Gestión y administración de elementos de combate

An updated Public Information File shall made available at all times to the NTC inspector or to any interested party. the Public Information File shall be kept on file at each broadcats station and shall contain the following:

a. A copy of the station license.

b. Documents as to mode of ownership whether partnership, corporation or single proprietorship including trade name as registered in the Department of Trade.

c. Documents on all changes of transmitter equipment, including the incorporated changes in the license and the corresponding of construction permits.

d. Copies of the program standards, the Technician Standards, the NTC compilation of laws, regulations, circulars and memoranda.

e. Evidence of membership in the KBP, or any other broadcaters organization.

10. ANNEXES

A. Prediction of Coverage

Figure 1. F(50,50) Field Strength Chart for FM Channels and Sliding scale for use with Figure 1.

Figure 2. Standard Pre-Emphasis Curve

Figure 3. Simple Form For Prediction of Service Area and Interference Studies.

ANNEX A

1. Prediction of coverage

A.1.1. All predictions of coverage made pursuant to this section shall be made without regard to interferences and shall be made only on the basis of estimated field strengths.

A.1.2. In predicting the distance to the field stregth contours, the F(50,50) field intensity chart (figure 1), shall be used. If the 50 percent field intensity is defined as that value exceeded for 50 percent of the time, this F(50,50) chart gives the estimated 50 percent field intensities exceeded at 50 percent of the locations in decibels above 1-microvolt per meter. The chart is based on an effective power of 1-kilowatt radiated from a halfwave dipole in free space which produces an unattenuated field strength at 1.6 kilometers of about 103 dB above 1-microvolt per meter (137.6 millivolts per meter).

A.1.3. To use the chart for other powers, the sliding scale associated with the chart should be trimmed and used as the ordinate scale. The sliding scale is placed on the chart with the appropriate graduation for power in line with the horizontal 40 dB line on the chart. The right edge of the scale is placed in line with the appropriate antenna height graduations, and the chart then becomes direct reading (in microvolt per meter and dB above 1 microvolt per meter for this power and antenna height.) Where the antenna height is not provided, the signal strength or distance is determined by the interpolation between the curves connecting the equidistant scale. Dividers may be used in lieu of the sliding scale. In predicting the distance to the field strength contours, the effective radiated power to be used is that in the horizontal plane in the pertinent direction. In predicting other field strengths over areas not in the horizontal plane., the effective radiated power to be used is the power in the direction of such areas; the appropriate vertical plane radiation pattern must, of course, be considered in determining this power.

A.1.4. The antenna height to be used with this chart is the height of the radiation center of the antenna above the average terrain along the radial in question. In determining the average elevation of the terrain, the elevations between 3 and 16 kilometers from the antenna site are employed. Profile graphs shall be drawn for eight radials beginning at the antenna site and extending 16-kilometers therefrom. The radials should be drawn for each 45 degrees of azimuth starting with True North. At least one radial must include the principal community to be served even though such a community may be more than 16-kilometers from the antenna site. However, in the event none of the evenly spaced radials include the principal community to be served, then one or more such radials are drawn in addition to the eight evenly spaced radials, such additional radials shall not be employed in computing the antenna height above average terrain. The profile graph should indicate the topography accurately for each radial, and the graphs should be plotted with the distance in kilometers as the abscissa and the elevation in meters above mean sea level as the ordinate. it is not necessary to take the curvature of the earth into consideration in this procedure as this factor is taken care of in the charts showing signal strength. The average elevation of the 13-kilometer distance between 3 and 16 kilometers from the antenna site should then be determined from the profile graph, for each radial. This may be obtained by averaging a large number of equally spaced points, by using a planimeter, or obtaining the median elevation (that exceeded for 50 percent of the distance) in sectors and averaging these values.

A.1.5. In cases where the terrain in one or more directions from the antenna site departs widely from the average elevation of 3 to 16 kilometers sector, the predicted method may be indicate contour distances that are different from what may be expected in practice. For example, a mountain ridge may indicate the practical limit of service although the prediction method may indicate otherwise.

Table 1. ALLOCATION OF FREQUENCIES FOR FM BROADCAST STATIONS

Channel-designation of FM broadcast frequencies are shown in the table shown in the table below.

Channel No. Frequency(MHz) Channel No.

