Hubsan X4 501S is a cost-effective small drone quadcopter, but image transmission distance just about 300 meters, if you want extend the transmission distance, it's easy, even no necessary change the antenna, just follow these 3 steps:
1. As shown below image, original antenna head is inward direction, put this antenna to get down, let it outward, and as far as possible by remote control edge
2. Like following image, 5.8g receiver original is mounted to the inside, to make it as close to the front, near the remote edges, and pouring sealant.
3. As shown below: separated in the middle with aluminum foil, then gumming, remember higher a little, the back cover just to suppress.
Thus, modification is completed, should be noted that, 2.4G inclined 45 degrees to install, 5.8g flat antenna, please try to tilt outward or parallel with the housing, this can be slightly adjusted by the test.
Upon completion, re-frequency remote control and aircraft:
Press the camera button, open the remote control, below appears plan xxxxxx fonts, aircraft close to remote control, power on, after a few seconds, frequency success.
How to test?
Power on the H501S, into an enclosed space, and then take remote control away from the aircraft, until the image starts to flash (close no image), then enter the remote control menu (menu can appears), compare the screen effect is there a difference with the previous effect, if there is, prove interference persists, 5.8G and 2.4G antenna to fine-tune, if there is no difference in effect or difference is very small, congratulations to you, eliminate interference successful.
This is because the 2.4G transmission will interfere received on 5.8G, so simply following the above three steps, we can achieve the effect of anti-interference, then the distance can reach 1200m.
Look this test video after modificate.