Phase I vs Phase II

My local county uses a really good top of the line Phase I P25 Hariss system. Would they ever need to upgrade to Phase I. What's the pros and cons of Phase I and Phase II. A lot of my area is Phase I.

It's all about using the spectrum more efficiently:

https://www.taitradioacademy.com/topic/what-is-the-difference-between-phase-1-and-phase-2-1/

https://wiki.radioreference.com/index.php/Project_25

Hello,
hope I can help,
In short, Phase II has a better spectrum utilization It has 2 voice channels, and uses a better voice codec but it is not backwards compatible with Phase I. Meaning your county would have to buy all new radios, a quite expensive project, I think $2-3000 or even $6-7000 a piece.

On the other hand P25 system has its downsides, there have been at least 5 well publicized security flaws, so an upgrade to Phase II should be well thought out

A possible alternative for your county is a similar standard called Tetra however used mostly oversees. It has more advanced full duplex voice and data and messaging features. the radios are also much cheaper think below $1000,

Short answer - Phase 2 nearly doubles the number of voice channels on the same frequencies.

Phase 1 is better as far as sound quality as far as listening is concerned. Phase 2 may have double the talk capability but the audio between the dispatch and the units vary wildly. I dont have any clue why!

airman9000 said:

Hello,
hope I can help,
In short, Phase II has a better spectrum utilization It has 2 voice channels, and uses a better voice codec but it is not backwards compatible with Phase I. Meaning your county would have to buy all new radios, a quite expensive project, I think $2-3000 or even $6-7000 a piece.

Click to expand...

Not totally accurate. A phase 2 system is capable of supporting Phase 1 radios and talkgroups. The system could be upgraded to be phase 2 capable, but still use phase 1 radios.

You would be correct though that in order to take advantage of the additional capacity of phase 2, new radios would need to be purchased that are capable of using phase 2. This is something that can be implemented in steps over a period of time. Maybe something like this:

Year 1: Upgrade county sheriff and pd radios
Year 2: Upgrade county fire department radios
Year 3: Upgrade other county agencies (may be split into multiple years as needed).

Mike