Set FROM email address for notifications

// http://www.gravityhelp.com/forums/topic/notifications-3
// change the 2 below to your form id if it's not form 2
add_action('gform_pre_submission_filter_2', 'set_from_email');
function set_from_email($form) {
    // change input_19 here to the field that contains the email VALUE for your technician
        $techemail = rgpost('input_19');
        $form['notification']['from']  = $techemail;
        $form['autoResponder']['from'] = $techemail;
        return $form;
}