An RTL-SDR dongle has a maximum usable bandwidth of about 2.4 MHz which most often isn't enough to capture an entire trunking system that may be spread out over a larger bandwidth. In order to get around this limitation Luke Brendt has been using three RTL-SDR dongles together to capture a trunking system in his area which…
Episode 7 – Monitoring DMR & NXDN with 1 SDR – Frugal Radio
Data Calls, what can I do with them?
Beginners Guide of RTL SDR (Software Defined Radio) on Kali Linux - Infocerts LLP
Triple Threat RTL-SDR System Reads Trunked Radio
trunking
Using multiple RTL-SDR dongles with the same antenna : r/RTLSDR
trunked radio
SDR Primer Part 2: Exploring the world of SDRs for $200 or less
Nooelec - Nooelec NESDR Mini 2 USB RTL-SDR and ADS-B Receiver Set, RTL2832U and R820T2 Tuner, w/ Antenna. MCX Input. Low-Cost Software Defined Radio Compatible with Many SDR Software Packages, ESD-Safe
Dual SDR Channel Lock to Control Channel Frequency
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Setting Up A Police Scanner With An RTL-SDR
Trunking Police Scanning With SDRTrunk