[99-25 NPRM] Appendix B

This appendix sets forth the minimum distance separations between the proposed classes of low power FM stations and existing full service FM stations. The first number in each box indicates the minimum distance necessary to ensure that the low power station would not create interference. The second number corresponds to the distance necessary to ensure that the low power station would not receive interference. The tables also show what distances would be necessary for co- and first-adjacent channel low power stations to provide interference protection to each other.

Distance separations between domestic facilities were based on the sum of the protected F(50,50) contour radius and the appropriate F(50,10) interfering contour radius as calculated in accordance with 47 C.F.R. '' 73.313 and 73.333. Full service domestic stations were assumed to operate at ' 73.211 maximum facilities. ¹¹⁸ Low power stations were assumed to utilize the maximum defined for the proposed class. Class B stations were protected to the 54 dBu F(50,50) contour and Class B1 stations are protected to the 57 dBu F(50,50) contour. All other classes (including low power) were protected to the 60 dBu F(50,50) contour. The interfering contours were determined using the following desired-to-undesired (D/U) signal ratios: co-channel, +20 dBu; first-adjacent channel,+6 dBu; second-adjacent channel (reserved band), -20 dBu; second- and third-adjacent channel (commercial band), -40 dBu. IF (intermediate frequency) spacings were calculated to prevent overlap of the 91 dBu F(50,50) (36 mV/m) contours of both stations.

Finally, minimum distance separations were calculated for low power stations operating within 320 kilometers of the common borders with either Canada or Mexico. The spacings in the Canadian and Mexican border zones were based on the maximum protected/interfering contours of the foreign allocations vs. the interfering/protected contours of the domestic low power stations, as required by Section 5 of the Canada-United States FM Broadcasting Agreement and Section 3 of the Mexico-United States FM Broadcasting Agreement, respectively. Any low power station within 320 km of either border would require coordination with the appropriate government.

CLASS LP1000

Assuming 1000 watt effective radiated power (ERP) at 60 meters antenna height above terrain (HAAT) 60 dBu F(50,50) protected contour extends 14.2 km

MINIMUM DISTANCE SEPARATION (KM) NECESSARY TO: CAUSE NO OVERLAP/RECEIVE NO OVERLAP

CLASS LP1000 WITHIN 320 KM OF THE CANADIAN BORDER

CLASS LP1000 WITHIN 320 KM OF MEXICAN BORDER

CLASS LP100

Assuming 100 watt effective radiated power (ERP) at 30 meters antenna height above terrain (HAAT) 60 dBu F(50,50) protected contour extends 5.2 km

MINIMUM DISTANCE SEPARATION (KM) NECESSARY TO: CAUSE NO OVERLAP/RECEIVE NO OVERLAP

CLASS LP1000 WITHIN 320 KM OF THE CANADIAN BORDER

CLASS LP1000 WITHIN 320 KM OF MEXICAN BORDER

MICRORADIO CLASS

Assuming 1 watt effective radiated power (ERP) at 30 meters antenna height above terrain (HAAT) 60 dBu F(50,50) protected contour extends 1.8 km

MINIMUM DISTANCE SEPARATION (KM) NECESSARY TO: CAUSE NO OVERLAP/RECEIVE NO OVERLAP

MICRORADIO CLASS WITHIN 320 KM OF THE CANADIAN BORDER

MICRORADIO CLASS WITHIN 320 KM OF MEXICAN BORDER

Footnotes

118 Class D stations are assumed to operate with 85 watts ERP at 30 meters HAAT. This yields a 60 dBu that extends 5.4 km (just below the minimum required for a Class A station).

119 In accordance with the Canada-United States FM Broadcasting Agreement, Canadian Class C stations are protected to the 58 dBu contour. All other Canadian stations are protected to the 54 dBu contour.

120 In accordance with the Mexico-United States FM Broadcasting Agreement, Mexican Class B stations are protected to the 54 dBu. Mexican Class B1 stations are protected to the 57 dBu contour. All other classes are protected to the 60 dBu contour.

121 Pursuant to the Mexico-United States Broadcasting Agreement, both the second- and third-adjacent channel spacings are based upon a -40 dBu D/U ratio.