Wireshark-users: [Wireshark-users] Why I cannot capture beacon frame

From: 清 廖 <liaoqing24@xxxxxxxxxxxx>
Date: Wed, 19 Jan 2011 22:10:10 +0800 (CST)
Hi all,
I used hostapd to change the AR9233 NIC to master mode. Then I use Wireshark to capture monitor wlan0.But I've only captured Probe Reques. I don't know what is wrong. I want to capture beacon frames, could you please help me? Thanks a lot.

These is record of mon.wlan0:

1    0.000000    Apple_59:b1:68    Broadcast    IEEE 802.11    Probe Request, SN=1821, FN=0, Flags=........, SSID="sMobileNet"
2    0.010399    Apple_59:b1:68    Broadcast    IEEE 802.11    Probe Request, SN=1822, FN=0, Flags=........, SSID="sMobileNet"
3    0.865638    Intel_d5:33:62    Broadcast    IEEE 802.11    Probe Request, SN=3011, FN=0, Flags=........, SSID=Broadcast
4    0.868659    Intel_d5:33:62    Broadcast    IEEE 802.11    Probe Request, SN=3012, FN=0, Flags=........, SSID=Broadcast
5    0.871771    Intel_d5:33:62    Broadcast    IEEE 802.11    Probe Request, SN=3013, FN=0, Flags=........, SSID=Broadcast
6    0.874849    Intel_d5:33:62    Broadcast    IEEE 802.11    Probe Request, SN=3014, FN=0, Flags=........, SSID=Broadcast
7    1.284201    Intel_d5:33:62    Broadcast    IEEE 802.11    Probe Request, SN=3032, FN=0, Flags=........, SSID=Broadcast

Best,
Qing