I know the day is almost over but just seen your post if shes still not around you'll have them for next time. I did a quick search for secret service on the wiki and came up with this link
United States Secret Service - The RadioReference Wiki
I would make sure to have In scanner if anything.
Channel Frequency Description Tone
Baker 165.7875 Nationwide Commandpost BM 103.5 PL
Charlie 165.375 NW Primary/Command RM P25
Mike 165.2125 Foreign Heads of State BM 103.5 PL
Oscar 164.8875 President Protection BM P25
Papa 164.4 Technical Services Division BM 103.5 PL
Sierra 166.5125 Presidential Security BM P25
Tango 164.65 Vice President Protection BM 103.5 PL
