Frequency
27 MHz
Range
27β27 MHz
Band Group
HF (<30 MHz)
π Summary
27 MHz: Maritime, aeronautical, amateur, broadcast (varies); CB (personal radio); CB 11β―m; CB radios, trucking, hobbyist
CB radio 26.965β27.405 MHz (40 channels); ISM center frequency at 27.12 MHz widely used industrially.
π Explore the full RF Spectrum database
π‘ Band & Geometry key
| Field | Value |
|---|---|
| Wavelength (m) | 11.111 |
| Waveforms | AM, SSB, CW |
| Antenna Form Factor (Typical) | ΒΌ-wave β 278 cm |
| Band Family | Amateur/CB |
| Band | CB (11β―m) / VHF Low |
| Primary Common Name | Citizens Band (CB) |
| FSPL @ 1 km [dB] | 61.06727528318 |
| FSPL @ 10 km [dB] | 81.06727528318 |
| Fresnel Radius @ 1 km (m) | 52.703081644386 |
| Band Group | HF (<30 MHz) |
| Tax Band Family | HF |
| Tax Band Class | HF (3β30 MHz) |
π§© Applications & Usage
| Field | Value |
|---|---|
| Primary Application | Maritime, aeronautical, amateur, broadcast (varies) |
| Lower Neighbor Use | HF / MF Band |
| Upper Neighbor Use | HF / MF Band |
| Typical Services Devices | CB 11β―m |
| Market Common Devices | CB radios, trucking, hobbyist |
| Refarming Use | No |
| Device Ecosystem Size | Low (<100 models) |
| Device Hotspots (MHz) | 27 |
| Device Category | CB Radios |
| Typical Use Cases | – |
| Modulation (Device) | Varies by device |
| Channel Width (Device) [kHz] | Varies |
| Device Region Profiles | Varies by country / allocation |
| Per-Region EIRP Or Duty (Device) | Varies by regulation |
| Allocation Relevance (Device) | Medium |
| Adjacent-Band Collision Risks (Device) | LowβModerate |
| Example Devices Or Skus | CB Radio, Walkie Talkie |
| Common Protocols | VHF AM Voice (8.33 kHz); VDL Mode 2 (select freqs); Marine VHF Voice; DSC (CH70); AIS (162 MHz); Amateur (various modes) |
ποΈ Notes
| Field | Value |
|---|---|
| Receiver Selectivity Notes | β₯40 dB @ Β±2.4 kHz |
| Interference Notes | Channelized; low power limits; adjacent to ISM toys/RC in some regions |
| Compatibility Risk Notes | – |
| Notes | CB radio 26.965β27.405 MHz (40 channels); ISM center frequency at 27.12 MHz widely used industrially. |
| Propagation Notes | Strong coverage, good indoor penetration |
βοΈ Technical Rules
| Field | Value |
|---|---|
| Lower Band Frequency Limit | 27 |
| Upper Band Frequency Limit | 27 |
| EIRP Indoor Limits | N/A (licensed; verify national rules) |
| EIRP Outdoor Limits | CB: per admin caps; ISM @27.12 low EIRP |
| PSD Limit | β |
| Emission Mask Class | CB/ISM |
| Guardband Minimum [kHz] | 10 |
| Typical Bandwidths | 8β10 kHz |
| Autocalculated Bandlimits | No |
| Typical Bandwidths (Estimated) | 8β10 kHz |
| Max EIRP [dBm] | Varies by regulation |
| Power Source Or Duty Profile (Typical) | – |
| Channelization Plan | – |
| Channelization | AM, SSB, CW |
| Guard Band Requirement | – |
| OOB Emission Limit [dBm/MHz] | -13 (baseline) |
| Spurious Emission Limit (dBm) | -30 (baseline) |
| RX Blocking Min [dBm] | -15 (planning) |
| Duplexing | Half-duplex |
| Duplexing Information | Simplex |
| Uplink Pairing | – |
| Downlink Pairing | – |
| Paired Band Info | – |
| Max EIRP [dBm] | – |
| Channelization Block Size | 10 kHz channels |
| 3GPP Band Number | |
| Example 3GPP Bands | – |
| LTE Uplink Bands | – |
| LTE Downlink Bands | – |
| NR Uplink Bands | – |
| NR Downlink Bands | – |
| Guard Bands | 2 kHz spacing |
| Protocol Or Standard | – |
π Country Overrides
| Field | Value |
|---|---|
| Post Status | publish |
| Tax Service Category | Other / Various |
| Tax License Type | License-Exempt |
| Tax Regions | Global / Varies |
| ITU Region 1 | Fixed, Mobile |
| ITU Region 2 | Fixed, Mobile |
| ITU Region 3 | Fixed, Mobile |
| License Type | License-exempt personal radio (CB) β national rules |
| Primary Application | Maritime, aeronautical, amateur, broadcast (varies) |
