APCO 25 and system types

[Landman]

I live in an area where the various public safety agencies all share a large type 1 Smartnet analog 800 MHz trunking system with nine fleets of up to 15 subfleets each. The system is slowly going through the process of converting to an ASTRO APCO 25 compliant digital system. I want to know if the system would have to be converted to type 2 format before the switch to digital can be made or can it retain the type 1 format with its current fleetmap. I wanted a little heads up before they start digitizing the transmissions, such as will I see talkgroup ID's suddenly appear on my scanner in type 2 format instead of type 1. If this digital scanner finally does materialize, I just wanted to know what format I should expect to program it in, type 1 with the proper fleet map or type 2.

[batdude]

ain't no such thing as type 1 astro trunking.

my bet is that they start converting everyone on a per-agency basis and convert individual channels of the system to astro.

i would also bet that you'll get the Astro IMBE trunking (*NOT* astro-25 trunking) to maintain compatibility with all those radios in the field

[Elroy Jetson]

Astro trunking of the 3600 baud control channel, analog talkgroup compatible version is based on Type II addressing.

Astro trunking of the 9600 baud control channel, pure digital with NO analog talkgroup compatibility, known as Apco Project 25 trunking (or Astro 25) uses a totally different addressing scheme. It is not type I and it is not type II. I gather that it actually uses an IP-like addressing scheme, or at least it CAN use that. Getting in-depth knowledge of these systems is not particulary easy.

Elroy