📻 Comms & Radio

When the internet is cut or throttled in Cuba, radio and off-grid tools still work. This is a public reference: what to tune a radio to, which Cuban government signals can be monitored, and the established, openly-documented tools people use to keep communicating through shutdowns.

Read first — this carries real risk. Listening to radio is passive and generally low-risk. Transmitting on unauthorised frequencies, or holding unlicensed radio or mesh hardware, can be illegal and dangerous under the Cuban regime: transmissions can be direction-found, and possession alone can bring consequences. International rules also forbid encryption on amateur bands — ham radio is not a private channel. Nothing here promises safety or anonymity; it is public information so people can make their own informed choices.

Radio you can hear in Cuba

An ordinary AM/FM radio reaches mediumwave (AM) and FM; a shortwave (HF) radio or many cheap handheld receivers reach the shortwave bands. Nothing here needs the internet. Frequencies and times are quoted from public sources but can change — a shortwave schedule database (short-wave.info, HFCC) has the current list.

Radio Martí (US-funded, Spanish, aimed at Cuba)

Status is politically volatile: a March 2025 order dismantled the Office of Cuba Broadcasting, staff were recalled days later, and shortwave resumed 27 Jun 2025. Cuba jams it. Verify before relying on it.

FrequencyWhat it isSource
11860 · 13605 kHz SW / HFMon–Fri 14:00–22:00 UTC (transmitter Greenville, North Carolina). Reported audible across the Americas.SWLing Post · short-wave.info
1180 kHz AM / MWLong-standing mediumwave outlet from Marathon, Florida — an ordinary AM radio reaches it. Jammed.Wikipedia — Radio y TV Martí

Other Spanish shortwave reaching the Americas

FrequencyWhat it isSource
(seasonal) SW / HFRadio Exterior de España broadcasts in Spanish toward the Americas; exact kHz change with the seasonal HFCC schedule — read the current entry from a shortwave schedule database.short-wave.info · Wikipedia

Cuban government signals (monitor)

Signals that originate from Cuba and are logged by public radio-hobbyist monitoring communities. Listening is passive OSINT.

HM01 — the "Cuban lady" numbers station

Public monitors (Priyom.org) attribute it to Cuban intelligence (DGI): a Spanish female voice reads five-digit groups, then digital data is sent. NOTE: listed as hibernated — off air since a transmitter failure in Aug 2024. Shown as documented OSINT, not a live signal.

FrequencyWhat it isSource
9155 · 9330 · 10345 · 11435 · 11530 · 11635 kHz SW / HFSix of sixteen documented channels; full set spans 9065–17480 kHz. Two airings/hour (on the hour and half-past), roughly 16:00→10:00 UTC.Priyom.org · HFUnderground

Ham & scanner bands (handheld radios)

A common handheld like a Baofeng UV-5R covers VHF 136–174 MHz and UHF 400–520 MHz. These are the internationally standard band edges and calling frequencies; local use varies. Transmitting on these bands is legal only for licensed operators.

Cuban amateur radio

FrequencyWhat it isSource
CO · CM · CL · T4 PREFIXCuba's ITU amateur prefixes. Class sets power: 1st class CO (≤2000 W), 2nd CM (≤100 W), 3rd CL (≤10 W); T4/…0 are special/event calls.ARRL · Wikipedia (ITU prefix)
3720 · 3740 · 7110 · 7120 kHz HFFederación de Radioaficionados de Cuba (FRC) Emergency National Net. A ~65-station repeater network also exists; 2 m is the busiest band nationally.ARRL · IARU Region 2

Standard calling frequencies & HF bands (ITU Region 2, the Americas)

FrequencyWhat it isSource
146.520 MHz VHF 2 mStandard simplex calling frequency, 2-metre band — within a Baofeng's VHF range.RadioReference
446.000 MHz UHF 70 cmStandard simplex calling frequency, 70-centimetre band — within a Baofeng's UHF range.RadioReference
7.000–7.300 · 14.000–14.350 MHz HF 40/20 mThe busy 40 m and 20 m amateur HF bands (Region 2 edges). Full set: 160/80/40/30/20/17/15/12/10 m.IARU Region 2 band plan

Marine & aviation (regional)

Internationally standardised distress, calling and airband frequencies used across the region. These tie directly to the maritime and air intelligence on this platform.

