FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION

TITLE: AM TOWER STRUCTURES IN FLORIDA - AUGUST 2018

Geodataset Name:       AMTOW_AUG18
Geodataset Type:       SHAPEFILE
Geodataset Feature:    Point
Feature Count:         250
GENERAL DESCRIPTION:
This dataset contains the spatial extent of AM tower structures in the state of Florida. AM stands for "Amplitude Modulation", which refers to the means of encoding the audio signal on the carrier frequency. In many countries, AM radio stations are known as "medium wave"(MW) stations. AM stations are also sometimes referred to as "standard broadcast stations", since AM was the first form used to transmit broadcast radio signals to the public. AM towers are unique in that AM stations have different operations for daytime and nighttime operation. This is because AM signals go further at night, due to atmospheric changes. Usually day and night operations are at the same site, but some may use different sites. These daytime and nighttime operations lead to duplicate records at the same location. Because we are only interested in tower locations and not individual AM stations for this particular dataset duplicate records representing day/night stations were removed .This is an update to the amtow_feb17 layer.
DATA SOURCE(S):                    Federal Communications Commission
SCALE OF ORIGINAL SOURCE MAPS:     Unknown
GEODATASET EXTENT:                 State of Florida
PUBLICATION DATE: 20180814 TIME PERIOD OF CONTENT: 20180814 DOWNLOAD LINK: http://www.fgdl.org/metadataexplorer/explorer.jsp

FEATURE ATTRIBUTE TABLES:

Datafile Name: AMTOW_AUG18.DBF
ITEM NAME WIDTH TYPE
OBJECTID
4 OID
Shape
4 Geometry
CALLSIGN
12 String
FREQUENCY
10 String
SERVICE
3 String
CLASS
3 String
STATUS
7 String
CITY
25 String
STATE
3 String
COUNTRY
3 String
FILENUM
20 String
FACID
11 String
LAT
15 String
LON
15 String
LICENSEE
100 String
LATDD
8 Double
LONDD
8 Double
MGRS
15 String
GOOGLEMAP
100 String
DESCRIPT
100 String
FGDLAQDATE
36 Date
AUTOID
4 Integer

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Item
Item Description
OBJECTID Internal feature number.

Shape Feature geometry.

CALLSIGN A combination of letters and numbers that identify an FCC license.

FREQUENCY AM station frequncy. AM stations occupy the frequencies of 540 kHz to 1700 kHz. These stations are allocated on a non-interference basis.

SERVICE Service type. AM for all.

CLASS FCC given code. The AM band frequencies are divided into three categories: Clear, Regional, and Local channels. The allowable classes depend on a station's frequency, in addition to other variables. On the Clear channels certain stations are specifically classified as Class A stations or as Class B stations. The other stations have their class determined by the frequency.
A = Class A station is an unlimited time station (that is, it can broadcast 24 hours per day) that operates on a clear channel. The operating power shall not be less than 10 kilowatts (kW) or more than 50 kW.

B = Class B station is an unlimited time station. Class B stations are authorized to operate with a minimum power of 0.250 kW (250 watts) and a maximum power of 50 kW. (If a Class B station operates with less than 0.250 kW, the RMS must be equal to or greater than 141 mV/m at 1 km for the actual power.) If the station is authorized to operate in the expanded band (1610 to 1700 kHz), the maximum power is 10 kW

C = Class C station is an unlimited time station that operates on a local channel. The power shall not be less than 0.25 kW nor more than 1 kW. Class C stations that are licensed to operate with 0.100 kW may continue to operate as licensed

D = A Class D station operates either daytime, limited time, or unlimited time with a nighttime power less than 0.250 kW and an equivalent RMS antenna field less than 141 mV/m at 1 km for the actual power. Class D stations shall operate with daytime powers not less than 0.250 kW nor more than 50 kW. NOTE: If a station is an existing daytime-only station, its class will be Class D.


STATUS Tower status.
ADD = Proposal to add a channel

APP = Application

APPDID = Application denied by initial Decision in hearing

APPGID = Application granted by initial Decision in hearing

CP = Construction Permit

CP MOD = Modification of a construction permit

DEL = Proposal to delete a channel

LIC = License


CITY City location of "LICENSEE".

STATE State location of "LICENSEE".

