United States Patent: 5,822,314
- Communications system and method of operation. A typical operational function, using timing information inherent in the transmissions, is the encryption/decryption process within the Trans European Trunked Radio (TETRA) standard.
- http://www.freepatentsonline.com/5822314.html

United States Patent: 5,815,799
- Priority system for a wide area transmission trunked communication system. Here is the LTR Multi-Net Patent that explains the signaling protocol.
- http://www.freepatentsonline.com/5815799.html

Genesis Group
- Article describing the basics of trunking together with an industry glossary and available software programs.
- http://www.genesisworld.com/trunking.asp

Nighthawk Communications, Inc.
- Offers VHF and UHF wide area LTR System, sales, rentals and repair services in the Los Angeles area.
- http://nighthawkcommunications.com

NIC Technologies
- Independent service provider of radio communication systems specializing in trunked radio and wireless point-to-point systems.
- http://www.nictechnologies.com/

Base Radio Systems Program
- Provides information on the competitively awarded set of contracts that offer a complete menu of Land Mobile Radio products to all U.S. Federal Agencies worldwide. Managed by the Army.
- http://www.eis.army.mil/brs/

Gould Electronics
- Offers trunked radio solutions as well as shop watch schemes, conventional 2-way radio and fire service communications systems.
- http://www.gouldelectronics.co.uk/

Fylde Micro, Ltd.
- Provides trunking systems to OEMs, dealers, and end users. Includes dealer locator.
- http://www.fyldemicro.com/

Entropia Network
- Commercial wireless voice and data provider with its own trunked radio network in Belgium.
- http://www.entropia.be/

Team Simoco
- Designs, installs, and maintains conventional and trunked radio systems.
- http://www.teamsimoco.com/

Crudele Communications
- Sales and service for two-way radio trunking repeater systems. Conventional two-way including UHF, VHF and low-band. FCC licensing and Nextel Phones.
- http://www.crucom.com/

Champion Communication Services, Inc.
- Provide UHF radio communication products and operate UHF trunked networks providing voice, dispatch and wireless data services. Includes operational area information and a listing of dealers .
- http://www.champcom.com/

Actions Communications, Inc
- Provide voice and data communications using LTR trunking technology throughout the greater Puget Sound area. Includes product listings and service area information .
- http://www.actcominc.com/index.htm

TETRA
- Forum representing users, manufacturers, operators, test houses and telecom agencies for terrestrial trunked radio, an open digital trunked radio standard defined by the European Telecommunications Standardisation Institute .
- http://www.tetramou.com/

Trunking Information
- Information on several Motorola systems, the EDACS system which is operated by the City of Clearwater, as well as conventional frequencies for the Greater Tampa Bay Area.
- http://www.photonick.net/radio/

Land Mobile Spectrum Planning Options
- Article discussing the sharing of trunked public safety radio systems among Federal, State, and local organizations .
- http://www.ntia.doc.gov/osmhome/reports/slye_rpt/appendix.html

GTRAC
- Resources for EDACS TrunkTracking. Includes guides on frequencies, programming, talk groups, and related links.
- http://gtrac.ztn.net/

Dade County Frequencies and Talkgroups
- Provides a listing of aviation, marine, business, and federal frequencies together with links to related resources .
- http://www.kenji-d.com/scanning/