| Primary Services | CB (personal radio) |
| Spurious Emission [dBm] | -30 (baseline) |
| Lower Neighbor Use | HF / MF Band |
| Upper Neighbor Use | HF / MF Band |
| Licensing Model | Licensed (varies by country) |
| Typical Services Devices | CB 11β―m |
| US FCC Alloc | -β |
| CA IC Alloc | -β |
| UK Ofcom Alloc | -β |
| US Ref | – |
| Typical Bandwidths | 8β10 kHz |
| Market Licensing Model | License-exempt (varies) |
| Market Common Devices | CB radios, trucking, hobbyist |
| Fresnel Radius (1st, 1 km) [m] | 52.703081644386 |
| Typical Bandwidths (Estimated) | 8β10 kHz |
| Auction Status | – |
| Refarming Use | No |
| Typical Site Spacing km | β / β |
| Device Ecosystem Size | Low (<100 models) |
| Traffic Load Share | Coverage-heavy, low capacity share |
| Device Hotspots (MHz) | 27 |
| Device Category | CB Radios |
| Typical Use Cases | – |
| Typical Center Frequencies [MHz] | – |
| Rule Part (Fcc Or Region) | – |
| Modulation (Device) | Varies by device |
| Channel Width (Device) [kHz] | Varies |
| Device Region Profiles | Varies by country / allocation |
| Per-Region EIRP Or Duty (Device) | Varies by regulation |
| Allocation Relevance (Device) | Medium |
| Adjacent-Band Collision Risks (Device) | LowβModerate |
| Example Devices Or Skus | CB Radio, Walkie Talkie |
| Antenna Form Factor (Typical) | ΒΌ-wave β 278 cm |
| Power Source Or Duty Profile (Typical) | – |
π‘οΈ Regulatory & Neighbors
| Field | Value |
|---|---|
| Lower Band Frequency Limit | 27 |
| Upper Band Frequency Limit | 27 |
| Rx Blocking Min dBm | -15 (planning) |
| Lower Neighbor Use | HF / MF Band |
| Upper Neighbor Use | HF / MF Band |
| Lower Neighbor Band | HF / MF Band |
| Lower Neighbor Range | 1.000β26.000 MHz |
| Upper Neighbor Label | HF / MF Band |
| Upper Neighbor Range | 28.000β30.000 MHz |
| Adjacent-Band Collision Risks (Device) | LowβModerate |
| Real-World Range (Indoor/Outdoor) | – |
| US FCC Alloc | — |
| CA IC Alloc | — |
| UK Ofcom Alloc | — |
| Regulatory References | US: -; CA: -; UK: – |
| Global Harmonization | Global |
| Crossborder Coordination | High |
| Sharing Mechanism | – |
| Auction Status | – |
| Guard Or Pair | – |
π Market & Measurements
| Field | Value |
|---|---|
| Noise Floor | High atmospheric noise in HF |
| Interference Cases | Atmospheric & manβmade |
| Lower Neighbor Range | 1.000β26.000 MHz |
| Upper Neighbor Range | 28.000β30.000 MHz |
| Interference Notes | Channelized; low power limits; adjacent to ISM toys/RC in some regions |
| Market Licensing Model | License-exempt (varies) |
| Market Commercial Value | Low |
| Market Common Devices | CB radios, trucking, hobbyist |
| Market Deployment Density | Low to medium rural |
| Noise Floor (Estimated) | High atmospheric noise in HF |
| Market Commercial Value (Estimated) | Low |
| Ecosystem Maturity | Emerging |
| Indoor Penetration | Good |
| Known Interference | No major interference issues noted |
| Device Ecosystem Size | Low (<100 models) |
| Real-World Range (Indoor/Outdoor) | – |
| Antenna Form Factor (Typical) | ΒΌ-wave β 278 cm |
| Ecosystem Maturity | Emerging |
| Device Ecosystem Size | Low (<100 models) |
| Chipset Availability | Ham radio equipment vendors |
| Operator Deployments | Individual operators worldwide |
| Technology Generations Deployed | Amateur voice/data modes |
| Roaming Support | No |
| Traffic Load Share | Coverage-heavy, low capacity share |
| Indoor Penetration | Good |
| Known Interference | No major interference issues noted |
| Occupancy | Varies by region/time |
| Occupancy Bucket Pct | 10β30% |
| Latency Profile | – |
| Common Channels Or Profiles | – |
| Security Features | – |
| Lbt Or Fhss Requirement | – |
| Popularity (Installed Base) | – |
| Coexistence Tips | – |
| Latency Class | – |
| Device Hotspots (Scoped && Tagged) | β |