Allied Telesis AT-WNP300N - Manual (Page 10)

10 AT-WNP300N - IEEE802.11b/g/n 1T2R Wireless Fast PCI adapter - Installation Guide
LED State Description
Link Off The adapter is radio off.
On The adapter is connected
Fast Blinking The adapter is disconnected
Activity Off The adapter is radio off.
Slow Blinking The adapter is disconnected or connected
Fast Blinking Data transmitting