This post is to help those new to digital and DMR get started
Radio etiquette is a little different for DMR. It's usually bad practice to key up a repeater and not say anything. However this is required with DMR. When making a call you want to key the talkgroup once to make sure it's linked then wait a few seconds to make sure the talkgroup is clear before you transmit so you don't talk over an existing conversation.
The 3 talk 3 rule
Unlike analog, digital has a buffer. Transmissions tend to get cut off at the beginning and end if you don't follow this rule. Basically you want to key the radio, wait 3 seconds and then start to talk. You also want to wait a few seconds after you're done talking before you un-key the radio to make sure your transmission doesn't get cut off at the end.
There are other networks but Brandmeister seems to be the most used. The Brandmeister servers route calls between repeaters and hotspots. Repeater book will usually tell you if a repeater is Brandmeister linked and what static talkgroups it has. Static talkgroups are talkgroups that are always linked however if someone is using a different talkgroup on the repeater or hotspot you will not hear traffic from the static talkgroups. After a set amount of time it will usually revert to the static talkgroup.
Talkgroups are group calls, think of them as chat rooms. Once you're connected to a talkgroup you can hear all conversations on that channel. Talkgroups are generally split up by location. 91 is Worldwide, Nationwide 3100 is North America, 3169 is Midwest, 3117 is Illinois and so on. There are lots of other talkgroups for different groups as well TGIF, The Guild, TAC 310. There are over 1,000 talkgroups available on Brandmeister. The Pi Star website has a nice list here.
Repeaters VS Hotspots
Once you have a hotspot properly setup there is little difference between using it vs a repeater. The main difference is that when on a repeater you have to keep a watch for other users and share the repeater. Here's a list of things to know.
- Repeaters use both time slots usually with different static talkgroups.
- Hotspots only use one time slot
- Hotspots can link to any talkgroup by keying it in the radio
- Repeaters usually have one slot or the other designated for dynamic group calls
- Both can have statically linked talkgroups
Just remember to be polite and practice good operating procedure and you'll be talking around the globe in no time. A few good places to start are
- 3100 USA Nationwide
- 91 Worldwide
- 310 TAC 310
Hope this helps you get going, 73s K9NPX