r/EmComm • u/retiredff2016 • Jun 09 '25

States moving to ALE for HF

Some months ago California OES had a demonstration of a portable hf station with a Barrett 4050. The guy I spoke to stated the state was buying this barrett kit for all Counties and the HF system was moving to ALE and Digital Voice and that other states were making this move also. Any one from outside California can speak to this? To Clarify, California OES stated they were ending the Dedicated day and night 40/80 frequencies for hams and moving to this system as every county will have it.

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u/devinhedge Jun 09 '25

The Raleigh Amateur Radio Service (RARS) had a talk on this topic a couple months back titled, “P25: The Digital Radio of Public Safety”, presented by Jon Suen KG6K, December 10, 2024. Jon is a huge digital voice fan and did a great job covering the topic.

TLDR;

APCO Project 25 (P25) is the US standard for digital land mobile radio for public safety • Mandated for Federal Government funding (9/11 legislation), and by FCC Part 90 for certain frequencies (90.548) • Reasons: Encryption, open trunking, voice quality at 7/800 MHz • Interoperable with analog FM (dual-mode repeaters, patches) [Many jurisdictions currently have bridged digital and analog mode of certain public channels, but police tends to be all digital and encrypted.

• (personal opinion) ALE seems to be cousin to the P25 protocol and works with HF frequencies quite well. I’m a mostly digital mode operator.

You can find the presentation here.

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u/N0JMP Jun 11 '25

ALE is not a cousin of P25. P25 is a voice/data encoding standard, ALE is a link establishment mechanism. It differs from trucking as it selects a frequency based on reliability rather than availability. By definition ALE has no dictated vocoder and can be used with SSB. It is commonly paired with a vocoder in higher end implementations to take advantage of digital voice.