使用長天線收音機考試問題...

Just from the physics perspective, antenna in radio is only for receiving signals. A radio would not transmit any radiowaves through its antenna. There should not be any interference with other radios nearby.

The prohibition of using a "long anetnna" in a crowded public examination hall is just to avoid causing physical disturbance to other candidates siting at the vicinity.

2010-03-19 20:04:30 補充：
Q:你最後指的"physical disturbance"係阻礙視線的意思?
This refers to any nuisance caused by the long antenna, as it may easily hit other candidates sitting next to you.

2010-03-19 20:11:47 補充：
Q:點解咁多人都會覺得長天線收音機會干擾其他收音機?
From the web discussion that you refer to, there is no confirmation that the use of a long antenna will cause (radio) disturbance to others. In fact, the quality of radio reception depends very much on the location inside a room and the direction of the internal antenna.

只係長天線唔會干擾收音機既, 無線電干擾有好多原因, 有啲電機及電子電器都好可能干擾收音機既, 如微波爐電磁爐等等, 就算你用兩架收音機靠近接收訊號都會干擾既, 如果附近有人用無線電對講機, 無線電遙控玩具, 甚至無線電控電動門都會干擾, 你唯有轉換地點聼收音機啦。

2010-03-19 17:26:49 補充：
能干擾收音機既唔係長天線，係收音機，任何收音機都會有高頻及中頻，只要有任何一架收音機既中頻夠強，就會影響或干擾其他既收音機，我講過就算你用兩架收音機靠近接收訊號都會干擾既，唔信你可以試試，方法如下：
將一架收音機調准接收某一個電台，用另外一架收音機(不要開聲)係旁邊慢慢既調來調去，當你調到某一個頻率(唔同第一架收音機既頻率)，你就會聽到干擾聲啦。