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Frequency Cheatsheet

Key bands within HackRF range (1 MHz – 6 GHz) · modulation · antenna · typical signals

Antenna: ③ Telescopic ⑥ Magmount loop ⑦ Magmount coil ④ Rubber duck stub
Quarter-wave formula: optimal antenna length (cm) = 7500 ÷ frequency (MHz). Extend the telescopic antenna to match before tuning a new band.

VLF — AM Broadcast

BandFrequencyModeAntennaWhat you'll hear
AM Broadcast 530 kHz – 1.7 MHz AM ③ Telescopic News, talk, music (long range at night)
Shortwave 3 – 30 MHz AM / SSB ③ Telescopic International broadcasters, ham radio, time signals (WWV 10/15/20 MHz)

VHF

BandFrequencyModeAntennaWhat you'll hear
FM Broadcast 87.5 – 108 MHz WFM ③ 75 cm Music, news, talk. Strongest signals you'll receive.
Airband 118 – 137 MHz AM ③ 63 cm ATC, ground control, ATIS, approach. Aircraft in range.
NOAA satellites 137.5 / 137.9125 MHz WFM (APT) ⑥ Magmount loop Weather satellite imagery (requires SatDump, overhead passes only).
2m Ham radio 144 – 146 MHz NFM ⑥ Magmount loop Local repeaters, simplex QSOs, APRS at 144.800 MHz.
Marine VHF 156 – 162 MHz NFM ⑥ Magmount loop Ships, ports, bridges. Ch16 (156.800 MHz) = distress/calling.

UHF

BandFrequencyModeAntennaWhat you'll hear / decode
PMR446 446.0 – 446.2 MHz NFM ⑥ Magmount loop Unlicensed walkie-talkies — events, construction, security.
ISM 433 MHz 433.05 – 434.79 MHz OOK / FSK ⑥ Magmount loop Doorbells, weather stations, remote controls, car key fobs.
ISM 868 MHz 863 – 870 MHz FSK / LoRa ⑥ Magmount loop LoRaWAN gateways, alarm systems, smart meters (EU).
GSM / LTE 700 – 900 MHz, 1800 MHz — ⑦ Magmount coil Mobile network cell towers (receive only, no decryption).

L-Band

BandFrequencyModeAntennaWhat you'll hear / decode
ADS-B 1090 MHz PPM ④ Rubber duck Aircraft position, altitude, squawk. Decode with dump1090 or FlightAware.
GPS L1 1575.42 MHz BPSK ④ Rubber duck Satellite navigation signals (receive only — active GPS patch antenna improves this).
ACARS 129.125 / 136.900 MHz AM (VDL) ③ Telescopic Aircraft datalink messages — position, weather, ATIS requests.
Inmarsat 1525 – 1559 MHz BPSK ④ Rubber duck Maritime/aviation satellite comms. Decode with Jaero.

S-Band & above

BandFrequencyModeAntennaWhat you'll decode
WiFi 2.4 GHz 2400 – 2484 MHz OFDM ⑦ Magmount coil WiFi beacons visible in spectrum. Cannot decode — use dedicated WiFi hardware.
Bluetooth 2402 – 2480 MHz FHSS ⑦ Magmount coil Frequency-hopping — bursts visible in waterfall. Cannot decode with HackRF alone.
WiFi 5 GHz 5150 – 5850 MHz OFDM ④ Rubber duck At the edge of HackRF's range. Beacon frames visible in spectrum only.
HackRF limitation at high frequencies: Above ~3 GHz receive sensitivity drops significantly. An external LNA (⑤) helps in the 1–3 GHz range. Above 3 GHz, results depend heavily on antenna placement and proximity to the source.