DMR radio
Digital Mobile Radio puts two voice conversations on one 12.5 kHz channel, and internet-linked networks like BrandMeister let a handheld in Akron talk to a hotspot in Australia. Here is how it works, how to get on, and where Ohio hangs out.
How it works
The short version, for anyone coming from analog FM.
Two timeslots
2per channel
TDMA splits each 12.5 kHz channel into Timeslot 1 and Timeslot 2, so one repeater carries two separate conversations.
Talkgroups
TGnot tones
Instead of PL tones you pick a talkgroup: a numbered channel on the network that everyone keyed to it can hear.
Color code
CC0 to 15
The digital stand-in for a PL tone. Your radio has to match the repeater’s color code to get in.
Voice codec
AMBE+2
Voice is digitized with the AMBE vocoder. Audio stays clear until the signal drops out, then it is gone, not noisy.
Getting on the air
You need a Technician license or higher. Start here if you do not have one yet.
- Get a DMR IDRegister free at RadioID.net with your callsign. Ohio IDs start with 3139.
- Pick a radioAny DMR Tier II handheld or mobile works. Dual-band models cover both 2 m and 70 cm repeaters.
- Build a codeplugThe radio’s channel file: frequency, color code, timeslot and talkgroup for each channel. Start from a local club’s codeplug if one exists.
- Find a repeater or hotspotUse a nearby DMR repeater, or a small hotspot on your home internet if none are in range.
- Test with ParrotMake a private call to 9990 on BrandMeister. It plays your transmission back so you can hear your audio.
- Listen firstKey up on Ohio Statewide 3139 or Worldwide 91, give your callsign, and keep it short. A pause between overs lets others break in.
Talkgroups to know
BrandMeister talkgroups. Tap one to copy the number for your codeplug.
Repeaters set their own static talkgroups and timeslots. Check with the repeater owner before you program.
Tools and live activity
Everything opens in a new tab.
BrandMeister Last Heard
Live
Who is keyed up on BrandMeister right now, and on which talkgroup.
RadioID.net
ID
Register for your DMR ID or look up someone else’s.
Repeaters near Akron
Find
RepeaterBook’s list for the Akron area. Filter by DMR to see digital machines.
Ohio DMR repeaters
OH
Area DMR repeater information from Ohio Hams.
Pi-Star hotspots
Spot
Free software that turns a Raspberry Pi and a small modem into a personal DMR hotspot.
Radio & digital
More
Propagation, FT8 frequencies, PSKReporter and the rest of the digital modes.
Talkgroup numbers are from the BrandMeister network; 3139 is the Ohio statewide talkgroup per the ARRL Ohio Section. Networks change, so confirm with your repeater owner. 73 de K8SCS.
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