To ensure full compatibility with the NSW PSN, your scanner should include the following features:

Digital Mode Support: APCO P25 Phase II (TDMA) — mandatory for decoding NSW PSN voice traffic. While some towers still broadcast in Phase I mode, this is being phased out and any scanner with only Phase I compatibility will stop working altogether.

Motorola P25 trunking — must follow control channels and dynamically assign voice channels.

403–430 MHz and 450–470 MHz UHF bands — covers all PSN site frequencies. Most scanners have that capability but if you purchase a scanner from overseas it may cause issues.

Ability to track TGIDs and optionally log Radio IDs (RIDs) for unit identification.

Automatically follow active control channels across sites. This ensures that any communication which moves across different sites will continue to be heard.

Store large numbers of TGIDs, sites, and frequencies; ideally with GPS-based site switching (optional). Most scanners these days have SD Card storage (Micro SD Cards) - this allows for saving of thousands of frequencies or talkgroups with channel names.

The scanner must be able to ignore encrypted talkgroups — since no scanner can decrypt them the scanner should automatically skip these channels to minimise noise and nuisance pick ups.

USB or Bluetooth interface for programming, logging, and firmware updates. Most scanners can be placed into PC Programming mode with each scanner brand having dedicated software to creating and maintaining a database which can the be uploaded to the scanner. While Bluetooth sounds simpler, using a dedicated cable has greater reliability.

Having a built-in GPS or a GPS add-on module will enable automatic site switching based on your location. This is most useful if the scanner is used while moving - such as built into the car dashboard.

Scanning/Searching for unknown TGIDs and then log the activity for the database building is a standard feature these days - as long as you purchase a major brand scanner (such as Uniden).

If the scanner is intended to be used as a handheld device, ensure that the battery life is long enough between charges and that the outer shell and display are of a rugged build. Some scanners are also water proof to a certain standard these days - this may not be important to you if you use the scanner indoors or you purchase a desktop scanner.