Marine

FrequencyWhat it isSource
156.800 MHz VHF Ch 16International distress, safety and calling channel; monitored 24 h by many coast guards.US Coast Guard NavCen
156.300 · 156.650 · 156.525 MHz VHFCh 06 intership safety/SAR · Ch 13 navigation safety (bridge-to-bridge) · Ch 70 digital DSC distress (no voice).US Coast Guard NavCen
2182 kHz MF / HFTraditional MF voice distress/calling (paired with 2187.5 kHz DSC). Continuous watch is reduced under GMDSS — a standard designation, not a guaranteed monitored channel.Wikipedia — distress frequency

Aviation

FrequencyWhat it isSource
121.500 MHz VHFInternational Air Distress ("guard") — the civil aircraft emergency frequency.Wikipedia — distress frequency
118–137 MHz VHF airband (AM)Civil air-to-ground voice. A scanner covering this range can hear aircraft overhead.Wikipedia — distress frequency

Keeping in touch without the internet

Established, open tools that pass messages phone-to-phone or over small radios, with no cell tower or internet in the middle. Named for reference; each has real limits, listed plainly.

Briar encrypted messaging

Open-source encrypted messenger for activists and journalists; no central server, no phone number. Online it syncs over Tor (hiding who talks to whom); offline it syncs phone-to-phone over Bluetooth or Wi-Fi. Contacts are added by scanning each other's QR code.

Needs: two Android phones with BriarLimit: offline reach is only Bluetooth/Wi-Fi range (tens of metres); Android-first.
briarproject.org
Meshtastic (LoRa) radio mesh

Open firmware for cheap LoRa radio nodes that form a self-healing mesh: text hops node-to-node with no internet, cell service or servers. LoRa reaches several kilometres at very low power. Runs on licence-free bands (915 MHz in the Americas) and encrypts channels with AES-256.

Needs: a LoRa node per person/site + a phoneLimit: text and location only; low bandwidth; range collapses in dense terrain/buildings.
meshtastic.org
Bridgefy Bluetooth mesh · caution

A Bluetooth mesh app marketed for protests that relays messages phone-to-phone with no internet. CAUTION: a 2020 academic analysis ("Breaking Bridgefy") found user tracking, no real confidentiality or authenticity, man-in-the-middle and impersonation, and that one crafted message could down the whole mesh. Listed as a documented example WITH its weaknesses, not a recommendation.

Needs: phones with the appLimit: documented security weaknesses — do not treat as private or reliable.
Breaking Bridgefy (IACR 2021/214)
Offline Wi-Fi boxes local hotspot + content

A small self-contained box (e.g. a Raspberry Pi) broadcasts its own Wi-Fi so nearby phones connect and, via a web page, share files, chat and read pre-loaded content — no internet needed. The PirateBox/LibraryBox lineage pioneered this; disaster.radio adds solar LoRa links between boxes.

Needs: a small computer + power (solar works)Limit: local Wi-Fi range only; the original projects are largely archived (Meshtastic/Reticulum are the living successors).
PirateBox · LibraryBox · disaster.radio

Cuba has done this before

SNET — the Havana Street Network. A large volunteer-built community LAN in Havana — homes linked by cables, Wi-Fi antennas and hidden nodes for gaming, forums and file-sharing, entirely offline from the global internet, reportedly reaching ~100,000 IP addresses at its peak. New telecom rules effective 29 Aug 2019 banned its equipment; the state moved its users onto the government's Joven Club network, ending the independent one. Proof this can work at city scale with ordinary gear. Rest of World · WLRN

El Paquete Semanal — the weekly sneakernet. Cuba's hand-delivered offline internet: a curated ~1 TB collection of shows, films, news sites, software and ads compiled weekly and moved across the island on hard drives and USB sticks, copied door-to-door for about US$1–3. Running since ~2008, it became the main media source for millions — a working model of resilient offline content distribution. Wikipedia · CBC News

The community-mesh idea

A resilient neighbourhood network can be built from the public building blocks above: small low-power computers or LoRa radios placed within range of each other, each offering local Wi-Fi or Bluetooth that nearby phones join, relaying messages hop by hop so no central tower or internet is needed. SNET showed this can work at city scale in Havana with ordinary gear. Solar power keeps a node running through blackouts.

This describes publicly known technology, not a build kit or an operational plan. Anyone deploying radio hardware under the regime should weigh the legal and physical risk in the notice above; a hidden network is not automatically a safe one.

Reputable safety guidance

Access Now — #KeepItOn. A global coalition of 345+ organisations that documents and fights internet shutdowns — a first stop for shutdown context and advocacy. accessnow.org

EFF — Surveillance Self-Defense. Plain-language how-to guides on secure communication, security planning, and circumventing censorship, from the Electronic Frontier Foundation. ssd.eff.org

Amnesty International — digital security. Amnesty International publishes digital-security and human-rights-defender guidance. amnesty.org