Amateur Radio


The three most commonly used Digital Voice modes in Amateur Radio are:

If you have not already, you will frequently hear the term hotspot in discussions of Digital Voice.
A hotspot is essentially a personal micro-repeater. That is, it is a small device which contains a very low power transceiver. It connects to The Internet and acts as a bridge between your radio and a digital reflector.
There are a number of these devices available. Some connect via the USB port on your computer, while others connect directly to your router or Internet modem. In other configurations, a Raspberry Pi is employed as part of the system.
Here are links to some of the available hotspots. There are others.

NOTE: very recently, Sharkrf has stopped production of the original Openspot. They are in the process of manufacturing an upgraded model which will include wifi instead of the wired RJ-45 connection in the original. The new Openspot2 is supposed to be available sometime this fall.
The Zumspot, which was disappearing from the market has also come back to life recently. It is being sold by Ham Radio Outlet.
See Details Here
I found a very helpful document which outlines the steps you must take during initial setup of the Zumspot. A major part of this discussion explains the Pi-Star software. You may read or download it here.
For an excellent compilation of information on hotspots visit Hanging Out With Hotspots
The ThumbDV is a USB device which enables you to operate D-Star using the sound card of a computer without a radio.

To help get you started, here is a brief overview of the structure and terms you will encounter as you explore the digital modes.

D-STAR

In general, you connect to D-Star either through a repeater which is on the gateway or you use a hotspot. The gateway is an Internet structure which enables you to connect to various reflectors. A reflector is a connection which enables a number of users to communicate. It basically handles data traffic. In D-Star, reflectors are currently designated using one of the following prefixes: REF, XRF, DCS or XLX. Reflectors are located throughout the world. There are listings which show you where various reflectors are located and how they are used.
D-Star uses two digital modes: DV (for simplex and hotspot operation) and DR (for duplex repeater operation). There are also a number of commands which are used to perform tasks within the system. You can initiate a local conversation, make gateway calls for global conversations, link and unlink to reflectors and request status information.
To get started with D-Star, you must register your callsign with a Gateway in order to be able to access the network. Refer to the other links on this page for registration guidance.

DMR

As with the other digital modes, you can connect to DMR using a repeater or through your own hotspot. DMR is somewhat more stringent in its structure than other modes but with the introduction of the Brandmeister Network, it has become easier to use.
In general, DMR uses a concept called TalkGroups to handle traffic. A TalkGroup is designated using a numeric value. If you access DMR through a repeater, you will usually have access to a number of talkgroups through that repeater. Different groups have differing scope. That is, some talkgroups are focused on particular geographical areas, while others are more global. In addition, some talkgroups are intended to be used for short contacts while others are available for longer conversations.
DMR also uses a technique known as TDMA (time-division multiple access) which splits operation time into two slots: timeslot1 and timeslot2. When you set up your channels, you must use the correct timeslot or you will not hear anything.
When you program a DMR radio, you will hear terms like CodePlug, Channel, Zone and Digital Contact. A codeplug is nothing more than a computer file which contains settings and data information. It contains the frequency pairs for repeaters, the contact information for talkgroups and individuals and other details needed to program the radio. In other words, a codeplug contains information on radio settings, contact data, channel and zone information. A channel is the package of information which defines a selection on your radio's channel selector (like a memory channel in analog terms). A zone is just a group of channels. The number of channels available to be placed into a zone depends on the radio you are using. Digital contacts are used to define the destinations such as talkgroups or individual stations.
In order to access the DMR network, you must register and obtain a Subscriber ID. Refer to the other links on this page for registration guidance.

Fusion

C4FM Fusion is a Yaesu proprietary digital mode. If you want a Fusion radio you must purchase a Yaesu product. However, you can use either a repeater or hotspot to access the Fusion network.
C4FM Fusion utilizes two types of reflectors: YSF reflectors(WiresX), and FCS Reflectors which are geographically organized. Each reflector contains 100 rooms. Fusion repeaters are unique in that they seamlessly support both FM analog and C4FM Fusion digital communications. The latest Yaesu transceivers also offer automatic sensing so that you can operate in either analog or digital mode without changing anything on your radio.
The FCS reflectors have the designation FCS001 (Europe) FCS002 (United States) and FCS003 (Canada). Within each, the rooms are used to select specific regional areas.

Those interested in the TYT MD380 or MD390 can learn more about them on my MD380/MD390 Tutorial and Information page
Blind users in particular, will find the tutorial helpful.

For anyone interested in an entry-level C4FM/Fusion radio, you may listen to my basic tutorial of the
Yaesu FT-70DR handheld

I recently gave a presentation to our local radio club called:
Practical D-Star
It is a PDF and you may read or download it.

For another overview and comparison of the three digital modes, read the following article.
Digital Voice Modes: Overview And Comparison

The following is a list of helpful links which cover various aspects of the Digital Voice modes. For blind and low-vision users interested in D-Star, read and listen to the information on the Kenwood TH-D74A handheld. I have that model and find it to be a fantastic piece of equipment!