雪花:加放大器 (this is the most easy way, from $2xx to $4xx, I heard that ?視寶 is quite good )
鬼影:比較難搞; if you use common antenna in your building, then u should ask management office to send a technician to help you, free of charge...
(if you use your own antenna, then 要try改天線方向for the best direction, need two people...)
if you try the above and cannot improve, and you find the TV quality of your neighbour is much better than yours, then 可能 接線 或 牆插 有問題