Nagano Japan Radio Co . Ltd. NJT511 ユーザーズマニュアル

 

 

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The BHT-300BW supports spread spectrum communication. 

•  If there are too many communications errors, first make sure that the BHT points 

directly at an access point because the 2.4-GHz band requires a more or less 
straight line path. Note also that the low-power radio waves have trouble passing 
through human bodies and other obstacles along that path. 

•  This link will not operate properly in the vicinity of microwave ovens, industrial 

heaters, high-frequency medical equipment, and other sources of radio waves in 
the 2.4-GHz band. 

• Electromagnetic noise from personal computers, refrigerators, and other home 

appliances can also interfere with link operation. 

• Environmental factors that can also interfere with link operation include large 

metallic objects, metallic dust, or metallic walls in the vicinity of the path and 
vibration at either end. 

 

 

To System Designers: 

• Before developing the application, make sure that the intended

environment is free of the interference factors above and thus actually
capable of supporting link operation. 

•  Assume that there will be communications failures requiring robust retry

capabilities in the software. 

• When introducing the BHT link operation into an environment where

equipment using radio waves in the 2.4-GHz band operates or when
introducing such equipment after the introduction of the BHT link
operation, be sure to confirm that the BHT radio link operates properly
with all equipment being in operation beforehand. 

•  If the environment of the radio communications system is changed after

the introduction (e.g., newly installed household appliances and
movement/addition of shelves or objects), then confirm that the radio link 
operates properly again before the actual use.