FlyerTalk Forums - View Single Post - The Definitive "Delta - TSA Pre-Check" thread
Old Sep 22, 12, 8:48 am
  #784  
bennos
 
Join Date: Dec 2008
Location: Hands of Fate
Programs: MR LT(!)TE, DL DM->PM MM, HTZ PC, 2V Fanboi, CBP GE, Uber Gold
Posts: 4,741
Originally Posted by gooselee View Post
The triple beep is triggered by something within the BP barcode. I believe a TSO can still deny someone access to PreCheck screening even if they've received the three beeps, but for the scanner itself, it's literally searching for a character and then audibly/visibly reporting whether or not it's present.
Do you have familiarity with the equipment? It seems easy to imagine a way to program such a device to add a random check after the character is found.

Code:
if(precheck_bit_found) {
  if(rand(0,1) < .99) {
    beep(3);
  } else {
    beep(1);
  }
} else {
  beep(1);
}
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