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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, -97.9 · EM13bn · 8.0 ft AGL

33.1, -96.6 · EM13qc · 60.0 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 08:00z · 9/9 path points
Distance
124.1
km · 77.1 mi
Bearing
112.1°
true · rev 292.1°
Terrain
BLOCKED
110.9 dB diffraction
Propagation
63/100
MARGINAL
Margin
-60.7
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 volume151 m AGL at the midpoint (453 m above the chord, 227 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 19.7 m) clears with margin. The geometric line of sight is obstructed — buried 218 m below terrain at its worst point.

Great circle
33.546, -97.85 → 33.12, -96.615 · 112.1°
Loss budget · 24 GHz
FSPL (free-space) 161.9 dB
Gaseous (O₂ + H₂O) 5.9 dB
Diffraction 110.9 dB
Rain attenuation 0.0 dB
Total path loss 278.7 dB
Gas rate 0.0472 dB/km · H₂O 0.0020 dB/km/g · O₂ 0.0200 dB/km
Path abs. humidity avg 13.6 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 -278.7 dB
RX antenna gain 30.0 dBi
RX power -200.7 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -60.7 dB
Path weather · HRRR average of 9 samples
Temperature
73.2 °F
22.9 °C
Dewpoint
61.4 °F
16.3 °C
T/Td gap
11.8 °F
6.6 °C
Abs. humidity
13.6
g/m³
Pressure
972.1
mb
PWAT
25.9
mm
BL depth
308.4
m AGL
Refrac. gradient
-105.1
N/km · super-refractive
Propagation factors · 24 GHz 63/100
Rain
100 14%
Humidity
2 13%
PWAT
60 11%
Season
47 11%
T-Td Depression
60 10%
Refractivity
72 10%
Pressure
88 10%
Sky Cover
50 8%
Wind
50 8%
Time of Day
55 4%
Atmospheric profile HRRR 3 km Valid 2026-05-15 08:00 UTC · 9 samples
Point Lat, lon Temp Dewpt Press dN/dh BL m PWAT Duct
Source 33.5, -97.9 22.7 °C 17.0 °C 972.9 mb -97.8 329.3 30.7 mm
13% 33.5, -97.7 22.0 °C 17.5 °C 972.1 mb -105.1 323.8 29.9 mm
25% 33.4, -97.5 21.9 °C 17.1 °C 975.1 mb -87.1 309.1 28.2 mm
38% 33.4, -97.4 21.8 °C 17.7 °C 976.0 mb -97.7 279.9 27.2 mm
Midpoint 33.3, -97.2 22.1 °C 17.1 °C 982.5 mb -90.2 320.8 26.4 mm
63% 33.3, -97.1 23.7 °C 14.8 °C 985.8 mb -70.2 338.3 24.0 mm
75% 33.2, -96.9 24.1 °C 14.8 °C 988.5 mb -59.0 323.9 23.2 mm
88% 33.2, -96.8 23.6 °C 14.9 °C 985.3 mb -68.1 283.7 22.0 mm
Destination 33.1, -96.6 24.1 °C 16.0 °C 987.4 mb -91.5 266.6 22.0 mm
Midpoint vertical profile
18-hour forecast · this path · 24 GHz → steady
Propagation score for this path over the next 18 hours. 0 25 50 75 100
Peak 64 at 19:00 UTC · low 52 at 22:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
08:00 60 MARGINAL
09:00 61 MARGINAL
10:00 61 MARGINAL
11:00 58 MARGINAL
12:00 60 MARGINAL
13:00 59 MARGINAL
14:00 59 MARGINAL
15:00 60 MARGINAL
16:00 57 MARGINAL
17:00 61 MARGINAL
18:00 61 MARGINAL
19:00 64 MARGINAL
20:00 62 MARGINAL
21:00 57 MARGINAL
22:00 52 MARGINAL
23:00 54 MARGINAL
00:00 54 MARGINAL
01:00 · now 53 MARGINAL