N4DBM is a receive only APRS station which takes over the air data from 144.390 MHz (mobile, weather and home stations) and inputs this data into the APRS network and also posts "best DX" which is the farthest received station heard by N4DBM every five minutes. This aids in looking to see whether there is a band opening in a certain direction. You may see "best DX" by clicking on "raw data" link above. Many VHF and UHF operators are using APRS to determine if a propagation is in favor. See Jon Harder NG0E's description of how his site takes data from the APRS servers and uses it to visually show propagation status.

N4DBM receives off an antenna located near Bladenboro NC, which is 12 miles south-east of Lumberton, or 50 miles north of Myrtle Beach. The property where the tower is located actually belongs to KG4PTU. The antenna is a Celwave PD-340 mounted at 115 feet above ground level. The receiver is a Yaesu FT-2400. The received data is fed into a Clegg FM-76 and re-transmits this audio on a 220 MHz simplex frequency to the home location of N4DBM (approximately 2.5 miles north-west of the tower site) where there is an internet connection. There it is received by another Clegg FM-76 and fed into a PacComm TNC-320. We are using an old Gateway Pentium PC (also shared with the N4DBM-2 weather station) and connected via Road Runner 768 K internet connection.

N4DBM does NOT transmit over the air. There is already enough APRS activity on 144.390 and a nearby digipeater (W4LBT-9) located on a broadcast tower about 25 miles north-west of us. It does a good job in this area of re-transmitting mobiles and other APRS stations. Adding more transmitters to 144.390 does nothing but clog up the frequency, preventing stations that actually need to be heard (like mobiles) from getting their data into the network.

The I-Gate PC and internet connection, as well as the receiver and link radios are powered by battery backup devices which should provide emergency power for at least 24 hours.