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= Ham Radio =
[[File:FEMA - 37931 - Red Cross volunteer at communications system in Texas.jpg|thumb|right|280px|When the grid fails, radio operators become the last information network]]
Your comprehensive guide to radio frequencies, protocols, and the tools to explore them.
== Ham Radio Protocols ==
== Ham Radio Protocols ==


Your comprehensive guide to radio frequencies, protocols, and the tools to explore them.
[[File:US Army 52421 Signal Corps Radio.jpg|thumb|right|250px|The lineage runs deep - Army Signal Corps, 1940s]]


=== GMRS (General Mobile Radio Service) ===
=== GMRS (General Mobile Radio Service) ===


**Frequency allocation:** 462-467 MHz, 22 channels total. Channels 1-7 and 15-22 allow up to 50W, channels 8-14 limited to 5W.
Frequency allocation: 462-467 MHz, 22 channels total. Channels 1-7 and 15-22 allow up to 50W, channels 8-14 limited to 5W.


**Repeater pairs:** Channels 15-22 use +5 MHz offset (input 467.550-467.725, output 462.550-462.725).
Repeater pairs: Channels 15-22 use +5 MHz offset (input 467.550-467.725, output 462.550-762.725).


**Licensing:** $35 FCC registration, no examination required, 10-year term covers immediate family.
Licensing: $35 FCC registration, no examination required, 10-year term covers immediate family.


**CTCSS/DCS:** Privacy codes prevent interference but don’t provide security - all transmissions remain receivable.
CTCSS/DCS: Privacy codes prevent interference but don't provide security - all transmissions remain receivable.


=== Amateur Radio Fundamentals ===
=== Amateur Radio Fundamentals ===


**2 meters (144-148 MHz):** Most popular VHF band. Repeater outputs 144-145 MHz, inputs 145-146 MHz with +600 kHz offset. Simplex operation on 146.52 MHz (national calling frequency).
[[File:Yaesu FT-857D.jpg|thumb|left|200px|Yaesu FT-857D - all bands, fits in a go bag]]


**70 centimeters (420-450 MHz):** UHF band with +5 MHz offset for repeaters. Regional variations exist - West Coast often uses -5 MHz.
2 meters (144-148 MHz): Most popular VHF band. Repeater outputs 144-145 MHz, inputs 145-146 MHz with +600 kHz offset. Simplex operation on 146.52 MHz (national calling frequency).


**6 meters (50-54 MHz):** “Magic band” with sporadic E propagation enabling 500+ mile contacts during openings.
70 centimeters (420-450 MHz): UHF band with +5 MHz offset for repeaters. Regional variations exist - West Coast often uses -5 MHz.


**License progression:** Technician (VHF/UHF privileges, limited HF), General (most HF bands), Amateur Extra (full privileges including exclusive subbands).
6 meters (50-54 MHz): "Magic band" with sporadic E propagation enabling 500+ mile contacts during openings.


**Exam structure:** 35 multiple choice questions, 74% passing score. No Morse code requirement since 2007.
License progression: Technician (VHF/UHF privileges, limited HF), General (most HF bands), Amateur Extra (full privileges including exclusive subbands).


=== Digital Protocols ===
Exam structure: 35 multiple choice questions, 74% passing score. No Morse code requirement since 2007.


**Packet radio:** AX.25 protocol standard, typically 1200 baud on 2m (145.01-145.09 MHz).
{{clear}}


**APRS:** 144.39 MHz North America primary frequency. Transmits position, weather, messages using unconnected protocol.
=== Mesh Networking ===
 
**Winlink:** Email over radio using Pactor, VARA, or packet modes. RMS (Radio Message Server) gateways connect to internet.
 
**DMR (Digital Mobile Radio):** Time-division multiple access, two talk paths per 12.5 kHz channel. Talk groups enable worldwide communication.
 
**D-STAR:** Digital voice with 6.25 kHz bandwidth, internet linking via reflectors.
 
**System Fusion:** Yaesu’s digital mode with analog fallback capability.


=== Mesh Networking ===
[[File:LoRa logo trademarked.svg|thumb|right|150px|LoRa - the protocol that lets you ping friends across valleys]]


**Meshtastic:** LoRa modulation on 915 MHz (US), 868 MHz (EU), 433 MHz (Asia). Spreading factors SF7-SF12, higher SF = longer range but slower data rate. AES-256 encryption with rotating keys.
'''Meshtastic:''' LoRa modulation on 915 MHz (US), 868 MHz (EU), 433 MHz (Asia). Spreading factors SF7-SF12, higher SF = longer range but slower data rate. AES-256 encryption with rotating keys.


