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NTMS Propagation Path calculator

Path Calculator

Point-to-point prediction over HRRR profiles, SRTM terrain and ITU-R P.676 / P.530.

33.5, -98.5 · EM03rm · 8.0 ft AGL

33.2, -96.5 · EM13se · 30.0 ft AGL
A callsign resolves through QRZ's mailing address, then geocoding — the position may be off from where the station actually operates.
Band
Station

Path calculation complete.

HRRR 20:00z · 9/9 path points
Distance
198.1
km · 123.1 mi
Bearing
100.7°
true · rev 280.7°
Terrain
BLOCKED
131.3 dB diffraction
Propagation
71/100
GOOD
Margin
-85.8
dB over CW threshold
Terrain profile · SRTM 30 m + canopy + MS footprints
Line of sight 1st Fresnel Duct layer Horizon ray Common volume

Over the horizon: the two horizon-skimming rays intersect at the common volume385 m AGL at the midpoint (1155 m above the chord, 578 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 24.9 m) clears with margin. The geometric line of sight is obstructed — buried 619 m below terrain at its worst point.

Great circle
33.538, -98.544 → 33.189, -96.452 · 100.7°
Loss budget · 24 GHz
FSPL (free-space) 166.0 dB
Gaseous (O₂ + H₂O) 6.6 dB
Diffraction 131.3 dB
Rain attenuation 0.0 dB
Total path loss 303.8 dB
Gas rate 0.0332 dB/km · H₂O 0.0020 dB/km/g · O₂ 0.0200 dB/km
Path abs. humidity avg 6.6 g/m³
Power budget
TX power 20.0 dBm (100.0 mW)
TX antenna gain 30.0 dBi
Feed loss (×2) -2.0 dB
EIRP 48.0 dBm
Path loss -303.8 dB
RX antenna gain 30.0 dBi
RX power -225.8 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -85.8 dB
Path weather · HRRR average of 9 samples
Temperature
80.7 °F
27.0 °C
Dewpoint
42.2 °F
5.7 °C
T/Td gap
38.4 °F
21.4 °C
Abs. humidity
6.6
g/m³
Pressure
975.5
mb
PWAT
12.9
mm
BL depth
2282.1
m AGL
Refrac. gradient
0
N/km
Propagation factors · 24 GHz 71/100
Rain
100 14%
Humidity
63 13%
PWAT
80 11%
Season
47 11%
T-Td Depression
96 10%
Refractivity
50 10%
Pressure
88 10%
Sky Cover
50 8%
Wind
50 8%
Time of Day
18 4%
Atmospheric profile HRRR 3 km Valid 2026-05-03 20:00 UTC · 9 samples
Point Lat, lon Temp Dewpt Press dN/dh BL m PWAT Duct
Source 33.5, -98.5 27.8 °C 4.5 °C 975.5 mb 2275.3 12.8 mm
13% 33.5, -98.3 27.3 °C 3.0 °C 977.1 mb 2284.3 10.7 mm
25% 33.5, -98.0 27.2 °C 4.3 °C 979.3 mb 2296.7 11.4 mm
38% 33.4, -97.8 26.8 °C 5.5 °C 985.4 mb 2284.5 12.4 mm
Midpoint 33.4, -97.5 24.9 °C 9.3 °C 985.6 mb 2215.8 14.1 mm
63% 33.3, -97.2 26.4 °C 8.5 °C 989.9 mb 2168.3 13.6 mm
75% 33.3, -97.0 27.1 °C 7.1 °C 994.6 mb 2296.0 13.4 mm
88% 33.2, -96.7 28.1 °C 4.7 °C 992.1 mb 2338.5 14.1 mm
Destination 33.2, -96.5 27.8 °C 4.1 °C 995.4 mb 2379.9 13.3 mm
Midpoint vertical profile
17-hour forecast · this path · 24 GHz → steady
Propagation score for this path over the next 17 hours. 0 25 50 75 100
Peak 72 at 20:00 UTC · low 64 at 12:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
20:00 72 GOOD
21:00 72 GOOD
22:00 72 GOOD
23:00 70 GOOD
00:00 67 GOOD
01:00 66 GOOD
02:00 69 GOOD
03:00 71 GOOD
04:00 71 GOOD
05:00 71 GOOD
06:00 71 GOOD
07:00 71 GOOD
08:00 70 GOOD
09:00 70 GOOD
10:00 71 GOOD
11:00 67 GOOD
12:00 · now 64 MARGINAL