Why are there only 16 LEDs on the Roanoke Doppler?
The Roanoke Doppler was designed for the best combination of simplicity and performance. A 16 LED display is usually quite adequate for tracking signals when mobile in urban areas. It gives a rapid indication of which way to drive when time is of essence. I still use my 16-LED unit on the local hunts with good results. When I need higher accuracy for triangulation, I switch to a beam. Finer resolution is possible with some circuit changes. Tom Curlee WB6UZZ has designed a version with digital readout to the nearest degree. But the basic bearing accuracy of VHF Dopplers on vehicles is typically +/- 5 degrees, so such a display gives a false sense of accuracy. And all these improvements require more complexity. That means more parts to find and greater cost. We have found that most hams want maximum simplicity in projects they have to build themselves. (On the other hand, when they buy a ready-to-use piece of gear, they want maximum bells and whistles.
The Roanoke Doppler was designed for the best combination of simplicity and performance. A 16 LED display is usually quite adequate for tracking signals when mobile in urban areas. It gives a rapid indication of which way to drive when time is of essence. I still use my 16-LED unit on the local hunts with good results. When I need higher accuracy for triangulation, I switch to a beam. Finer resolution is possible with some circuit changes. Tom Curlee WB6UZZ has designed a version with digital readout to the nearest degree. But the basic bearing accuracy of VHF Dopplers on vehicles is typically +/- 5 degrees, so such a display gives a false sense of accuracy. And all these improvements require more complexity. That means more parts to find and greater cost. We have found that most hams want maximum simplicity in projects they have to build themselves.