**Hardware:** ESP32-based nodes, typical 1-10km range depending on terrain and antenna height.
Hardware: ESP32-based nodes, typical 1-10km range depending on terrain and antenna height.


**Protocols:** Position sharing, text messaging, sensor data relay through multi-hop mesh.
Protocols: Position sharing, text messaging, sensor data relay through multi-hop mesh.


**AREDN (Amateur Radio Emergency Data Network):** High-speed mesh on 2.4/5.8 GHz using modified OpenWrt firmware. IP networking over amateur frequencies enables video, VoIP, file sharing.
'''AREDN (Amateur Radio Emergency Data Network):''' High-speed mesh on 2.4/5.8 GHz using modified OpenWrt firmware. IP networking over amateur frequencies enables video, VoIP, file sharing.


**Equipment:** Ubiquiti devices flashed with AREDN firmware. Bandwidth up to 150 Mbps depending on modulation and channel width.
Equipment: Ubiquiti devices flashed with AREDN firmware. Bandwidth up to 150 Mbps depending on modulation and channel width.


=== ATAK Integration ===
=== ATAK Integration ===


**TAK (Team Awareness Kit):** Military-derived situational awareness platform using Cursor-on-Target (CoT) messages in XML format.
[[File:Cursor on Target XML Protocol.svg|thumb|right|200px|Cursor-on-Target - military SA goes civilian]]
 
**Data sources:** GPS positions, imagery, chat, file sharing.
 
**Radio integration:** APRS position feeds, voice coordination on amateur frequencies.
 
**Mesh compatibility:** Operates over any IP network including AREDN mesh nodes.
 
**Plugin architecture:** Supports various radios through TAK server or direct integration. Amateur radio provides backup when primary data links fail.
 
=== Software Defined Radio ===
 
**HackRF One:** 1 MHz - 6 GHz coverage, half-duplex operation. Sample rate up to 20 MSPS, 8-bit resolution.
 
**Software:** GNU Radio, SDR#, GQRX, Universal Radio Hacker.
 
**Applications:** Spectrum analysis, signal reverse engineering, protocol development, interference hunting.
 
**RTL-SDR:** $20-30 dongles covering 24-1700 MHz (with gaps). RTL2832U + R820T2 common chipset combination.
 
**Uses:** ADS-B aircraft tracking, ACARS decoding, trunked radio monitoring, ISM band analysis.
 
=== Flipper Zero Capabilities ===
 
**Sub-GHz radio:** 300-928 MHz coverage using CC1101 transceiver. ASK, FSK, GFSK, MSK modulations with configurable parameters.
 
**Applications:** Garage door analysis, weather station monitoring, ISM device research.
 
**Storage:** Raw recordings and protocol analysis for reverse engineering.
 
**Additional radios:** 125 kHz RFID, 13.56 MHz NFC, infrared transceiver.
 
**GPIO interface:** External radio modules and sensors. Open source firmware with active development community.
 
=== ADS-B Surveillance ===


**Frequency:** 1090 MHz, Mode S transponders broadcasting position, velocity, identification, status.
TAK (Team Awareness Kit): Military-derived situational awareness platform using Cursor-on-Target (CoT) messages in XML format.


**Range:** Line-of-sight, typically 100-250 miles with elevated antenna.
Data sources: GPS positions, imagery, chat, file sharing.


**Decoding:** dump1090 software with RTL-SDR hardware.
Radio integration: APRS position feeds, voice coordination on amateur frequencies.


**Integration:** Feeds to FlightRadar24, ADSBexchange for global tracking network.
Mesh compatibility: Operates over any IP network including AREDN mesh nodes.


**Military/sensitive aircraft:** Often operate with transponders disabled or on different frequencies.
Plugin architecture: Supports various radios through TAK server or direct integration. Amateur radio provides backup when primary data links fail.


