hello all, new to site would realy be greatfull for any help or views on following, i am in process of building home burglar alarm system and would like to know what device would activate a mobile gsm phone to ring a last dialed number, my other gsm phone that would allert me when my house alarm has been triggerd, was looking for device that i would be able to build myself and ad to alarm pannel, many thanks, cctv.