Bands and Modes
Radio frequencies are divided into bands — ranges of frequencies set aside for amateur use. Different bands behave differently: some carry across town, some across the planet. The way your voice (or data) is encoded onto the radio wave is the mode.
The bands, in plain language
Frequencies are measured in MHz (megahertz — millions of cycles per second). Hams name bands by wavelength: the 2-meter band is around 144 MHz, because the radio wave there is about 2 meters long. Lower frequency = longer wavelength = generally farther reach, with more dependence on atmospheric conditions.
The main amateur bands (US allocations):
| Band | Frequency range | Character |
|---|---|---|
| 6 m | 50–54 MHz | "Magic band" — usually local, occasionally worldwide when conditions align |
| 2 m | 144–148 MHz | The workhorse: repeaters, local chat, emergency nets |
| 70 cm | 420–450 MHz | Like 2 m but shorter range; great for cities, handhelds |
| 10 m | 28.0–29.7 MHz | Worldwide when the sun cooperates; dead quiet otherwise |
| 20 m | 14.0–14.35 MHz | The classic long-distance band |
| 40 m | 7.0–7.3 MHz | Reliable day and night, regional to worldwide |
| 80 m | 3.5–4.0 MHz | Nighttime regional workhorse |
VHF (Very High Frequency, 30–300 MHz) and UHF (Ultra High Frequency, 300–3000 MHz) are essentially line-of-sight: your signal goes as far as the horizon, plus a bit. That's why repeaters on tall towers matter so much (Chapter 5). HF (High Frequency, 3–30 MHz) can bounce off the ionosphere and travel thousands of miles — when conditions allow.
Modes: SSB vs. FM
- FM (Frequency Modulation) — the same idea as FM broadcast radio. Clear, noise-resistant, easy. This is what nearly all VHF/UHF repeater and handheld talking uses.
- SSB (Single Sideband) — a more efficient voice mode that squeezes more distance out of less power. Standard for HF voice. Sounds a bit like Donald Duck if your receiver isn't tuned right — that's normal, just adjust.
- CW — Morse code. Still the most efficient human mode of all, and beloved by enthusiasts. Optional since 2007.
- Digital modes — computers encoding data as audio tones (Chapter 10 covers FT8).
Beginners live in FM on 2 m and 70 cm. It's simple, social, and works with the cheapest radios.
What a Technician can use
A Technician license gives you all amateur privileges above 30 MHz — that's 6 m, 2 m, 70 cm, and everything higher, with full power. Plus limited HF privileges:
| Band | Technician slice | Allowed modes |
|---|---|---|
| 10 m | 28.000–28.300 MHz | CW, RTTY, data |
| 10 m | 28.300–28.500 MHz | CW and SSB voice |
| 15 m | 21.025–21.200 MHz | CW only |
| 40 m | 7.025–7.125 MHz | CW only |
| 80 m | 3.525–3.600 MHz | CW only |
That 10-meter SSB slice (28.3–28.5 MHz) is the Technician's taste of worldwide voice: when solar conditions are good, 10 m opens up and a modest station talks across continents.
Power limits
The general amateur ceiling is 1500 watts PEP (peak envelope power). Technicians are limited to 200 watts PEP on HF (47 CFR §97.313(b)) — still far more than you'll ever need starting out. Most handhelds run 5 watts; most beginners never exceed 50.
The honest truth about power: on VHF/UHF, antenna height beats wattage every time. Doubling your power gains you a barely noticeable improvement; raising your antenna ten feet can double your range.
Check: Look up the ARRL band plan (search "ARRL band plan") — it shows, band by band, where voice, CW, digital, and satellite activity conventionally go. Band plans are voluntary agreements, not law, but everyone follows them, and the exam expects you to know they exist.
Next: Repeaters — how a box on a tower turns 5 watts into 50 miles.