Playing Radio

Solar Conditions & Ham Radio Propagation

Understanding propagation conditions

  • Radio Blackouts
    • X-Ray – X20 Extreme, X10 Severe, X1 Strong, M5 Moderate, M1 Minor, C1 Active, A1-B9 No/Small Flare (Note: Affect on sunlit side of HF)
    • Ptn Flx (Proton Flux) – 1,000,000 Extreme, 100,000 Severe, 10,000 Strong, 1,000 Moderate, 100 Minor, 10 Active, 1 Normal (Note: Affect on polar regions)
  • Geomagnetic Storms
    • K9 = S30+ Impossible, K8 = S20-S30 Sporadic, K7 = S9-S20 Intermittent, K6 = S6-S9 HF fade higher latitudes 55′, K5 = S4-S6 HF fader higher latitudes 56′, K3-4 = S2-S3 Minor HF Fade, K0-2 No impact
  • Band Openings
    • SN (Solar Flux)
      • SN=160-250 Reliable communications all bands up through 6m
      • SN=105-160 Excellent conditions all bands up through 10m (w/6m openings)
      • SN=70-105 Fair to good conditions all bands up through 10m
      • SN=35-70 Fair conditions all bands up through 15m
      • SN=10-35 Poor to fair conditions all bands up through 20m
      • SN=0-10 Bands above 40m unusable

Typical Use Times

  • 10M – Morning and early evening (28.300 – 28.500 SSB Tech)
  • 20M – Day
  • 40M – Night
  • 80M – Night with low solar activity

Beacons – https://www.ncdxf.org/ (14.100, 18.110, 21.150, 24.930, 28.200 MHz)

