How do I get the card to use monitor mode?
New Code
To create a monitor mode VAP, see: UserDocs/MonitorModeInterface. After that, it won't be necessary to use the command iwconfig ath0 mode monitor.
The nice thing about the vap code is that you can just add another vap in monitor mode and it will act just like the rawdev used to - you can send packets to that device, and they will go out like they would on the old rawdevice.
Old Code
To set the driver into monitor mode, issue the following commands:
iwpriv ath0 mode 2
This locks the card to 802.11b operation.
iwconfig ath0 mode monitor channel XX
Replace the XX with the channel you want to monitor… and bring the interface up.
ifconfig ath0 up