A capacidade de mudar o canal é uma função do driver do adaptador wifi. Alguns podem, alguns não podem.
Se o seu puder, você o encontrará nas propriedades do adaptador wifi.
Press the Windows logo and "R" keys simultaneously to display the "Run" dialog box. Type "devmgmt.msc" without quotation marks into the box and press "Enter." The Windows device manager will appear.
Double-click "Network Adapters" to expand the category.
Right-click your wireless network adapter and click "Properties."
Click the "Advanced" tab, then click "Ad Hoc Channel 802.11" under "Property" on the left side of the window.
Use the arrows on the right side of the window to change the channel. Make sure that you and your ad hoc networking partner select the same channel.
Click "OK" to save the change, then close the device manager.
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