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APRS station K4SEM-9 - show graphs
Comment: 146.520MHz https://aprsdro
Location: 38°57.50' N 77°10.50' W - locator FM18JW99AX - show map
4.1 miles Northeast bearing 48° from Tysons Corner, Fairfax County, Virginia, United States [?]
6.2 miles Northeast bearing 51° from Vienna, Fairfax County, Virginia, United States
8.6 miles Northwest bearing 300° from Washington, D. C., Washington, D.C., United States
37.9 miles Southwest bearing 233° from Baltimore, City of Baltimore, Maryland, United States
Last position: 2024-12-27 16:07:21 EST (11d 21h52m ago)
2024-12-27 16:07:21 EST local time at Tysons Corner, United States [?]
Altitude: 65 ft
Position ambiguous: Precision reduced at transmitter by 2 digits, position resolution approximately 1.2 miles.
Course: 235°
Speed: 27 MPH
Device: Open Source: APRSdroid (app, Android)
Last path: K4SEM-9>APDR16 via TCPIP*,qAC,T2UKRAINE
Positions stored: 1038
Other SSIDs: K4SEM-10 K4SEM-5
Stations near current position of K4SEM-9 - show more
callsign distance last heard - EST      callsign distance last heard - EST
CW93461.0 miles 156°2025-01-08 13:45:45 GW57702.5 miles 197°2025-01-08 13:54:13
W4FMD-42.8 miles 156°2024-12-29 10:17:53 KD3M-92.9 miles 218°2024-12-19 18:14:04
KG4RHQ-73.1 miles 134°2025-01-05 11:29:19 EW38063.6 miles 311°2025-01-08 13:55:11
KO4CGD-93.9 miles 215°2024-12-29 15:10:34 DW80164.1 miles 152°2025-01-08 13:54:23
NV4FM-54.2 miles 211°2025-01-08 13:38:43 NV4FM A4.3 miles 211°2025-01-06 01:23:19
NV4FM AD4.3 miles 211°2025-01-06 01:23:19 NV4FM B4.3 miles 211°2025-01-06 01:23:19
NV4FM C4.3 miles 211°2025-01-06 01:23:19 NV4FM-A4.3 miles 211°2025-01-06 01:43:32
NV4FM-C4.3 miles 211°2025-01-06 01:43:32 NV4FM-B4.3 miles 211°2025-01-06 01:43:32
DW62794.4 miles 83°2025-01-08 13:55:37 KC3BBT-134.4 miles 83°2025-01-08 13:45:35
NN4DL-134.7 miles 214°2025-01-04 07:21:50 KC3BBT-94.7 miles 82°2025-01-07 18:21:45
About this site
This page shows real-time information collected from the Automatic Position Reporting System Internet network (APRS-IS). APRS is used by amateur (ham) radio operators to transmit real-time position information, weather data, telemetry and messages over the radio. A vehicle equipped with a GPS receiver, a VHF transmitter or HF transceiver and a small computer device called a tracker transmits it's location, speed and course in a small data packet, which is then received by a nearby iGate receiving site which forwards the packet on the Internet. Systems connected to the Internet can send information on the APRS-IS without a radio transmitter, or collect and display information transmitted anywhere in the world.
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