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We will be discontinuing IRLP service on the VE6HM system in the near future. EchoLink will be unaffected by this change.
What is P25?
What is P25?
P25, also known as Project 25 or APCO-25, is a digital voice mode that is most commonly used in public safety. Many agencies need to coordinate with each other, both on a day-to-day basis and in disasters. In Alberta, this is done through the Alberta First Responders Radio Communication System, or AFRRCS ("eh-fracks")
P25 is a standard created by a joint group of North American public safety agencies in 1989. It has been further established and developed since then. The standard describes the signals transmitted over the air, different functionalities for transporting data and voice, and different interfaces for other systems, among other things.
P25 uses a multi-band excitation vocoder, the same as DMR, D-STAR, Yaesu Fusion, and NXDN. P25 Phase 1 uses a 12.5kHz channel with Continuous 4-FSK Modulation (C4FM) just like DMR and Fusion.
What radio do I need?
What radio do I need?
Unlike the other digital modes you may be familiar with, there are no P25 radios designed for amateur use. P25 radios are designed for public safety or commercial use, so the best way to get into P25 is to look for used commercial radios.
The Motorola XTS2500 and XTS5000 series are very popular among radio enthusiasts. Being a bit older, their price has come down significantly. They have been replaced by the APX line of radios, which are still quite expensive even on the used market. It is important to note that, being commercial radios, many are difficult or impossible to program from the front panel and will require a PC with the correct programming cable and software to program. These are not always readily available, so make sure you can get them before buying!
Another important note regarding P25 radios is that most are single-band only! Commercial radios are not typically multi-banded, unlike your typical dual-band amateur handheld. This means that you need to ensure you get a radio that will function on your desired frequency, also known as having the correct bandsplit.
For Motorola, there are four common bandsplits, with two being usable for amateur radio:
VHF (136-174 MHz), also known as "K" split
UHF R1 (380-470 MHz), also known as "Q" split or UHF Low
UHF R2 (450-520 MHz), also known as "S" split or UHF High
700/800 MHz Band (764-870MHz), also known as "U" split
The VE6MC repeater is on 441.5250 MHz, so it requires a UHF R1/UHF Low/Q split radio to operate.
How do I use it?
How do I use it?
P25 systems are very similar to DMR, so if you've used VE6EMS or VE6VPR before, you'll feel right at home. There are a few elements that you need to have set correctly to get talking:
Radio ID - While no official body assigns Radio IDs for amateur P25 like there is for DMR-MARC and BrandMeister, we highly recommend you use your DMR ID for our P25 system. If you do not already have a DMR ID, you can get one from https://www.radioid.net/register. If you are unsure if you already have a DMR ID, check https://radioid.net/database/search to see if your callsign appears.
Network Access Code - Similar to a colour code for DMR, a network access code, or NAC, is required to connect to a P25 repeater.
Talkgroups—While many digital networks have set talkgroups on every repeater, P25 is much more independent. Talkgroups on the VE6MC repeater are not linked by default, meaning that any talk group can be used for anything, barring a few linked to other repeaters and rooms. Linked talkgroups and some suggestions can be seen here, but remember that any talkgroup that isn't linked can be used standalone on this repeater, not just the ones listed.
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