**MLAT:** Multilateration using time-difference-of-arrival from multiple receivers enables tracking without GPS broadcasts.
== The Real Value ==


=== Programming Procedures ===
[[File:Shortwave Radio - kl.jpg|thumb|right|250px|When everything else is noise, the spectrum speaks truth]]


**TH-D3 offset programming:** Menu → Frequency → Offset Direction (+ or -) → Offset Frequency → Enter value → Store.
Radio isn't about the technology. It's about '''information independence'''. When networks fail, when infrastructure crumbles, when algorithms control what you see - radio remains. No servers. No accounts. No terms of service.


**Memory channels:** Menu → Memory → Channel number → Store current frequency/settings.
Just you, the ionosphere, and whoever else is listening.


**CTCSS:** Menu → Signaling → CTCSS → Tone frequency selection.
{{Navbox Technical}}


**Repeater directories:** RepeaterBook.com,​​​​​​​​​​​​​​​​
[[Category:Technical Systems]][[Category:Radio]][[Category:Emergency Communications]]

Latest revision as of 23:50, 7 December 2025

Ham Radio

File:FEMA - 37931 - Red Cross volunteer at communications system in Texas.jpg
When the grid fails, radio operators become the last information network

Your comprehensive guide to radio frequencies, protocols, and the tools to explore them.

Ham Radio Protocols

File:US Army 52421 Signal Corps Radio.jpg
The lineage runs deep - Army Signal Corps, 1940s

GMRS (General Mobile Radio Service)

Frequency allocation: 462-467 MHz, 22 channels total. Channels 1-7 and 15-22 allow up to 50W, channels 8-14 limited to 5W.

Repeater pairs: Channels 15-22 use +5 MHz offset (input 467.550-467.725, output 462.550-762.725).

Licensing: $35 FCC registration, no examination required, 10-year term covers immediate family.

CTCSS/DCS: Privacy codes prevent interference but don't provide security - all transmissions remain receivable.

Amateur Radio Fundamentals

File:Yaesu FT-857D.jpg
Yaesu FT-857D - all bands, fits in a go bag

2 meters (144-148 MHz): Most popular VHF band. Repeater outputs 144-145 MHz, inputs 145-146 MHz with +600 kHz offset. Simplex operation on 146.52 MHz (national calling frequency).

70 centimeters (420-450 MHz): UHF band with +5 MHz offset for repeaters. Regional variations exist - West Coast often uses -5 MHz.

6 meters (50-54 MHz): "Magic band" with sporadic E propagation enabling 500+ mile contacts during openings.

License progression: Technician (VHF/UHF privileges, limited HF), General (most HF bands), Amateur Extra (full privileges including exclusive subbands).

Exam structure: 35 multiple choice questions, 74% passing score. No Morse code requirement since 2007.

Template:Clear

Mesh Networking

File:LoRa logo trademarked.svg
LoRa - the protocol that lets you ping friends across valleys

Meshtastic: LoRa modulation on 915 MHz (US), 868 MHz (EU), 433 MHz (Asia). Spreading factors SF7-SF12, higher SF = longer range but slower data rate. AES-256 encryption with rotating keys.

Hardware: ESP32-based nodes, typical 1-10km range depending on terrain and antenna height.

Protocols: Position sharing, text messaging, sensor data relay through multi-hop mesh.

AREDN (Amateur Radio Emergency Data Network): High-speed mesh on 2.4/5.8 GHz using modified OpenWrt firmware. IP networking over amateur frequencies enables video, VoIP, file sharing.

Equipment: Ubiquiti devices flashed with AREDN firmware. Bandwidth up to 150 Mbps depending on modulation and channel width.

ATAK Integration

File:Cursor on Target XML Protocol.svg
Cursor-on-Target - military SA goes civilian

TAK (Team Awareness Kit): Military-derived situational awareness platform using Cursor-on-Target (CoT) messages in XML format.

Data sources: GPS positions, imagery, chat, file sharing.

Radio integration: APRS position feeds, voice coordination on amateur frequencies.

Mesh compatibility: Operates over any IP network including AREDN mesh nodes.

Plugin architecture: Supports various radios through TAK server or direct integration. Amateur radio provides backup when primary data links fail.

The Real Value

File:Shortwave Radio - kl.jpg
When everything else is noise, the spectrum speaks truth

Radio isn't about the technology. It's about information independence. When networks fail, when infrastructure crumbles, when algorithms control what you see - radio remains. No servers. No accounts. No terms of service.

Just you, the ionosphere, and whoever else is listening.


⚡ Technical
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