About acquiring information. Listening is far more important than transmitting.

Imagine having a receiver that covers almost all of the useful radio spectrum. Public service, ham, satellite, military, FM broadcast, everything.

Even if the information is encrypted, if you are familiar with the routine traffic loads, you will notice when the traffic load changes. In the military this is called operational tempo or OPTEMP. A sudden gigantic increase of all the local police frequencies may indicate that something "interesting" is happening. You might then switch to some of the local industrial frequencies like Power company or ambulance services. Local media frequencies like remote pickups or perhaps fire services.

Many of the digital services can easily be decoded. Paging, equipment service transmissions (river level, power monitors etc.) are easily decoded.

Many satellites are easily received. Weather sats. send color or enhanced color images directly to your receiver.

And the equipment is very cheap. Less than $30 will buy a small dongle which you plug into your computer. Download free software and you will have a very wide range receiver. Some cover from 1 Mhz to 3 ghz.

These are software defined receivers (SDR). Here is a youtube demo of some of the applications.

SDR Demo.

Amazon sells one here

Amazon

For non-computer literate folks the learning curve is high, but very much worth the effort. Geeks will jump right in and have no difficulty following the many youtube and other learning resources.

But this is not something to buy and hold until something bad happens. You will need to spend a lot of time learning your local electronic environment and exploring the technical issues around encryption, satellite tracking and other complex issues.

Information directly from the source is invaluable, but you must train yourself to understand what you hear and see.

Listening is far more important than transmitting.