DAPNET (Decentralised Amateur Paging Network) is a free global paging network created and maintained by

amateur radio Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emer ...

enthusiasts. Messages can be received on commercially available

pager A pager, also known as a beeper or bleeper, is a Wireless communication, wireless telecommunications device that receives and displays Alphanumericals, alphanumeric or voice messages. One-way pagers can only receive messages, while response p ...

s that support the

POCSAG Radio-paging code No. 1 (usually and hereafter called POCSAG) is an asynchronous protocol used to transmit data to pagers. Its usual designation is an acronym of the Post Office Code Standardisation Advisory Group, the name of the group that devel ...

protocol and are tuned to the appropriate

frequency Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio ...

History

A similar ham radio project called FunkrufMaster was quite popular around 2000. It was based on

AX.25 AX.25 (Amateur X.25) is a data link layer protocol originally derived from layer 2 of the X.25 protocol suite and designed for use by amateur radio operators. It is used extensively on amateur packet radio networks. AX.25 v2.0 is responsible for e ...

-technology and the former Packet Radio Network. Because of the upcoming HAMNET- and IP-Protocol era, a successor was needed. Members of the ham radio activity group at

RWTH Aachen University RWTH Aachen University (), in German ''Rheinisch-Westfälische Technische Hochschule Aachen'', is a German public research university located in Aachen, North Rhine-Westphalia, Germany. With more than 47,000 students enrolled in 144 study prog ...

designed and developed DAPNET from scratch as a modern software approach. As of March 2018, over 90 transmitters were already in permanent operation, and the coverage area included parts of

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

, the

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

, and

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

, with

Raspberry Pi Raspberry Pi ( ) is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in collaboration with Broadcom Inc., Broadcom. To commercialize the product and support its growing demand, the ...

-based personal hotspots extending coverage around the world.

Technical specifications

The recommended frequency for DAPNET is 439.9875 MHz, which is part of the

70-centimeter band The 70-centimeter or 440 MHz band is a portion of the UHF radio spectrum internationally allocated to amateur radio and amateur satellite use. The ITU amateur radio allocation is from 430 to 440 MHz; however, some countries, such as ...

dedicated to amateur radio use. The transmitters are networked, some via HAMNET, some via the Internet. The standard paging protocol

is used for message transmission. For a low-power transmitter you can use

with and MMDVM-modem installed, and to make the coverage area several miles, a radio amplifier needs to be added to its output.RasPager - Simple low-power Transmitter
/ref> The coverage area of the transmitter can be up to 20 km (12 miles), depending on the terrain and the height of the antenna.

Receivers

Skyper and AlphaPOC pagers are particularly popular for receiving messages. They can be easily tuned to the desired reception frequency and also offer many other possibilities, such as receiving bulletins - messages sent to all recipients. However, other brands of pagers can be customized accordingly or

Flipper Zero The Flipper Zero is a portable multi-functional Security hacker, hacking device developed for interaction with access control systems. The device is able to read, copy, and emulate Radio-frequency identification, RFID and NFC tags, radio remote ...

can be used. Messages can be sent via a multilingual website as well as

Android Android most commonly refers to: *Android (robot), a humanoid robot or synthetic organism designed to imitate a human * Android (operating system), a mobile operating system primarily developed by Google * Android TV, a operating system developed ...

and

iOS Ios, Io or Nio (, ; ; locally Nios, Νιός) is a Greek island in the Cyclades group in the Aegean Sea. Ios is a hilly island with cliffs down to the sea on most sides. It is situated halfway between Naxos and Santorini. It is about long an ...

apps.

References

External links

hampager.de
{{Digital_modes Radio paging Digital amateur radio