COUNTRY Country location of "LICENSEE".

FILENUM The FCC-assigned file number of the application.

FACID Facility ID.

LAT The exact geographic location latitude of the structure in degrees (e.g., 42), minutes (e.g., 13'), and seconds (e.g., 10").

LON The exact geographic location longitude of the structure in degrees (e.g., 42), minutes (e.g., 13'), and seconds (e.g., 10").

LICENSEE Company or organization that holds the legal license from the Federal Communications Commission.

LATDD Geographic location (latitude) in decimal degrees.

LONDD Geographic location (longitude) in decimal degrees.

MGRS Military Grid Reference System (MGRS) Coordinate of the Facility. The MGRS is the geocoordinate standard used by NATO militaries for locating points on the earth. The MGRS provides a means to represent any location on the surface of the Earth using an alphanumeric string. Hierarchical references are based on the Universal Transverse Mercator (UTM) coordinate system. The MGRS is used for the entire earth. http://mgrs-data.org/

GOOGLEMAP Webpage hyperlink to location in Google Maps.

DESCRIPT GeoPlan added field based on LICENSEE.

FGDLAQDATE The date GeoPlan aquired the data.

AUTOID Unique ID added by GeoPlan


USER NOTES:
This data is provided 'as is'. GeoPlan relied on the integrity
of the original data layer's topology
This data is provided 'as is' by GeoPlan and is complete to our
knowledge.
GeoPlan relied on the integrity of the attribute information within
the original data.

Serve as base information for use in GIS systems for general planning, 
analytical, and research purposes. It is not intended for engineering work 
or to legally define reservation boundaries, FCC licensee data or FCC market 
boundaries.

This data is provided 'as is' and its horizontal positional accuracy
has not been verified by GeoPlan

This data is provided 'as is' and its vertical positional accuracy
has not been verified by GeoPlan

Any use of trade, product, or firm names is for descriptive purposes only and does 
not imply endorsement by the U.S. Government or the Federal Communications 
Commission (FCC). No warranty expressed or implied is made by the FCC as to the 
accuracy of the data and related materials. The act of distribution shall not 
constitute any such warranty, and no responsibility is assumed by the FCC in the 
use of this data, or related materials.

The Florida Geographic Data Library is a collection of Geospatial Data
compiled by the University of Florida GeoPlan Center with support from
the Florida Department of Transportation. GIS data available in FGDL is
collected from various state, federal, and other agencies (data sources)
who are data stewards, producers, or publishers. The data available in
FGDL may not be the most current version of the data offered by the
data source. University of Florida GeoPlan Center makes no guarantees
about the currentness of the data and suggests that data users check
with the data source to see if more recent versions of the data exist.

Furthermore, the GIS data available in the FGDL are provided 'as is'.
The University of Florida GeoPlan Center makes no warranties, guaranties
or representations as to the truth, accuracy or completeness of the data
provided by the data sources. The University of Florida GeoPlan Center
makes no representations or warranties about the quality or suitability
of the materials, either expressly or implied, including but not limited
to any implied warranties of merchantability, fitness for a particular
purpose, or non-infringement. The University of Florida GeoPlan Center
shall not be liable for any damages suffered as a result of using,
modifying, contributing or distributing the materials.

A note about data scale: 

Scale is an important factor in data usage.  Certain scale datasets
are not suitable for some project, analysis, or modeling purposes.
Please be sure you are using the best available data. 

1:24000 scale datasets are recommended for projects that are at the
county level.
1:24000 data should NOT be used for high accuracy base mapping such
as property parcel boundaries.
1:100000 scale datasets are recommended for projects that are at the
multi-county or regional level.
1:125000 scale datasets are recommended for projects that are at the
regional or state level or larger.

