Ottawa Canada Dear David and List: You said entering the numbers: *3001#12345# then pressing the Call button on an IPhone brings up the Field Test Mode which displays signal strength in dB instead of bars. Well I did this and my IPhone 4S with IOS 7.02 displayed: Error processing request: Unknown error. Does this key sequence work on all models of IPhone or only some? Thanks Brian ************ You are subscribed to the mac4theblind mailing list. The url for this list, where one can unsubscribe or make any changes to their list subscription is: //www.freelists.org/list/mac4theblind The list archive is located at //www.freelists.org/archive/mac4theblind/ All emails intended for the list owner can be sent to: john@xxxxxxxxxxxxxxxxxx