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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.

33.7, -99.1 · EM03kq · 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
255.7
km · 158.9 mi
Bearing
102.2°
true · rev 282.2°
Terrain
BLOCKED
128.4 dB diffraction
Propagation
68/100
GOOD
Margin
-72.8
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 volume642 m AGL at the midpoint (1925 m above the chord, 962 m above the 4/3 horizon), so its Fresnel zone (F₁ ≈ 43.8 m) clears with margin. The geometric line of sight is obstructed — buried 967 m below terrain at its worst point.

Great circle
33.702, -99.139 → 33.189, -96.452 · 102.2°
Loss budget · 10 GHz
FSPL (free-space) 160.6 dB
Gaseous (O₂ + H₂O) 1.8 dB
Diffraction 128.4 dB
Rain attenuation 0.0 dB
Total path loss 290.8 dB
Gas rate 0.0070 dB/km · H₂O 0.0000 dB/km/g · O₂ 0.0070 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 -290.8 dB
RX antenna gain 30.0 dBi
RX power -212.8 dBm
Sensitivity (CW, 500 Hz) -141.0 dBm
Margin -72.8 dB
Path weather · HRRR average of 9 samples
Temperature
80.7 °F
27.1 °C
Dewpoint
42.0 °F
5.6 °C
T/Td gap
38.7 °F
21.5 °C
Abs. humidity
6.6
g/m³
Pressure
975.6
mb
PWAT
12.9
mm
BL depth
2297.8
m AGL
Refrac. gradient
0
N/km
Propagation factors · 10 GHz 68/100
Rain
100 14%
Humidity
70 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 33.7, -99.1 27.7 °C 4.3 °C 975.6 mb 2368.5 12.4 mm
13% 33.6, -98.8 27.3 °C 5.2 °C 977.2 mb 2293.4 12.7 mm
25% 33.6, -98.5 27.4 °C 4.7 °C 979.4 mb 2289.4 12.2 mm
38% 33.5, -98.1 26.9 °C 4.2 °C 977.4 mb 2296.8 11.4 mm
Midpoint 33.4, -97.8 26.3 °C 5.4 °C 979.5 mb 2258.2 11.7 mm
63% 33.4, -97.5 24.9 °C 9.3 °C 985.6 mb 2215.8 14.1 mm
75% 33.3, -97.1 27.3 °C 8.1 °C 993.0 mb 2239.7 13.9 mm
88% 33.3, -96.8 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 · 10 GHz → steady
Propagation score for this path over the next 17 hours. 0 25 50 75 100
Peak 83 at 05:00 UTC · low 72 at 01:00 UTC
Hour-by-hour propagation score for this path — the series plotted above.
Hour UTC Score Rating
20:00 74 GOOD
21:00 74 GOOD
22:00 74 GOOD
23:00 74 GOOD
00:00 77 GOOD
01:00 72 GOOD
02:00 80 EXCELLENT
03:00 76 GOOD
04:00 79 GOOD
05:00 83 EXCELLENT
06:00 83 EXCELLENT
07:00 82 EXCELLENT
08:00 80 EXCELLENT
09:00 81 EXCELLENT
10:00 81 EXCELLENT
11:00 72 GOOD
12:00 · now 74 GOOD