These are the schematics to build a GSM jamming device, or more commnoly called a GSM jammer. It should be pretty easy to adatp the frequency to the desired band Seems like the third harmonic on the 800MHz is also able to jam WiFi ...
Open source WiFi, cellphone, GPS and RF jammer. Modifying a cheap portable ecllphone jammer. Phone lokos like pack of cigarettes and cell phone jammer that fits inside a pack of cigarettes. ...