If you have been able to connect your computer, phone, etc., to your home wifi without ever entering a password, then you might have an UNSECURED home wifi. If there is no password or passphrase then anyone can connect to it and see all your devices and traffic, which is why it's a bad idea, but maybe that is what you have. Or have you used the WPS method (push a button on the device and on the router and they "talk" to each other to set the password for the conection)?
If we pretend for the moment that there is no password, i.e., no encryption, have you tried connectng the Brennan by leaving the password field entirely blank?