Differences

This shows you the differences between two versions of the page.

--- bands-and-modes [2022/01/29 20:21] – m0tzo
+++ bands-and-modes [2022/01/30 16:54] (current) – m0lte
@@ Line 1: / Line 1: @@
-====== Bands and Modes ======
+==== Bands and Modes ====
 This page is meant as a modern non-exhaustive high level reference of what kinds of propagation and activity you will typically find on the common amateur radio bands. It may be UK-centric.
-^ Band ^ Daytime                          ^ Night-time                        ^ Comments                 ^ Traffic         ^
+=== Your contributions welcome! ===
-| 160m | Ground wave (120km)              | DX but antennas often compromised | Noisy with summer storms | Data modes, SSB and CW, some AM to be found. |
-| 80m  | Ground wave / NVIS               | DX                                | Lots of long-winded chat. Massively busy during contests. | Everything, lots of SSB, CW, AM and data                |
-| 60m  | Ground wave / NVIS               | DX and local                      | Channelised, shared with military, caution operating here. Full UK Licence Only | FT8, SSB. No contests. |
-| 40m  | Often open worldwide             | Often open worldwide | Bread and butter HF band. Massively busy during contests. Mind the upper limit, we have less than the US. | Everything, lots of SSB and CW and data |
-| 30m  | Open worldwide | Generally closes after sunset | Very narrow HF band | Data/CW only, no voice allowed |
-| 20m  | Open worldwide      | Closes after sunset | Bread and butter HF band. Massively busy during contests. | Everything here. A bit of a zoo. |
-| 17m  | | | "Polite 20m". No contests. | SSB, CW, FT8 |
-| 15m  | | | Big wide allocation, not much traffic | SSB, CW, FT8 |
-| 12m  | | | No contests. | SSB, CW, FT8 |
-| 10m  | Generally closed but opens when the MUF gets up this high, then comes to life! | Generally closed, but try grey-line to Japan (AM), South America (PM) | Massive wide band, great for local experimentation, FM DX | All sorts, including more FM than the HF bands. New York 10m FM repeater from the UK anyone? Perfectly possible with good conditions. |
-| 6m   | Normally no atmospheric prop | Normally no atmospheric prop | "The magic band". Sporadic E propagation makes this band look like 20m for really short periods in the spring. | FT8, SSB, FM, repeaters! |
-| 4m   | Normally no atmospheric prop | Normally no atmospheric prop| Pockets of activity around the country. Similar to 2m. | Mostly FM, but more SSB now the IC7300 exists. |
-| 2m   | Normally no atmospheric prop | Normally no atmospheric prop | Pretty much as high as sporadic E propagation ever gets. Tropospheric enhancements can open 2m up as far as southern Europe sporadically. | FM simplex, FM repeaters, APRS (including ISS), FT8, SSB, pockets of AX.25 packet. There's a TV section you can request an NoV for above 2m. Satellites at the top end of the band and CW at the bottom. |
-| 70cm | Normally no atmospheric prop | Normally no atmospheric prop | Shared with ISM / other users, some geographic restrictions on use, check your licence | FM repeaters, FM simplex, some amateur TV, lots of bleeps and bloops to decode. Satellites in this band too. |
-| 23cm (1.2GHz) | Normally no atmospheric prop | Normally no atmospheric prop | Is present on IC-9700 | SSB, repeaters, beacons, ATV |
-| 13cm (2.4GHz) | Normally no atmospheric prop | Normally no atmospheric prop| Used as the uplink band for QO-100 geostationary satellite ops. Unfortunately not open to Foundation licence holders | ATV, SSB |
-Notes:
+Please edit this page directly or make suggestions via #wiki-discussion
-  * All bands are open all the time within line of sight. This is different from "ground wave".
