🌐 Summary
3 MHz (range 3.5–4 MHz) is part of 80m Amateur Band within the HF spectrum.
Quick summary: 3 MHz is allocated to 80 Meter Amateur Band. Used for amateur radio communications. Applications include ham radio dx, contests, regional nets, digital modes. Operated by amateur radio enthusiasts. Technology: SSB, CW, digital (FT8, PSK31). Amateur radio license required.
Primary use: Amateur radio communications
Common applications: Ham radio DX, contests, regional nets, digital modes
Technology: SSB, CW, digital (FT8, PSK31)
Quick Facts The 80-meter amateur band includes this frequency. During nighttime, signals here can bounce off the ionosphere and travel thousands of miles. Hams use it for long-distance contacts.
Source: 47 CFR Part 97
3.5-3.6 CW/data; 3.6-4.0 phone/CW
📶 Band & Identity
| Field | Value |
|---|---|
| Frequency (MHz) | 3 |
| Lower Band Edge (MHz) | 3.5 |
| Upper Band Edge (MHz) | 4 |
| Band Name | 80m Amateur Band |
| Spectrum Block | HF |
| Popular Name | 80/75 Meter Band |
| Allocation Status | Active |
| Exclusive / Shared | Yes |
| Protected Services | Amateur radio (FCC Part 97 protections) |
| Related Frequencies | -2-8 MHz band |
📜 FCC Rules & Licensing
| Field | Value |
|---|---|
| FCC Service Type | AMATEUR |
| FCC Secondary Services | See primary allocation |
| FCC Part Number | Part 97 |
| FCC Rule Section | 47 CFR 97.301 |
| License Required | Yes |
| License Type | Amateur radio license |
| License Fee Type | Application fee |
| Annual Regulatory Fee | Varies |
| License Term (Years) | 10 |
| Renewal Expectancy | High |
| Auction History | Not auctioned (comparative licensing) |
| Refarming Status | Stable |
| Geographic Restrictions | Border coordination may apply near Canada/Mexico |
| Quiet Zones | No |
| Coordination Required | Frequency coordination required |
| Warnings / Notices | Unauthorized transmission is illegal and subject to FCC enforcement |
⚙️ RF & Technical
| Field | Value |
|---|---|
| Technology | SSB, CW, digital (FT8, PSK31) |
| Modulation | SSB (J3E), CW (A1A), digital |
| Typical Bandwidth | 3-6 kHz |
| Transmitter Type | Amateur HF transceivers |
| Receiver Type | HF amateur receivers |
| Typical Power (W) | 10-1500 |
| Maximum Power Limit | 1500 W PEP |
| ERP Limit | 1500W PEP (transmitter power, not ERP) |
| Antenna Height Limits | Varies |
| Antenna (Quarter-Wave) | 78.00 ft (2377.4 cm) |
| Duplex Mode | Simplex |
| Paired Frequency | Not paired (simplex) |
| Channelization | Variable |
| Guard Bands (kHz) | Varies |
| Emission Designator | Varies |
| Emission Mask | FCC standards |
| Part 15 Device Limits | Not applicable (licensed spectrum) |
| Spread Spectrum Allowed | No |
| Frequency Hopping Allowed | No |
| Power Control Required | No |
🌤️ Propagation
| Field | Value |
|---|---|
| Propagation Mode | Ionospheric skip, ground wave |
| Typical Range (Miles) | 500-2000+ |
| Day vs Night Differences | Primarily nighttime DX |
| Atmospheric Effects | Strong ionospheric propagation |
| Interference Concerns | Standard adjacent channel and co-channel interference |
🛡️ Ecosystem
| Field | Value |
|---|---|
| Primary Use | Amateur radio communications |
| Common Applications | Ham radio DX, contests, regional nets, digital modes |
| Can You Listen? | Yes – amateur radio (public communications) |
| Encryption Status | Not encrypted (prohibited by FCC rules for amateur radio) |
| Popular Radio Models | Icom IC-7300, Yaesu FT-991A, Yaesu FT-450D, Kenwood TS-590SG, Elecraft K3/K4, Xiegu G90, RTL-SDR Blog V3 |
| License Holders | Licensed amateur radio operators (~750,000 USA) |
| Major Operators | Individual ham operators |
| Government Use | No |
| Military Use | No |
| Public Safety | No |
| Critical Infrastructure | No |
| Amateur Radio | Yes |
| ISM Band | No |
| Unlicensed Operation | No |
| Consumer Equipment | Yes |
| Common Devices | HF transceivers (Icom IC-7300, Yaesu FT-991A, Elecraft K3, Xiegu G90), SDR receivers (Airspy HF+, SDRplay RSPdx), antenna tuners |
| Receive Only | No |
| Radio Astronomy | No |
| Satellite Downlink | No |
| Passive Service | No |
| Spectrum Occupancy (Estimated) | 40-70% |
| Urban vs Rural | Varies by location |
| Deployment Density | Moderate |
🌎 International
| Field | Value |
|---|---|
| ITU Region 2 Allocation | AMATEUR |
| International Harmonization | Yes |
| Cross-Border Coordination | No |
| Year Allocated | 1927 |
| Legacy Uses | Historical allocations stable |
| Future Plans | Stable |
🧾 Compliance
| Field | Value |
|---|---|
| FCC Certification Required | Yes |
| Equipment Authorization Type | Certification (amateur equipment) |
| FCC ID Required | No |
| Compliance Testing | FCC equipment authorization required |