Secret Service VHF radios are set up as follows:

 Channel Designation
 1       BAKER
 2       CHARLIE

 3       MIKE
 4       TANGO
 5       OSCAR
 6       PAPA
 7       BAKER REPEATER (165.7875/164.4000)
 8       CHARLIE REPEATER (165.3750/166.4000)

Frequencies A through Z

 Alpha    32.2300   WHCA-Transportation (vans) (possible DC base)
 Baker    165.7875  USSS-Field Offices, President/VP/VIP security

 Charlie  165.3750  USSS-Field Offices/Protection, command post
                    coordination (Nationwide Primary)
 Delta    169.9250  WHCA-Marine Security Detachment, vans

 Echo     407.8500  WHCA-SAM Uplink (Air Force 1 phone patch ground
                    uplink)

 Foxtrot  415.7000  WHCA-SAM Downlink (Air Force 1 phone patch aircraft
                    downlink)
 Golf     166.4000  USSS-Field Offices
          165.7625  Input to 165.3750 repeaters
 Hotel    167.9000  WHCA-V.P. Staff/White House Garage
          165.6875
          166.2125  President/VP Security
 India    407.9250  USSS-Headquarters (Treasury Security Force)
          166.2000
 Juliet   170.0000  USSS-Paging/Camp David
 Kilo     167.8250  Duplex Phone-Pres Res/LBJ, WHCA
 Lima     168.7875  Duplex Phone-Pres Res/LBJ, WHCA (voice scramblers)
 Lavender 418.1250  WHCA-Transportation

 Mike     165.2125  USSS-Dignitary/Former Pres Protection, Counterfeit
                    Division
 November 166.7000  WHCA-White House Staff
 Oscar    164.8875  USSS-Presidential Protection Division (PPD), WHCA

 Papa     164.4000  USSS-Field Offices/Protection, input to 165.2125
                    repeaters
 Quebec   ---
 Romeo    166.4000  Input to 165.7875 repeaters
          164.4000  USSS-Repeater Outputs
 Sierra   166.5125  WHCA-White House Staff

 Tango    164.6500  USSS-Field Offices/Protection, Presidential/VP
                    Security
 Uniform  361.6000  AF-1 Communications
          165.0875
 Victor   164.1000  WHCA, Presidential/VP Protection
 Whiskey  167.0250  WHCA-Paging
 X-ray    ********  SEE BELOW
 Yankee   162.6875  WHCA-Presidential phone uplink or downlink
 Zulu     171.2875  WHCA-Presidential phone downlink or uplink

The Treasury Common frequency is 166.4625.

X-ray is the reserve frequency pool and is not Treasury Common. Frequencies
here are used whenever a new frequency is needed.

X-ray frequencies

164.7500
164.8000
165.2625
165.3375
165.4125
165.5125
165.6500
165.6875
165.8500
165.9000
166.0500
166.2000
166.5625
166.5875
166.6375
166.8000
167.9000

The most active frequencies used before and during a presidential or vice
presidential visit are Baker, Charlie, Mike, and Tango, as well as any
channel designated for use by the WHCA. The frequency used most as a
nationwide primary repeater channel is Charlie, followed by Baker. Former
presidents' security use Mike. Oscar is used for presidential protection
nationwide and Papa is used for White House perimeter patrols.

Pres Nighthawk Aircraft Fleet (HMX)

 Transport         46.7500
 Transport         375.0000
 VIP Transport Net 34.3500
 Command Post      142.7500
 Squadron Common   265.8000
 USMC helicopters  46.7000, 46.7500, 46.8000, 122.8500, 375.0000

Other Phone Patches

 Nationwide-2          407.4750  uplink
 Nationwide-2          415.8000  downlink
 Limousines (Local/DC) 407.4500  duplex
 Limousines (Local/DC) 408.2000  duplex

USSS Uniform Division (All repeaters use PL 103.5 Hz)

 Gray   418.3500/407.7500                         White House
 Orange 418.7750/414.9500                         White House
 Brown  414.8500/418.8000                         Foreign Missions
 Red    415.9750/419.7250                         Foreign Missions
 Silver 415.6500/419.1000                         Foreign Missions

 Yellow 414.6750/418.1500, 415.9500 WHCA          Foreign Missions Patrol
        ("Boardwalk")                             Primary

Training Division: Beltsville, MD

 Green                    415.7500/407.8750
 Black                    415.1000/418.3250
 Blue                     414.8000
 Violet                   415.8000
 Communications Division:
 Gold                     415.6750/419.0750
 Other:
 Lavender                 418.1250           WHCA Transportation
 White                    407.6750

Technical Security Division (Special Use)

 F-1 408.0000
 F-2 411.0000
 F-3 408.5000
 F-4 408.9750

NOTES: Frequencies in 407 Mhz band are used for agents' body radios with
"wristwatch" microphones.

WHCA stands for White House Communications Agency.

The PL used by the Secret Service is 103.5 Hz.

The above info was gathered from several sources. Not all sources agreed on
the same frequencies.
