Goal: Learn SDR fundamentals, decode DMR signals, and explore broader digital radio applications.
Stage 1: Foundation – Getting Started with SDR
Duration: 1–2 days
What You’ll Learn:
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What SDR is
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How to set up an SDR dongle
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How to listen to analog radio (FM, NOAA, etc.)
Tasks:
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Buy an RTL-SDR V3 dongle
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~ $30 USD at RTL-SDR (https://www.rtl-sdr.com/store/)
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Install SDR# (SDRSharp)
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Follow this: Quick Start Guide
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Tune into FM broadcast and NOAA weather
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Learn to adjust gain, squelch, and frequency
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Watch:
Stage 2: DMR Monitoring with SDR
Duration: 2–5 days
What You’ll Learn:
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How to decode DMR voice/data transmissions
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What Talkgroups, Color Codes, and Time Slots mean
Tasks:
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Install VB-Cable (virtual audio routing) (https://vb-audio.com/Cable/)
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Install DSD+ or DSD+ Fast Lane (https://www.dsdplus.com/)
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Pipe audio from SDR# → DSD+
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Find DMR frequencies near you:
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Use scanner data or repeater maps
Learn:
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DMR basics: CC = Color Code, TS = Timeslot, TG = Talkgroup
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Watch spectrum to spot active DMR bursts
Stage 3: Expand Your Capabilities
Duration: 1–2 weeks
What You’ll Learn:
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Tracking trunked radio systems
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Monitoring multiple channels
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Recording and logging traffic
Tools:
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DSD+ Fast Lane with
FMP24.exe -
Unitrunker (for trunking analysis) (https://unitrunker.com/)
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SDRTrunk (Java-based, all-in-one trunked system monitor) (https://github.com/DSheirer/sdrtrunk)
Explore:
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Municipal/public safety systems (if unencrypted)
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Commercial trunked systems (e.g., business DMR Tier III)
Stage 4: Deep Dive (Optional)
Duration: Long-term (ongoing)
What You’ll Learn:
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SDR at the software development level
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Transmitting with advanced SDRs (HackRF, LimeSDR)
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Creating digital decoders with GNU Radio
Projects:
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Build a DMR decoder in GNU Radio
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Decode satellite images (NOAA, Meteor-M2)
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Contribute to open-source SDR tools