RFID Radio-frequency identification
<p>Jan 06, 2013 02:16 PM
 
see tutorial in HowStuffWorks  below
 
key is page 4 Active, Semi-passive and Passive RFID Tags
 
Active/ semi-active means it has a battery and higher powered RF xmtr
(can go several hundred feet (eg railcar )for expensive goods).
 
Passive means its powered by the readers RF beam... can go perhaps 20 feet
cheap:  7 to 20 cents per tag  for cheap products.
 
also read near field communic;
 
aug 2006  electronic passports from gov.
 
read animal and human chipping
 
chip farm animals
 
chips => sarcomas in rats and mice.
 
Verichip
 
 
 
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