Frequency coverage: 100KHZ-179MHZ Working voltage: 9-12V Charging interface: TYPE-C Battery: Built-in 18650 lithium battery (pay attention to the positive and negative poles of the battery when replacing the battery) Instructions: 1. Fix the stainless steel ring on the outdoor receiver. 2. The outdoor receiver and the indoor power supply are connected with a 5 or 10 meter feeder. 3. Then connect the power outlet to the radio with a 1 meter feeder. 4. When using, try to mount the antenna at a high outdoor place, the principle of electromagnetic interference 5. Charge in time when the power light is off (or the signal becomes weak) 6. Pay attention to lightning-strikes when using (disconnect the link in time) 7. Do not use the antenna to listen to the broadcast to avoid interference when charging Colour: white Material: metal + plastic Package Contents: 1 x GA490 high performance active loop antenna set Note: When using the radio to listen to the FM, please turn off the power switch for better results. SDR or malachite radios are not affected. Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.