+^ Band                     ^ Daytime                          ^ Night-time                        ^ Comments                                                  ^ Traffic                                                                                  ^ Contests ^
+| 160m \\ 1.81-2MHz        | Ground wave (120km)              | DX but antennas often compromised | Noisy with summer storms                                  | Data modes, SSB and CW, some AM to be found.                                             | Yes      |
+| 80m  \\ 3.5-3.8MHz       | Ground wave / NVIS               | DX                                | Lots of long-winded chat. Massively busy during contests. | Everything, lots of SSB, CW, AM and data                                                 | Yes      |
+| 60m  \\ 5MHz             | Ground wave / NVIS               | DX and local                      | Channelised, shared with military, caution operating here. Full UK Licence Only | FT8, SSB. No contests.                                             | No       |
+| 40m  \\ 7.0-7.2MHz       | Often open worldwide             | Often open worldwide              | Bread and butter HF band. Massively busy during contests. Mind the upper limit, we have less than the US. | Everything, lots of SSB and CW and data  | Yes      |
+| 30m  \\ 10.1-10.15MHz    | Open worldwide                   | Generally closes after sunset     | Very narrow data-only HF band. Often great conditions.    | Data/CW only, no voice allowed                                                           | No       |
+| 20m  \\ 14.0-14.35MHz    | Open worldwide                   | Closes after sunset               | Bread and butter HF band. Massively busy during contests. | Everything here. A bit of a zoo.                                                         | Yes      |
+| 17m  \\ 18.068-18.168MHz |                                  |                                   | "Polite 20m". 20m non-contest traffic often comes here during the major contests. | SSB, CW, FT8                                                     | No       |
+| 15m  \\ 21.0-21.45MHz    |                                  |                                   | Big wide allocation, not much traffic                     | SSB, CW, FT8                                                                             | Yes      |
+| 12m  \\ 24.89-24.99MHz   |                                  |                                   | No contests.                                              | SSB, CW, FT8                                                                             | No       |
+| 10m  \\ 28.0-29.7MHz     | Generally closed but opens when the MUF gets up this high, then comes to life! | Generally closed, but try grey-line to Japan (AM), South America (PM) | Massive wide band, great for local experimentation, FM DX | All sorts, including more FM than the HF bands. New York 10m FM repeater from the UK anyone? Perfectly possible with good conditions. | Yes       |
+| 6m   \\ 50-52MHz         | Normally no atmospheric prop     | Normally no atmospheric prop      | "The magic band". Sporadic E propagation makes this band look like 20m for really short periods in the spring. | FT8, SSB, FM, repeaters!            | Yes      |
+| 4m   \\ 70-70.5MHz       | Normally no atmospheric prop     | Normally no atmospheric prop      | Pockets of activity around the country. Similar to 2m.    | Mostly FM, but more SSB now the IC7300 exists.                                           | Uncommon |
+| 2m   \\ 144-146MHz       | Normally no atmospheric prop | Normally no atmospheric prop | Pretty much as high as sporadic E propagation ever gets. Tropospheric enhancements can open 2m up as far as southern Europe sporadically. | FM simplex, FM repeaters, APRS (including ISS), FT8, SSB, pockets of AX.25 packet. There's a TV section you can request an NoV for above 2m. Satellites at the top end of the band and CW at the bottom. | Yes |
+| 70cm \\ 430-440MHz       | Normally no atmospheric prop | Normally no atmospheric prop | Shared with ISM / other users, some geographic restrictions on use, check your licence | FM repeaters, FM simplex, some amateur TV, lots of bleeps and bloops to decode. Satellites in this band too. | Uncommon |
+| 23cm \\ 1240-1325MHz     | Normally no atmospheric prop | Normally no atmospheric prop | Is present on IC-9700 | SSB, repeaters, beacons, ATV | Specialist |
+| 13cm \\ 2300-2450MHz     | Normally no atmospheric prop | Normally no atmospheric prop| Used as the uplink band for QO-100 geostationary satellite ops. Usable using transverters generally with 70cm equipment. Unfortunately not open to Foundation licence holders | ATV, SSB | Specialist |
+==== Notes ====
+  * All bands are "open" all the time within line of sight. This is different from "ground wave".
+  * A band is "open" beyond line of sight when there is atmospheric propagation. i.e. the MUF (maximum usable frequency) has drifted above the band of interest.
+  * Generally speaking, the MUF is low overnight and high during the day. Bands will "go long" or "go short" as the critical angle - the angle at which RF reflects off ionosphere layers changes.
+  * When thinking about propagation, think of the ionosphere as a thick, imperfect, curved, liquid mirror. Not as a perfect solid metal reflector.
   * CW is Continuous Wave. Morse code is the usual method of using CW.
   * Simplex is radio-to-radio
@@ Line 31: / Line 39: @@
   * Both of those sets of bands are largely accessible using homebrew equipment only
   * It can be somewhat of a surprise to newcomers that chatting around the UK can be surprisingly difficult. If this is your goal, try 160m, 80m, 40m NVIS and/or ground/wave, then VHF (6m, 4m, 2m). Use SSB and horizontal polarisation for more range up here.
+  * Rule of thumb: No FM on HF, CW at the bottom of each band, then data modes, then SSB/free-for-all. Mind the beacons.
-====== Some interesting spot frequencies ======
+==== Some interesting spot frequencies ====
-^ Band ^ Frequency ^ What/why                          ^
+^ Band ^ Frequency   ^ What/why                          ^
-| 20m  | 14.230    | SSTV. 14.233 is digital SSTV too. |
+| 2m   | 144.800     | APRS                              |
-| 20m  | 14.074    | 20m FT8                           |
+| 2m   | 145.800/825 | ISS downlink                      |
-| 30m  | 10.000    | WWV, American time station        |
+| 20m  | 14.230      | SSTV. 14.233 is digital SSTV too. |
-| 80m  |  3.76     | WAB net                           |
+| 20m  | 14.074      | 20m FT8                           |
-| 40m  |  7.16     | WAB net                           |
+| 30m  | 10.000      | WWV, American time station        |
-| ...  | ...       | ...                               |
+| 40m  | 7.16        | WAB net                           |
+| 80m  | 3.76        | WAB net                           |
+| 160m | 1.933       | 1933 net                          |
+| ...  | ...         | ...                               |