What signals will the DF work with – AM, FM, TV, SSB, Noise, CW, Pulse?

When the unit is used as recommended with a narrow band FM receiver, it will work with any signal that has a carrier that remains within the IF bandwidth of the receiver. This would include unmodulated carriers, narrow band fm modulated signals, and amplitude modulated signals. It will also work with most digitally encoded signals (e.g. P25); however, in some cases it may be necessary to use a sweep rate of 500 or 2000 Hz. Television video carriers can also be used, but the system will not track broadband noise or single sideband signals.

Commercial broadcast (wideband) FM signals require that the receiver bandwidth be increased to 150 KHz. Our direction finders provides a selectable sweep rate, and by setting it to the highest level, the deviation is increased to the point where a wide band FM signal may be tracked. Accuracy and sensitivity, however, will be lower.  Using a larger number of averages is also helpful; however, you will need to make longer stationary readings in the mobile application.

The latest firmware version provided with all of our direction finding systems allows signals as short as 80 milliseconds to be tracked. Longer duration signals provide more stable and accurate bearings and we recommend using the system with pulsed transmitters of 100 milliseconds or longer.