Users Manual

Chengdu Ebyte Electronic Technology Co., Ltd. E22-900T30S User manual
Copyright ©2012–2018，Chengdu Ebyte Electronic Technology Co.,Ltd.
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strength of the interference. If necessary, appropriate isolation and shielding can be done；
 Assume that there are traces with large electromagnetic interference (high-frequency digital,
high-frequency analog, power traces) around the module that will greatly affect the performance of the
module. It is recommended to stay away from the module according to the strength of the interference.If
necessary, appropriate isolation and shielding can be done.
 If the communication line uses a 5V level, a 1k-5.1k resistor must be connected in series (not
recommended, there is still a risk of damage)；
 Try to stay away from some physical layers such as TTL protocol at 2.4GHz , for example: USB3.0；
 The mounting structure of antenna has a great influence on the performance of the module. It is necessary
to ensure that the antenna is exposed, preferably vertically upward. When the module is mounted inside
the case, use a good antenna extension cable to extend the antenna to the outside；
 The antenna must not be installed inside the metal case, which will cause the transmission distance to be
greatly weakened.
11 FAQ
11.1 Communication range is too short
 The communication distance will be affected when obstacle exists.
 Data lose rate will be affected by temperature, humidity and co-channel interference.
 The ground will absorb and reflect wireless radio wave, so the performance will be poor when testing near ground.
 Sea water has great ability in absorbing wireless radio wave, so performance will be poor when testing near the sea.
 The signal will be affected when the antenna is near metal object or put in a metal case.
 Power register was set incorrectly, air data rate is set as too high (the higher the air data rate, the shorter the