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  • Roaming is a feature in some vehicular and handheld radios that provides seamless coverage among different repeaters without requiring the user to physically switch channels as they change locations. It allows individual repeaters on different frequencies to appear as a single integrated network to provide very reliable wide-area coverage.
  • The roaming feature automatically steers the radio to a different repeater site if the current site’s signal strength drops below a certain threshold to provide seamless coverage. In its default (or “passive”) mode, the radio constantly measures a repeater’s signal strength when activity is present, or through short polling “bursts” transmitted by the repeater. When the signal weakens to a certain threshold level, the radio begins to step through a pre-programmed list of other repeaters (a Roam List) until it finds one that meets or exceeds the signal threshold. The user will then transmit and receive on the channel selected by the roaming feature. In addition to passive mode, “active” roaming mode can also be enabled. Under Active, when the user presses their push-to-talk (PTT) button, the radio will sequentially transmit a short “wake-up” message (30-60 milliseconds) to each repeater in the Roam List until it finds a repeater that meets the signal level threshold. The radio then remains on the identified repeater and gives the user a go-ahead tone. One Roam List is created for each network talkgroup. Each list can contain 15 or more repeaters sites. When a channel position is configured for Roaming, it cannot be configured for scanning (these features are mutually-exclusive). However, Group Lists can still be used.
  • No; these features are mutually-exclusive. As of this date, most radio models only allow you to assign a Roam List or a Scan List to a given physical channel, not both. Presumably this is because while roaming, the radio must constantly step through each repeater in the Roam List to measure its signal strength; this would constantly interrupt scanning and lead to unacceptable scanning and roaming performance. However, the Group List feature can be used in place of scanning under certain conditions. See ‘What is a Group List”.
  • The Group List feature in vehicular and handheld radios allows the radio to monitor more than one talkgroup on a given channel position, without having to use scan. For example, to hear messages from either the Worldwide or North America talkgroup without scanning or switching channels, you create a Group List containing both Talkgroups, and assign that Group List to a physical channel on your radio. One significant limitation on Motorola radios is that you can only listen to talkgroups that share the same timeslot that is programmed for that physical channel position. In Hytera radios, the physical channel position can be configured for a feature called “Pseudo Trunk” that allows the radio to listen for messages on either timeslot. This allows a Group List to contain talkgroups from any timeslot. Groups Lists are compatible with Roaming. Thus, if you assign a Group List to each repeater included in a Roam List, you will hear transmissions from those Group List talkgroups when you roam to that specific repeater.
  • In order to fully understand dynamic talkgroups, you must first grasp the concept that there are only two timeslots within Conventional DMR.

    These timeslots can only have one active audio path at a time.

    In DMR of Anarchy we use timeslot 2 for the primary network talkgroup (5150) and timeslot 1 for the larger or more distributed talkgroups.

    In an effort to keep the timeslot locked to a particular talkgroup, while that talkgroup is active, we kill the audio from the other talkgroups on that timeslot, so the other talkgroups will not hijack the timeslot  being used.

    With only a few talkgroups per timeslot this is only a minor problem.

    But as the number of talkgroups increase or the amount of traffic per talkgroup increases, the local user cannot get into the local repeater on a timeslot that is being used.

    This is where dynamic talkgroups can help..

    What dynamic does, is it keeps the talkgroup or groups inactive until a user wants to use a particular talkgroup. When the user transmits on that dynamic talkgroup, a timer starts that is reset on each local keyup, and allows the conversation to take place.

    This process gives the local user the best chance to activate what they want, when they want it.

    Now the downsides:

    If a local user wants to just listen to one or several talkgroups in a scan. there would be NO traffic for any talkgroup that is dynamic.

    The second issue is Roaming, which will NOT work for talkgroups that have dynamic talkgroups as members of the Roaming Group. This is because there is no way to ensure the talkgroup you are Roaming is active.
  • Static talkgroups are those talkgroups configured by the cBridge administrator to be always enabled on a particular timeslot. This allows extended monitoring without the need to transmit in order to keep the talkgroup active. Individual repeater listings on this website will list the static talkgroups, and those are the only talkgroups you can expect to hear traffic on unless you or another user activates one of the dynamic groups as described above.
  • Inconsistent transmit audio is DMR’s greatest weakness. Until a technical solution is found it is incumbent upon all of us, when able, to adjust our radios to ensure that our audio is consistent with others on the network. Modern Motorola and Hytera radios with up-to-date firmware work pretty well with automatic gain control (AGC) turned on. Other radios may need adjustment. As audio levels are consistent across different networks, avail yourself of the tools available on the Brandmeister network to set audio levels (VU meter on the Hoseline). On our network, you could find a busy talkgroup where all of the users have about the same audio amplitude, and then, without touching your volume control, switch to the Echo Test talkgroup and see if your audio level matches theirs. When an experienced DMR operator tells you your audio gain is too high or too low, listen to them and make adjustments. None of us wants to be the audio police, but consistent audio levels among users makes the network more enjoyable to use for all of us.

    Note that Motorola radios do have a paid entitlement called “Receive Audio Leveling” which masks the problem for the user of the radio with the entitlement intalled.

  • It depends… To use a cBridge-based amateur network (like DMR of Anarchy or DMR-MARC), a repeater must be capable of running Motorola's IP Site Connect software. Motorola doesn't license this technology for use on third party repeaters, so any repeaters connected to those networks must be Motorola.

