Now how would a photo ticket be able to discern the VIN number of your vehicle? Same thing for the radar device. You know from looking at the photo whether it was your car or not, I bet. You need to make a discovery request request of the DA to get information about the radar device and it's maintenance records. If you plan to fight this seriously you need a traffic attorney.
If you sign the waiver of service and mail it back, you validate the ticket. If you don't do that, some other service must occur.
"Summons and complaint may be served by first-class mail along with two copies of notice and acknowledgment of receipt of summons and complaint and postpaid return envelope, but service is not complete until the acknowledgment of receipt is executed." 16 A.R.S. Rules Civ.Proc., Rule 4.1(c), (c)(1, 2).
Essentially, that means the ticket -- which contains a court summons -- must be hand-delivered to you or a resident of your home if you do not validate it by mailing it back ( i.e. *service is not complete until the acknowledgment of reciept is executed.)
You need a lawyer. Check with an Arizona lawyer in your locale to discuss more of the details. I practice in Illinois.
Good luck to you.
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