What is a Doppler? What is a Roanoke Doppler?
Nineteenth Century physicist Christian Doppler is credited with creating equations that describe the apparent frequency shifts that result from the relative motion of the sender and receiver of a wave. The Doppler principle is now used for many applications, including dating the universe and catching highway speeders. In radio direction finding, a simulated rotating antenna can be used to determine the direction of an incoming signal using this principle. When transmitter hunters speak of Dopplers, they usually mean a device with an electronically rotating array of 3 to 8 vertically oriented whips or dipoles and a circular display of 8 to 50 light-emitting diodes. These Doppler add-ons work with VHF and UHF narrowband FM receivers. There are other RDF devices with similar antenna sets and displays that are used with AM receivers (e.g Watson-Watt), but these are not Doppler sets. The Roanoke Doppler was first published in my book “TRANSMITTER HUNTING—Radio Direction Finding Simplified
Nineteenth Century physicist Christian Doppler is credited with creating equations that describe the apparent frequency shifts that result from the relative motion of the sender and receiver of a wave. The Doppler principle is now used for many applications, including dating the universe and catching highway speeders. In radio direction finding, a simulated rotating antenna can be used to determine the direction of an incoming signal using this principle. When transmitter hunters speak of Dopplers, they usually mean a device with an electronically rotating array of 3 to 8 vertically oriented whips or dipoles and a circular display of 8 to 50 light-emitting diodes. These Doppler add-ons work with VHF and UHF narrowband FM receivers. There are other RDF devices with similar antenna sets and displays that are used with AM receivers (e.g Watson-Watt), but these are not Doppler sets. The Roanoke Doppler was first published in my book “TRANSMITTER HUNTING—Radio Direction Finding Simplified
