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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.

33.8, -97.9 · EM13at · 8.0 ft AGL

33.1, -96.6 · EM13qc · 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
143.9
km · 89.4 mi
Bearing
121.2°
true · rev 301.2°
Terrain
BLOCKED
120.9 dB diffraction
Propagation
70/100
GOOD
Margin
-71.1
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 volume203 m AGL at the midpoint (610 m above the chord, 305 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 21.2 m) clears with margin. The geometric line of sight is obstructed — buried 343 m below terrain at its worst point.

Great circle
33.798, -97.937 → 33.12, -96.615 · 121.2°
Loss budget · 24 GHz
FSPL (free-space) 163.2 dB
Gaseous (O₂ + H₂O) 5.0 dB
Diffraction 120.9 dB
Rain attenuation 0.0 dB
Total path loss 289.1 dB
Gas rate 0.0344 dB/km · H₂O 0.0020 dB/km/g · O₂ 0.0200 dB/km
Path abs. humidity avg 7.2 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 -289.1 dB
RX antenna gain 30.0 dBi
RX power -211.1 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -71.1 dB
Path weather · HRRR average of 9 samples
Temperature
80.4 °F
26.9 °C
Dewpoint
44.5 °F
6.9 °C
T/Td gap
35.9 °F
19.9 °C
Abs. humidity
7.2
g/m³
Pressure
974.0
mb
PWAT
14.6
mm
BL depth
2262.3
m AGL
Refrac. gradient
0
N/km
Propagation factors · 24 GHz 70/100
Rain
100 14%
Humidity
56 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 33.8, -97.9 27.1 °C 6.3 °C 984.2 mb 2305.5 13.7 mm
13% 33.7, -97.8 27.4 °C 6.1 °C 983.1 mb 2318.3 14.0 mm
25% 33.6, -97.6 24.8 °C 8.8 °C 974.0 mb 2197.3 14.3 mm
38% 33.5, -97.4 25.4 °C 7.3 °C 982.6 mb 2056.9 12.5 mm
Midpoint 33.5, -97.3 26.4 °C 8.3 °C 986.2 mb 2113.6 14.2 mm
63% 33.4, -97.1 27.3 °C 7.0 °C 993.0 mb 2235.5 14.1 mm
75% 33.3, -96.9 27.0 °C 6.4 °C 994.5 mb 2280.0 15.1 mm
88% 33.2, -96.8 28.1 °C 5.7 °C 991.9 mb 2354.5 15.8 mm
Destination 33.1, -96.6 28.4 °C 6.3 °C 993.9 mb 2499.5 17.5 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 75 at 03:00 UTC · low 65 at 12:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
20:00 71 GOOD
21:00 73 GOOD
22:00 74 GOOD
23:00 73 GOOD
00:00 71 GOOD
01:00 71 GOOD
02:00 71 GOOD
03:00 75 GOOD
04:00 72 GOOD
05:00 72 GOOD
06:00 72 GOOD
07:00 73 GOOD
08:00 72 GOOD
09:00 71 GOOD
10:00 72 GOOD
11:00 68 GOOD
12:00 · now 65 GOOD