Frequency(MHz)

201 88.1 251 98.1

202 88.3 252 98.3

203 88.5 253 98.5

204 88.7 254 98.7

205 88.9 255 98.9

206 89.1 256 99.1

207 89.3 257 99.3

208 89.5 258 99.5

209 89.7 269 99.7

210 89.9 260 99.9

211 90.1 261 100.1

212 90.3 262 100.3

213 90.5 263 100.5

214 90.7 264 100.7

215 90.9 265 100.9

216 91.1 266 101.1

217 91.3 267 101.3

218 91.5 268 101.5

219 91.7 269 101.7

220 91.9 270 101.9

221 92.1 271 102.1

222 92.3 272 102.3

b. FM Studio Layout

c. Block Diagram for FM Radio

d. GLOSSARY

FM Broadcast Terminology

Antenna Height Above Average Terrain (HAAT) – It is the height of the radiation center of the antenna above the terrain 3 to 16 kilometers from the antenna.

Antenna field gain – it is the ratio of the effective free space field intensity

produced at 1.6 km in the horizontal plane expressed in mV/m for 1 kW antenna input power to 137.6 mV/m.

Antenna power gain – it means the square of the ratio of the rms free space field strength produced at 1.6 km in the horizontal plane, in mV/m.

Center frequency – it is the average frequency of the emitted wave when modulated by using a sinusoidal signal.

Crosstalk – An undesired signal occurring in one channel caused by an electrical signal in another channel.

Effective radiated power (ERP) – it is the product of the transmitter power and the antenna power gain or the antenna field gain square.

Field intensity – it is the electric field intensity in the horizontal direction.

FM stereophonic broadcast – the transmission of a stereophonic program by a single FM broadcast station utilizing the main channel and stereophonic

subchannel.

Free space field intensity – it is the field intensity that would exist the point, in the absence of waves reflected from the earth or other reflecting objects.

Frequency swing – it means the instantaneous departure of the frequency of emitted wave from the center frequency resulting from the modulation.

Main channel – the band of frequency from 50 to 15000 Hz which frequency modulate the main carrier.

Multiplex transmission – it means the simultaneous transmission of two or more signals within a single channel.

Pilot subcarrier – it serves as a control signal for use I reception of FM stereophonic broadcasts.

Service Area – it refers to the area bounded by a field intensity that is equal or greater than the minimum value necessary to permit a desired reception quality in the presence noise and interference, an from which the RF Protection Ratio is extended.

Stereophonic Separation – it is the ratio of electrical signal caused in the right (or left) stereophonic channel, to the electrical signal caused in the right (or left) stereophonic channel, by the transmission of only a right (or left) signal.

Stereophonic subcarrier – it is the second harmonic of the pilot subcarrier frequency in which is employed in FM stereophonic broadcasting.

Stereophonic subchannel – the band of frequencies from 23 to 53 KHz containing the stereophonic subcarrier and its associated sidebands.

Operating frequency – the carrier frequency at any particular time.

Authorized frequency – the carrier frequency authorized by the authority.

Operating power – “Operating power” is the transmitting output power.

Maximum Rated Carrier Power – “Maximum Rated Power” Is the maximum power at which the transmitter can be operated satisfactorily and is determined by the design of the transmitter.

Authorized Operating Power – “Authorized operating power” is the power authorize by the authority.

Modulator stage – “modulator stage” means the last audio amplifier stage of the modulating wave which modulates a radio-frequency stage.

Modulated Stage – “modulated stage” means the radio frequency stage to which the modulator is coupled and in which the continuous carrier wave is modulated in accordance with the system of modulation and the characteristic of the

modulating wave.

Daytime – “daytime” the term refers to the period of time between 2200 Universal Time Coordinates (UTC) to 1000 Universal Time Coordinates (UTC) or 6:00 AM to 6:00 PM local standard time.

Nighttime – the term “nighttime” refers to the period of time between 1000

Universal Time Coordinates (UTC) to 2200 Universal Time Coordinates (UTC) or 6:00 AM to 6:00 PM local standard time.

Experimental Period – the term “Experimental Period” means that the time between 12 midnight to 5:00 AM local standard time or 1600 to 2100 Universal Time Coordinates (UTC)

Spurious Emission – the emission of any frequency outside of the assigned channel or authorized band of frequencies and tolerances allowed by these regulations. Emission outside the assigned channel, as a result of the modulating process, is not considered spurious, unless it is due to overmodulation.

Authority – the National Telecommunications Commission.

e. REFERENCES

Books

 Blake, Electronic Communication Systems (2^nd Edition)