Maximum Transmit Power for channel 36 ,40,44 and 48

[KAVITA MATHUR]

Hi,

Chipset : AR9220 
RF module : WLM200NX and WLM200N5
Linux Kernel : 3.12
ath9k driver : backport4.4.2-1

With above combination , I have measured maximum transmit power 13 dBm for channel
36,40,44 and 48. While it is 20 dBm for channel 149 and other 5GHz band channels
 as well as for 2.4 GHz channels.

If I try to set txpower using iwconfig wlan0 txpower 20 , it gives no error.but it shows
only 13dBM.

How I can change the txpower for channel 36,40,44 and 48?

Please help me on this.

Thanks & Regards,
कविता माथुर Kavita Mathur 
वरिष्ठ अनुसंधान अभियंता  Senior Research Engineer 
सी-डॉट                      C-DOT
इलैक्ट्रॉनिक्स सिटी फेज़ I         Electronics City Phase I
होसूर रोड, बेंगलूरु               Hosur Road, Bengaluru – 560100
फोन  Ph 080-28529896
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