FT8 Frequencies – https://www.dxzone.com/ft8-frequencies/

Bands

160 Meters (1.8-2.0 MHz)
1.800 - 2.000CW
1.800 - 1.810Digital Modes
1.810CW QRP
1.843-2.000SSB, SSTV and other wideband modes
1.910SSB QRP
1.995 - 2.000Experimental
1.999 - 2.000Beacons
80 meters (3.5-3.8 MHz) [LSB]
3.590RTTY/Data DX
3.570-3.600RTTY/Data
3.790-3.800DX window
3.845SSTV
3.885AM calling frequency
60 Meters (5 MHz channels)
5330.5USB phone and CW/RTTY/data *
5346.5USB phone and CW/RTTY/data *
5357.0USB phone and CW/RTTY/data *
5371.5USB phone and CW/RTTY/data *
5403.5USB phone and CW/RTTY/data *
  • Only one signal at a time is permitted on any channel, Maximum effective radiated output is 100 W PEP
  • USB is limited to 2.8 kHz, CW and digital emissions must be centered 1.5 kHz above the channel frequencies indicated in the above chart
40 meters (7.0-7.1 MHz) [LSB]
7.040RTTY/Data DX
7.080-7.125RTTY/Data
7.171SSTV
7.290AM calling frequency
30 Meters (10.1-10.15 MHz) [USB]
10.130-10.140RTTY
10.140-10.150Packet
20 meters (14.0-14.35 MHz) [USB]
14.070-14.095RTTY
14.095-14.0995Packet
14.100NCDXF Beacons
14.1005-14.112Packet
14.230SSTV
14.286AM calling frequency
17 Meters (18.068-18.168 MHz) [USB]
18.100-18.105RTTY
18.105-18.110Packet
15 meters (21.0-21.45 MHz) [USB]
21.070-21.110RTTY/Data
21.340SSTV
12 Meters (24.89-24.99 MHz) [USB]
24.920-24.925RTTY
24.925-24.930Packet
10 meters (28.0-29.7 MHz) [USB]
28.000-28.070CW
28.070-28.150RTTY
28.150-28.190CW
28.200-28.300Beacons
28.300-29.300Phone
28.680SSTV
29.000-29.200AM
29.300-29.510Satellite Uplinks or Downlinks
29.520-29.590Repeater Inputs
29.600FM Simplex
29.610-29.700Repeater Outputs
6 meters (50-54 MHz) [USB]
50.0-50.1CW, beacons
50.060-50.080Beacon subband
50.1-50.3SSB, CW
50.10-50.125DX window
50.125SSB calling
50.3-50.6All modes
50.6-50.8Nonvoice communications
50.62Digital (packet) calling
50.8-51.0Radio remote control (20-kHz channels)
51.0-51.1Pacific DX window
51.12-51.48Repeater inputs (19 channels)
51.12-51.18Digital repeater inputs
51.5-51.6Simplex (six channels)
51.62-51.98Repeater outputs (19 channels)
51.62-51.68Digital repeater outputs
52.0-52.48Repeater inputs (except as noted; 23 channels)
52.02, 52.04FM simplex
52.2TEST PAIR (input)
52.5-52.98Repeater output (except as noted; 23 channels)
52.525Primary FM simplex
52.54Secondary FM simplex
52.7TEST PAIR (output)
53.0-53.48Repeater inputs (except as noted; 19 channels)
53.0Remote base FM simplex
53.02Simplex
53.1, 53.2, 53.3, 53.4Radio remote control
53.5-53.98Repeater outputs (except as noted; 19 channels)
53.5, 53.6, 53.7, 53.8Radio remote control
53.52, 53.9Simplex
2 Meters (144-148 MHz) [USB]
144.00-144.05EME (CW)
144.05-144.10General CW and weak signals
144.10-144.20EME and weak-signal SSB
144.200National calling frequency
144.200-144.275General SSB operation
144.275-144.300Propagation beacons
144.30-144.50New OSCAR subband
144.50-144.60Linear translator inputs
144.60-144.90FM repeater inputs
144.90-145.10Weak signal and FM simplex (145.01,03,05,07,09 are widely used for packet)
145.10-145.20Linear translator outputs
145.20-145.50FM repeater outputs
145.50-145.80Miscellaneous and experimental modes
145.80-146.00OSCAR subband
146.01-146.37Repeater inputs
146.40-146.58Simplex
146.52National Simplex Calling Frequency
146.61-146.97Repeater outputs
147.00-147.39Repeater outputs
147.42-147.57Simplex
147.60-147.99Repeater inputs
1.25 Meters (222-225 MHz) [USB]
222.0-222.150Weak-signal modes
222.0-222.025EME
222.05-222.06Propagation beacons
222.1SSB & CW calling frequency
222.10-222.15Weak-signal CW & SSB
222.15-222.25Local coordinator's option; weak signal, ACSB, repeater inputs, control
222.25-223.38FM repeater inputs only
223.40-223.52FM simplex
223.52-223.64Digital, packet
223.64-223.70Links, control
223.71-223.85Local coordinator's option; FM simplex, packet, repeater outputs
223.85-224.98Repeater outputs only
70 centimeters (430-440 MHz) [USB]
420.00-426.00ATV repeater or simplex with 421.25 MHz video carrier control links and experimental
426.00-432.00ATV simplex with 427.250-MHz video carrier frequency
432.00-432.07EME (Earth-Moon-Earth)
432.07-432.10Weak-signal CW
432.1070-cm calling frequency
432.10-432.30Mixed-mode and weak-signal work
432.30-432.40Propagation beacons
432.40-433.00Mixed-mode and weak-signal work
433.00-435.00Auxiliary/repeater links
435.00-438.00Satellite only (internationally)
438.00-444.00ATV repeater input with 439.250-MHz video carrier frequency and repeater links
442.00-445.00Repeater inputs and outputs (local option)
445.00-447.00Shared by auxiliary and control links, repeaters and simplex (local option)
446.00National simplex frequency
447.00-450.00Repeater inputs and outputs (local option)

The convention of using Lower Sideband (LSB) below 10 MHz and Upper Sideband (USB) above 10 MHz is generally followed in amateur radio operations.

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