The Predicted Coverage of the
NLARC 448.650/443.650 FM Repeater

The propagation prediction plot above was generated using the excellent Radio Mobile Freeware V 3.7.8 application by VE2DBE for radio propagation and virtual mapping. Additionally, you may visit the Virginia Digitial Emergency Network (VDEN) site to obtain various maps.

The plot above was generated using the following parameters:

• Antenna height above ground level (230 feet/70 meters).
• Transmitter Power (40 Watts at transmitter).
• Duplexer insertion loss(-1.4 dB).
• 50' of 7/8" Andrew LDF5-50A Coaxial cable loss (-0.4 dB).
• 10' of RG-213 coaxial cable loss (-0.5 dB).
• A cartoid pattern antenna gain of 8 phased array dipoles oriented toward 230 degress magnetic (+9 dB).

The resulting gain of the filter/feeder/antenna section is [(-1.4) + (-0.4) + (-0.5) + (+9.0)] = +6.7 dB. Factored into the 40 Watts output directly from the transmitter, this results in an 187 Watt ERP (effective rated power) rating.

Web page operations: James E. Byrd
Responsible NASA Official: Richard S. Eckman