    The Brandmeister system is more open, which allows not only Motorola repeaters to connect, but also Hytera and various homebrew repeater types.
  • In addition to voice, the DMR protocol supports other communication modes.

    GPS: Many higher-end DMR radios have GPS receivers which can be configured to send location data to a central server. This is commonly used on transit buses and other commercial transportation services. Due to limitations of the cBridge product, GPS isn’t supported on DMR of Anarchy. Please use other technologies (APRS, etc.) for radiolocation if needed.

    Text Messaging: “The nice thing about standards is that there are so many to choose from.” This saying is very appropriate for DMR text messaging. At least three formats exist: DMR Standard, Motorola Standard and Hytera Standard. None are compatible with each other. Experience shows us that hams new to DMR want to play with text messaging, but the novelty wears off quickly. Because it serves little purpose in the ham world and is very resource intensive (tying up repeaters), the DMR of Anarchy network does not support text messaging.

    Call Alert, Radio Check, Remote Monitor, Radio Enable, and Radio Disable: Like text messaging, there are compatibility issues, but these are supported by DMR of Anarchy. Use caution, as some of these features can result in an inoperable radio.
  • As DMR was created for business and not amateur radio, some of the features are a bit difficult to understand. Three call types exist on DMR:

    Group Call: This is the mode used by DMR of Anarchy and most other ham DMR networks. The idea is that you can call multiple people within the same group and they will all hear you. These Group Call IDs are also commonly known as Talkgroups.

    Private Call: This mode is used on commercial systems to make calls between two radios, from one radio ID to another. As Private Call ties up a timeslot on all involved repeaters and makes it unavailable for other users, the use of Private Call is discouraged on the DMR of Anarchy network.

    You may populate private call IDs in your radio so that a name and callsign will display upon receipt of transmissions from other callers, rather than their radio ID number.

    All Call: This mode is used on a commercial system to call all users on the system. It is not supported on the DMR of Anarchy network.
  • See the “More Information” section of this website.
  • No. The 5150 talkgroup is not available to other systems or networks. Brandmeister systems can use our 31666 talkgroup to talk with users of our system.
  • Some of our talkgroups are patched to Brandmeister. Unlike Brandmeister, only talkgroups specifically programmed into our cBridge are available for use. If you don’t see a talkgroup listed on the listing for an individual repeater, that talkgroup is not available.
  • Both the cBridge and Brandmeister serve the same purpose, in that they’re both essentially talkgroup servers which are used to interconnect a number of repeaters together to form networks.

    Brandmeister is a network. It is free to join and use, and is administered by a group of volunteers throughout the world. It has many advanced features, such as intelligent call routing, APRS, support for multiple repeater brands, hotspot support and an audio archive system called Hoseline. Repeater owners connected to Brandmeister can setup which talkgroups are static and timers to activate talkgroups temporarily for scheduled nets. Otherwise, all configuration is fixed by the global administrators and developers. All repeaters are required to carry all talkgroups, making it impossible for a repeater owner to control what traffic is carried by his or her repeater. With hundreds or thousands of talkgroups available and only two timeslots, contention can become problematic.

    The cBridge is a commercial product (sold in America by Rayfield Communications). While it only allows connections from Motorola repeaters, it offers maximum configurability with regard to talkgroup placement and connections to other systems. We have found cBridge networks to be more reliable and have less contention for timeslots with fewer talkgroups available, which is why we’ve chosen the cBridge.

    With the explosion of inexpensive hotspots available for the Brandmeister network, it is relatively easy for users to have the best of both worlds: A reliable cBridge-based repeater and a hotspot where the end user is free to change talkgroups on the fly without impacting other users of the system. Win-win!
  • The founders of DMR of Anarchy firmly believe that all DMR users should know how to create and edit codeplugs for their radios. Relying on canned codeplugs will leave users at a serious disadvantage down the road when system changes require codeplug updates. Our recommendation is that you learn to program your radio yourself, asking others for assistance. All of the required information (frequencies, color codes, timeslots and talkgroups) are available on the individual repeater pages.
  • Disable ARS/RRS and any GPS beaconing functionality as they are not supported and will cause disruption to our network.

    Motorola users may enable some of their advanced features to improve reliably with our network. Options are typically on a per-channel basis:
    Allow Interruption
    Transmit Interruptible Frequencies
    Enhanced Channel Access

    (Note: Hytera transmit interrupt is incompatible with the cBridge)
  • When a repeater loses its Internet connection for any reason but remains on the air, that repeater is said to be off-network. An off-network repeater operates in stand alone mode, meaning the talkgroups are still operational but all connections to other repeaters are down. Only users using the same repeater can hear each other.
  • There are a number of things which can cause the activity light to come on. Here are some examples:
    DMR traffic on a talkgroup you’re not
    DMR traffic on the other timeslot
    Analog traffic or interference on the frequency
    The Morse Code (CW) ID of the repeater
    DMR digital data
    Repeater beaconing, used for roaming
  • Some repeaters may have private talkgroups for use by the repeater owners or private amateur radio clubs. Unlike with analog repeaters, it is possible for closed systems to share the same repeater as an open system using different talkgroups. Please respect these private talkgroups and remain off of them unless you have permission from the repeater owner. Unless specifically approved, only talkgroups listed on each of the repeater pages may be used.