Embedded Files
Frequently Asked Questions on Repeater Coordination
Frequently Asked Questions on Repeater Coordination
What is frequency coordination?
Basically, it is a form of voluntary participation in an organized program intended to keep interference between repeaters and their users to a minimum. To do this, repeater trustees work with UNYREPCO which maintains a database of repeater frequencies in active use (as well as new repeaters which are under construction but may not yet be in operation). UNYREPCO assists the proposed repeater trustee in selecting operating frequencies (and other technical details) which will, hopefully, be compatible with other existing repeaters.
Who is my local UNYREPCO representative?
Your local UNYREPCO representative is, first, a volunteer. In the UNYREPCO, he/she is an individual who lives in your community or region of the state. UNYREPCO is an organization of volunteers who are recognized by the Amateur Radio community as their "coordinator". UNYREPCO's volunteers might participate in the program because they are interested in either the technical or the political aspects of coordination, but they all do it as a way of putting something back into Amateur Radio. These days, no volunteer is in it for the ego! It's too much work! But all volunteers do get some form of self satisfaction out of doing the job, or they wouldn't bother.
Who benefits from frequency coordination?
Everyone does. Trustees of existing coordinated repeaters are assured that the UNYREPCO will attempt to protect their repeaters from interference caused by new repeaters. Likewise, trustees of proposed new repeaters will get knowledgeable assistance from UNYREPCO in selecting frequencies for their repeater, so that they can feel confident that their new operation will not adversely affect any existing repeaters, and they should experience little interference on their new repeater.
How does frequency coordination work?
In order to make a recommendation, the UNYREPCO needs some data about the proposed new repeater, such as its location, antenna height, ground elevation above sea level, transmit power, etc. These items all affect, to one degree or another, the repeater's area of coverage. UNYREPCO will review the data on the new repeater. Then in conjunction with the data in the coordination database, the local frequency coordination committee member may assist the applicant in finding an optimum frequency pair.
UNYREPCO studies the parameters of nearby co-channel (same frequency) and adjacent-channel repeaters, and with the established, adjacent frequency coordination councils, to make sure there are not any valid objections to the new repeater. Once a new coordination is issued, there is a six month construction period to get the new machine on the air. If it's not on by this deadline, the coordination is allowed one additional six-month period (upon written request), after which the coordination is subject to cancellation. This keeps UNYREPCO's database from filling up with "paper" repeaters.
For more detailed information please look at the UNYREPCO Frequency Coordination Policy.
Is frequency coordination required?
No. Participation in a frequency coordination program is strictly voluntary. No Amateur Radio frequency coordinator has any "authority" to tell a repeater sponsor what he can, or cannot do. However, the Federal Communications Commission (FCC) and the amateur community has recognized that participation in a frequency coordination program by repeater trustees is in the best interests of all Amateurs. Therefore, FCC rules (Part 97.205c) have been adopted;
§97.205 Repeater station. (c) Where the transmissions of a repeater cause harmful interference to another repeater, the two station licensees are equally and fully responsible for resolving the interference unless the operation of one station is recommended by a frequency coordinator and the operation of the other station is not. In that case, the licensee of the noncoordinated repeater has primary responsibility to resolve the interference.
Essentially, this states that the trustee of an uncoordinated repeater bears the primary responsibility for resolving any interference between his repeater and another repeater which is coordinated. Likewise, the trustee of an uncoordinated machine cannot expect much help from UNYREPCO.
How can a coordination be canceled?
If a proposed new repeater never gets on the air or if an existing repeater goes off the air, the coordination may be subject to cancellation after a limited amount of time (not in operation after 6 months or more from date of coordination)
If any of the primary parameters which affect a repeater's coverage area are changed by the sponsor, the coordination can be voided. For instance if it gets moved to a different location, of if the antenna height or transmitter power are changed, the changes would affect the coverage area, possibly creating new interference problems for the repeater's neighbors. UNYREPCO will soon require sponsors to file periodic up-dates in order to retain their coordinations. UNYREPCO also relies on monitoring efforts to keep abreast of activity.
For more detailed information please look at the UNYREPCO Frequency Coordination Policy.
Are other Amateur Radio stations also coordinated?
Yes. In addition to repeaters, UNYREPCO also coordinates packet/digital operations and other operations associated with repeaters, such as links between a repeater's remote receivers and the main site, etc. In addition, UNYREPCO also can assist in your understanding of the many interrelated frequency rules that apply to repeaters, remote-bases, links, remote control, auto-patches, cross-band operation, packet and so forth.
What kind of problems does UNYREPCO have?
Nowadays there are probably 2 main problem areas:
First are problems created by the few uncoordinated machines which pop up from time to time.
Second, are problems caused by the proliferation of dual-band transceivers with built-in cross-band repeat capability.
Unfortunately, a poor choice of frequencies can cause interference problems which may go totally unknown to the user of the dual-band radio.
There are a small number of uninformed operators who abuse cross-band repeater capabilities causing unintentional, but sometimes even malicious, interference.
Other problems are caused when UNYREPCO is not informed of changes to existing repeaters, changes of sponsor's mailing address, etc.
What other activities does UNYREPCO conduct?
UNYREPCO is involved in "band-planning" or "spectrum management" efforts, often in association with adjacent-area coordinators and is a Charter Member of and Certified by the National Frequency Coordinators' Council, Inc. - currently UNYREPCO's representative is the NFCC Secretary, but prior representatives have been NFCC President.
Different special-interest groups include the packet community, the DX Cluster community, weak-signal/SSB/CW interests, FM simplex users, ATV'ers, etc. All of these other interest groups need to be considered when "band-plans" are being developed or revised, so frequency coordinators need to keep them in mind as they conduct their spectrum management effort. Band-planning/spectrum management cannot be done in a vacuum! Good familiarity with the frequency coordinator Rules is helpful here, since repeater, remote-control, link and remote- base operation is prohibited in some parts of the Amateur HF, VHF and UHF bands.
UNYREPCO maintains a list of technical experts who are available to assist repeater sponsors in resolving technical problems. They also maintain a list of Amateurs with the capability and expertise in finding interference sources, both from spurious emissions, as well as malicious interference. Also some coordinators maintain, or have access to, a fairly extensive library of technical information on equipment, system designs, and maintenance. These resources are all available to the sponsors of all coordinated repeaters in the area.
Special thanks to SERA for portions of this document
Page updated
Report abuse