All such products currently need to have an external antenna.

目前所有产品都需要一根外置天线。

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The short range of the induction-loop antenna in the lens means the external antenna has to be very close to the eye: taped around the eye socket, in fact.

眼镜内感应圈天线短意味着外部天线离眼睛一定很近：实际上就是黏在眼眶周围。

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“The external antenna on iPhone 4 is located in the stainless steel band,” reads the caption under a photo indicating where the problem exists on Apple’s page (image to the right).

“iPhone 4的外置天线设计在外壳的不锈钢圈上，”一张出现在苹果主页上显示这个问题的图片（右图）下方的说明文字。

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This is because these systems are designed with the understanding that an external antenna is needed.

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