Chengdu Ebyte Electronic Technology Co,;Ltd E30 -490T20S user manual
Copyright ©2012–2019
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Chengdu Ebyte Electronic Technology Co,;Ltd
16
the module needs to be reliably grounded.
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Please pay attention to the correct connection of the positive and negative poles of the power supply. Reverse
connection may cause permanent damage to the module
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Please check the power supply to ensure it is within the recommended voltage otherwise when it exceeds the
maximu m value the module will be permanently damaged
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Please check the stability of the power supply, the voltage can not be fluctuated frequently
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When designing the power supply circuit for the module, it is often recommended to reserve more than 30% of the
margin, so the whole machine is beneficial for long-term stable operation.
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The module should be as far away as possible from the power supply, transformers, high -frequency wiring and other
parts with large electromagnetic interference.
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High-frequency digital routing, high-frequency analog routing, and power routing must be avoided under the module.
If it is necessary to pass through the module, assume that the module is soldered t o the Top Layer, and the copper is
spread on the Top Layer of the module contact part(well grounded), it must be close to the digital part of the module
and routed in the Bottom Layer
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Assuming the module is soldered or placed over the Top Layer, it is wro ng to randomly route over the Bottom Layer
or other layers, which will affect the module's spurs and receiving sensitivity to varying degrees
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It is assumed that there are devices with large electromagnetic interference around the module that will greatly affect
the performance. It is recommended to keep them away from the module according to the 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)
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Try to stay away from some physical layers such as TTL protocol at 2.4GHz , fo r example: USB3.0
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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.
9 FAQ
9.1 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 groun d.
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
distance).
