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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.

35.2, -93.6 · EM35ee · 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
356.2
km · 221.3 mi
Bearing
230.9°
true · rev 50.9°
Terrain
BLOCKED
137.3 dB diffraction
Propagation
69/100
GOOD
Margin
-85.3
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 volume1245 m AGL at the midpoint (3734 m above the chord, 1867 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 51.7 m) clears with margin. The geometric line of sight is obstructed — buried 1571 m below terrain at its worst point.

Great circle
35.175, -93.646 → 33.12, -96.615 · 230.9°
Loss budget · 10 GHz
FSPL (free-space) 163.5 dB
Gaseous (O₂ + H₂O) 2.5 dB
Diffraction 137.3 dB
Rain attenuation 0.0 dB
Total path loss 303.3 dB
Gas rate 0.0070 dB/km · H₂O 0.0000 dB/km/g · O₂ 0.0070 dB/km
Path abs. humidity avg 7.8 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 -303.3 dB
RX antenna gain 30.0 dBi
RX power -225.3 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -85.3 dB
Path weather · HRRR average of 9 samples
Temperature
80.2 °F
26.8 °C
Dewpoint
46.4 °F
8.0 °C
T/Td gap
33.8 °F
18.8 °C
Abs. humidity
7.8
g/m³
Pressure
976.1
mb
PWAT
15.6
mm
BL depth
2147.5
m AGL
Refrac. gradient
0
N/km
Propagation factors · 10 GHz 69/100
Rain
100 14%
Humidity
82 13%
PWAT
75 11%
Season
68 11%
T-Td Depression
55 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 35.2, -93.6 26.6 °C 9.4 °C 999.2 mb 2119.4 16.9 mm
13% 34.9, -94.0 24.8 °C 10.0 °C 980.7 mb 1872.5 15.7 mm
25% 34.7, -94.4 24.1 °C 11.4 °C 976.1 mb 1426.3 15.1 mm
38% 34.4, -94.8 24.8 °C 11.2 °C 985.5 mb 1760.2 14.7 mm
Midpoint 34.1, -95.1 27.7 °C 8.0 °C 997.6 mb 2338.8 15.1 mm
63% 33.9, -95.5 29.0 °C 7.2 °C 1000.0 mb 2608.1 17.9 mm
75% 33.6, -95.9 27.4 °C 6.2 °C 994.4 mb 2332.2 14.9 mm
88% 33.4, -96.2 28.4 °C 4.9 °C 991.2 mb 2492.0 16.1 mm
Destination 33.1, -96.6 28.2 °C 3.9 °C 994.1 mb 2377.9 13.9 mm
Midpoint vertical profile
17-hour forecast · this path · 10 GHz → steady
Propagation score for this path over the next 17 hours. 0 25 50 75 100
Peak 82 at 11:00 UTC · low 69 at 03:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
20:00 75 GOOD
21:00 75 GOOD
22:00 75 GOOD
23:00 74 GOOD
00:00 75 GOOD
01:00 75 GOOD
02:00 75 GOOD
03:00 69 GOOD
04:00 71 GOOD
05:00 71 GOOD
06:00 71 GOOD
07:00 70 GOOD
08:00 72 GOOD
09:00 80 EXCELLENT
10:00 81 EXCELLENT
11:00 82 EXCELLENT
12:00 · now 81 EXCELLENT