ONLY way of communicating to the outside world in a disaster
the following are ILLEGAL in Australia and can result in fines up to $425,000 or 2 years imprisonment1)
2-way radios which are not compliant with Australian regulations (eg. most online Chinese models such as Baofeng)
use of 2-way radio on frequencies other than CB radio channels without a license
mobile phone boosters (but cellular mobile repeaters are permitted)
mobile phone jammers
GPS jammers
WiFi jammers
drone jammers
non-approved radio transmitters - its impossible to work out from the legislation if the very low power SDR transceivers outlined here are legal to possess in Australia or not but seems the universities use them for teaching so I presume they are as long as you don't transmit illegally but I'm not confident at all about their legality for possession - see https://www.legislation.gov.au/F2021L00661/latest/text
unless you have a Ham radio licence, you are NOT allowed to transmit on frequencies other than 2-way CB radio
avoid having radio transmitters such as 2-way radios within 2m of receivers as they will overload them
to minimise noise, move away from or turn off electronic devices that produce EMF noise including LED lights, power sources, etc
HF (SW) is particularly sensitive to noise and ideally needs a long antenna outdoors to match the HF wavelength, although for signals bouncing off the ionosphere, antenna orientation is less critical as the polarisation is dispersed due to the bouncing
if using an outdoor antenna BEWARE of lightning strikes!
if going more than 25 miles off shore, you will need HF transceiver radio as well as an ACMA approved 25W marine VHF transceiver radio plus satellite phone
most coastal radio stations provide regular local weather forecasts on VHF radio, with instructions and broadcast times announced regularly on Channel 16 or 67.
VHF Channel 16 frequency is 156.8 MHz. It is the international calling and distress frequency for marine VHF radio communications, channel 67 is 156.375 and is the supplementary channel for channel 16.
General Mobile Radio Services (GMRS)
similar to CB radio but different bands
in the USA, GMRS is allotted 30 frequency channels in the vicinity of 462 MHz and 467 MHz. They are divided into 16 main channels and 14 interstitial channels
requires GMRS licence but usually no exam is needed (unlike HAM radio licences)
you need to set up a Winlink HF Gateway which involves an amateur radio HF transceiver (could be software defined radio SDR), digital rig control interface, USB sound card, Windows based computer, and specialized Winlink control and modem software
in addition, as a Winlink Sysops you must be approved by the Winlink System Administrator before being allowed to connect to the Winlink network. This means you MUST have a Winlink account, be an active user of radio email, and be willing to setup dedicated hardware with backup power for the task.