Portable wideband VLF antenna for listening to natural radio emissions Tweeks and Whistlers and low frequency radio in the range up to 80 Khz. For reception of the ULF and VLF band and LF bands and for listening to Tweeks and Whistlers and other natural radio waves. Self Resonant at 80 KHz. Simply connect this antenna directly to the microphone input of a sensitive tape recorder, digital audio recorder, or audio amplifier and listen to it away from powerlines and other sources of man-made noise at night to hear the beautiful sounding Tweeks and the more rare Whistlers. 25 inches long X 2.5 inches wide.