P25 is a standard for the manufacturing of interoperable digital two-way wireless communications products. Sometimes also known as Project 25 or APCO P25, this is a user-driven standard, it is not industry – or Federal government – driven standard.
P25 allows for improved communications within and between agencies – especially emergency service providers. Such intra- and inter-operability is necessary for coordinating efficient and timely responses in our post-911 world.
High Frequency (HF) Radios operate in the frequency range of 3MHz to 30MHz
HF radio is primarily designed to enable long distance mobile communication in areas where the mobile telephone network is not available. HF Radio is infrastructure independant useing the Ionosphere to refracft the radio signal rather rely on Satelites or Repeaters to achive long distance communications.