Vector datasets with no defined scale or accuracy should be
considered suspect. Make sure you are familiar with your data
before using it for projects or analysis. Every effort has been
made to supply the user with data documentation. For additional
information, see the References section and the Data Source Contact
section of this documentation. For more information regarding
scale and accuracy, see our webpage at:
http://geoplan.ufl.edu/education.html

REFERENCES:
Federal Communications Commission:
http://www.fcc.gov/

FCC Wireless Telecommunications:
https://www.fcc.gov/wireless-telecommunications#block-menu-block-4

FCC Radio Service Code List:
http://www.perconcorp.com/documents/rscode.pdf

Universal Licensing System Glossary:
http://wireless.fcc.gov/uls/documentation/pa_ddef50.pdf

AM Station Classes: 
https://www.fcc.gov/media/radio/am-clear-regional-local-channels

DATA LINEAGE SUMMARY:
In 2012, the FCC stopped releasing its data as spatial data.  Downloaded AM 
Towers using the AM Query Broadcast Station Search.  Selected only Florida 
stations with an output of Text file (no delimiters / no links).  Downloaded from 
(https://www.fcc.gov/media/radio/am-query) in February 2017.  Copied all 
records and pasted them into a text file.  Saved as AMTOWER.txt. 

- Opened and formatted AMTOWER.txt in Excel.  Added field names using 
  amtow_jun12 and Data arrangement for Text file outputs 
  (https://www.fcc.gov/media/radio/am-fm-tv-textlist-key).  Saved coordinate 
  fields as LATD, LATM, LATS, LATDIR, LOND, LONM, LONS, and LONDIR
- Saved as .csv file
- Opened .csv in ArcMap and exported to a dbase table
- Added LATDD and LONDD fields using type = double. These fields will be 
  used to house the coordinates in decimal degrees.  These field names were
  chosen to mimic the coordinate fields in amtow_jun12.
- Used field calculator to convert coordinate fields from DMS to DD. The 
  equation for latitude (LATDD) was:
	( [LATS] /3600) + ( [LATM] /60) + [LATD]
  The equation for longitude (LONDD) was:
	( [LONS] /3600) + ( [LONM] /60) + [LOND]
- Generated XY data using the LATDD and LONDD fields.  The projection
  was defined as WGS 1984.

AMTOW shapefile
-There were originally 444 records when received from the FCC. AM towers are
 unique in that AM stations have different operations for daytime and nighttime
 operation. This is because AM signals go further at night, due to atmospheric 
 changes. Usually day and night operations are at the same site, but some may use
 different sites. These daytime and nighttime operations lead to duplicate records at
 the same location. Because we are only interested in tower locations and not 
 individual AM stations for this particular dataset 194 duplicate records were 
 removed leaving 250 records.
- Projected the event layer to Albers_Harn using project tool and exported out as 
  shapefile
- Deleted all fields not present in amtow_jun12
- Added descript field based on LICENSEE 
- Added FGDLAQDATE based on the date GeoPlan acquired the data
- Added a LAT and LON field based on combination of LATD, LATM, LATS, 
  LATDIR, LOND, LONM, LONS, and LONDIR then deleted those field because
  they are not present in the previous AMTOW shapefile
- Restructured table and uppercased all fields

Note:
When the FCC generated this data set spatially in the past they limited the 
lat/long fields to 4 decimals. Now that we are generating the spatial locations 
the decimals have been left to the default value of the field type of double. 
The result is a visible shift of 30-36 meters. Although the new points should 
be more accurate most AM tower locations are actually a collection of multiple 
towers spread several hundred feet apart so no single point will accurately 
reflect AM tower locations.
Process Date: 20180817

Metadata imported. Process Date: 20180828
Dataset copied. Process Date: 20180828
MAP PROJECTION PARAMETERS:

Projection                          ALBERS
Datum                               HPGN
Units                               METERS
Spheroid                            GRS1980
1st Standard Parallel               24  0  0.000
2nd Standard Parallel               31 30  0.000
Central Meridian                   -84 00  0.000
Latitude of Projection's Origin     24  0  0.000
False Easting (meters)              400000.00000
False Northing (meters)             0.00000

DATA SOURCE CONTACT (S):

Name:
Abbr. Name:
Address:


Phone:

Web site:
E-mail:
Contact Person:
         Phone:
        E-mail:
Federal Communications Commission
FCC
445 12th St. SW
Washington, D.C.
20554
888-225-5322

https://www.fcc.gov/media/radio/am-query fccinfo@fcc.gov

FGDL CONTACT:
Name:                   FLORIDA GEOGRAPHIC DATA LIBRARY
Abbr. Name:             FGDL
Address:                Florida Geographic Data Library
                        431 Architecture Building
                        PO Box 115706
                        Gainesville, FL  32611-5706
Web site:               http://www.fgdl.org

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