Welcome to RR.com Civil!
Please learn to use the database link at the top of every page here at this site...the database link takes you to the Nationwide US page which if you click on the State of NC will take to you to the State of NC page...now click on the Guilford County link...then click on the "Greensboro/Guilford County Public Safety Trunked System" link...that will take you to accurate information about the Greensboro/Guilford County Trunked system which includes accurate talkgroups for the Greensboro Police Department...since I am in a good mood this evening here is a direct link to the system:
http://www.radioreference.com/modules.php?name=RR&sid=291
Please search the database thoroughly in the future before posting as that is where the frequency/talkgroup information is located!
Since I have answered your question I am going to go ahead and close this thread...
Happy Monitoring!
Marshall KE4ZNR