. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .In reply refer to:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1800B3-DEB

St. Croix Wireless, Inc.
P.O. Box 25016
St. Croix, VI 00824

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .In re: WAVI; Christiansted, VI
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . St. Croix Wireless Co., Inc.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BPH-930402IE

Gentlemen:

This letter is in reference to the above-captioned application for construction permit for station WAVI, Christiansted, VI. This application, filed by the permittee of WAVI, St. Croix Wireless Co, Inc. ("Wireless"), proposes Class B facilities on Channel 228, as authorized by Docket 91-296.

The site proposed for WAVI in this application is located 167.4 km from first-adjacent channel Class B station WZNT, San Juan, PR. This spacing is 1.6 km less than the 169 km minimum spacing required under 47 CFR § 73.207. Recognizing this, Wireless has requested processing under the contour overlap rule, 47 CFR § 73.215. Further, it has requested waiver of that portion of the rule which defines the protected and interfering contours to be employed (47 CFR § 73.215(a)(1)).

Because of the greater antenna heights permitted for stations in Puerto Rico and the Virgin Islands, the contour overlap provisions of § 73.215 generally fail as an effective alternative to the spacing criteria of § 73.207. This is because, in many circumstances, contour overlap already exists, even between fully spaced stations. See Footnote 1. Thus, use of the contour overlap rules pursuant to § 73.215 does not afford relief for many Puerto Rico or Virgin Islands stations seeking to use a short-spaced site. To address this matter, upon reconsideration the Commission adopted rule 47 CFR § 73.215(a)(4) which permits stations in Puerto Rico and the Virgin Islands the alternative of showing that the 1 mV/m (60 dBu) contour from the short-spaced site is not extended past the present 1 mV/m location. See the Memorandum Opinion and Order in MM Docket 87-121, 6 FCC Rcd 5356, 56 Fed. Reg. 57290 (1991), paragraphs 51-52. However, in the present instance § 73.215(a)(4) also provides no relief. See Footnote 2.

Wireless has requested that subsection 73.215(a)(1) be waived to permit an alternate method to be employed. Wireless notes that the maximum reference facilities for Class B stations in Puerto Rico and the Virgin Islands is 50 kW effective radiated power (ERP) and 472 meters antenna height above average terrain (HAAT). Assuming two first-adjacent channel Class B stations at the minimum spacing specified in 47 CFR § 73.207 (169 km), and using the 6 dB protection ratio for first-adjacent channel stations from § 73.215(a)(2), Wireless found that the actual contour protected by this spacing is the 63 dBu contour, and that the corresponding interfering contour is the 57 dBu contour. Employing the 63 dBu contour as the standard of protection, and using the 57 dBu contour as the interfering contour, Wireless determined that neither WAVI nor WZNT will receive interference from the other pursuant to the contour overlap provisions of § 73.215 (except §§ 73.215(a)(1) and (a)(4)). Consequently, Wireless submits that use of this method and waiver of the rule is warranted, since neither station wo uld receive interference beyond that contemplated by the existing spacing rules.

We concur with Wireless' technical findings. Furthermore, we also note that this procedure does not affect WZNT's right to achieve maximum Class B facilities (50 kW ERP/472 meters HAAT) from its present transmitter site under § 73.207. As Wireless indicated, this procedure affords WZNT the same protection which it presently receives under the spacing rule (§ 73.207). Finally, by using the provisions of § 73.215 as modified to account for the higher HAAT limits specified in the rules for Puerto Rico and the Virgin Islands, Wireless' proposal would comply with the original intent of the rule, which is to afford stations the flexibility of considering short-spaced transmitter sites while protecting other stations from interference in excess of that which may occur under the Commission's spacing rules. Accordingly, we find that waiver of 47 CFR § 73.215(a)(1) is warranted; the requested waiver IS HEREBY GRANTED. Application BPH-930402IE, being otherwise acceptable for filing, IS HEREBY GRANTED. This action is taken pursuant to 47 CFR § 0.283.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sincerely,

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Larry D. Eads, Chief
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audio Services Division
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mass Media Bureau

6 kW ERP / 240 meters HAAT -- Class A
25 kW ERP / 150 meters HAAT -- Class B1
50 kW ERP / 472 meters HAAT -- Class B

All contours above in dBu --------Uniform Terrain Assumed

Footnotes:

Footnote 1: On the mainland, the spacing rules in 47 CFR § 73.207 are designed so that two stations of maximum class at minimum separation will not cause interference to either station's protected service contour (54 dBu for Class B stations, 57 dBu for Class B1, and 60 dBu for all other classes). However, because of the greater antenna heights permitted for stations in Puerto Rico and the Virgin Islands, the protected and interfering contours extend further, and often overlap. The attached table shows the actual protected and interfering contours for Class A, B1, and B stations under § 73.207 (assuming maximum facilities for each station and uniform terrain) in Puerto Rico and the Virgin Islands.

Footnote 2: Because WAVI was initially authorized Class B operation in Docket 91-296, the station has no existing 1 mV/m Class B contour to compare the proposed 1 mV/m contour against. Commission policy does not allow a § 73.215 applicant to compare its proposed protected or interfering contour against a hypothetical or unbuilt construction permit's protected or interfering contour; such proposals can only be evaluated against an existing contour, where the contour in question is actually being generated by an operating station. See Letter from Larry D. Eads, Chief, Audio Services Division to Interstate Broadcasting Systems of Arizona, Inc. (KRDS-FM), dated January 5, 1993. Without a reference to an existing contour, a station cannot apply Paragraph 54 of the Memorandum Opinion and Order in MM Docket 87-121, supra, which gives applicants the right to maintain existing overlap. Thus, WAVI's proposal to specify a Class B 1 mV/m contour for the first time does not comply with § 73.215(a)(4).

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Updated December 13, 1996