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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.

31.6, -98.4 · EM01sn · 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
259.4
km · 161.2 mi
Bearing
45.4°
true · rev 225.4°
Terrain
BLOCKED
146.9 dB diffraction
Propagation
73/100
GOOD
Margin
-118.7
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 volume660 m AGL at the midpoint (1980 m above the chord, 990 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 20.3 m) clears with margin. The geometric line of sight is obstructed — buried 923 m below terrain at its worst point.

Great circle
31.565, -98.435 → 33.189, -96.452 · 45.4°
Loss budget · 47 GHz
FSPL (free-space) 174.2 dB
Gaseous (O₂ + H₂O) 15.6 dB
Diffraction 146.9 dB
Rain attenuation 0.0 dB
Total path loss 336.7 dB
Gas rate 0.0601 dB/km · H₂O 0.0030 dB/km/g · O₂ 0.0400 dB/km
Path abs. humidity avg 6.7 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 -336.7 dB
RX antenna gain 30.0 dBi
RX power -258.7 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -118.7 dB
Path weather · HRRR average of 9 samples
Temperature
78.7 °F
26.0 °C
Dewpoint
42.5 °F
5.8 °C
T/Td gap
36.2 °F
20.1 °C
Abs. humidity
6.7
g/m³
Pressure
964.0
mb
PWAT
13.1
mm
BL depth
2178.1
m AGL
Refrac. gradient
0
N/km
Propagation factors · 47 GHz 73/100
Rain
100 14%
Humidity
90 13%
PWAT
80 11%
Season
55 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 31.6, -98.4 22.4 °C 6.9 °C 964.0 mb 1688.8 11.7 mm
13% 31.8, -98.2 24.5 °C 6.5 °C 975.5 mb 1942.4 12.7 mm
25% 32.0, -97.9 25.4 °C 5.8 °C 978.3 mb 2042.3 12.6 mm
38% 32.2, -97.7 25.6 °C 6.0 °C 981.8 mb 2038.5 12.3 mm
Midpoint 32.4, -97.4 26.7 °C 5.4 °C 986.5 mb 2296.8 12.9 mm
63% 32.6, -97.2 25.4 °C 7.2 °C 994.8 mb 2411.9 13.1 mm
75% 32.8, -96.9 28.0 °C 5.7 °C 1000.4 mb 2390.6 14.1 mm
88% 33.0, -96.7 27.6 °C 5.0 °C 993.2 mb 2412.1 15.4 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 · 47 GHz → steady
Propagation score for this path over the next 17 hours. 0 25 50 75 100
Peak 80 at 20:00 UTC · low 64 at 11:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
20:00 80 EXCELLENT
21:00 80 EXCELLENT
22:00 72 GOOD
23:00 72 GOOD
00:00 72 GOOD
01:00 71 GOOD
02:00 69 GOOD
03:00 73 GOOD
04:00 72 GOOD
05:00 80 EXCELLENT
06:00 70 GOOD
07:00 78 GOOD
08:00 77 GOOD
09:00 76 GOOD
10:00 66 GOOD
11:00 64 MARGINAL
12:00 · now 64 MARGINAL