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Appendix AAPPENDIX A VIR JAMES P. C. TIMOTHY C. CUTFORTH P.E., DIRECTOR OF ENGINEERING -BROADCAST ENGINEERING CONSULTANTS y 965 S. IRVING ST — DENVER, CO • 80219 (303) 937-1900 Mr. Tim Orthameyer Morrison - Maierle, Inc. P. 0- Box 6147 Helena, Montana Dear Mr. Orthameyer; DI RECTIONAI_ ANTENNAS AM - FM -TV APPLICATIONS PROOFS FIELD MEASUREMENTS AUDIO AND RF ENGINEERING EMERGENCY REPAIR Concerning radio station KGEZ Kalispell, Montana. Engineer Timothy Cutforth P.E. traveled to Kalispell to inspect the KGEZ facility to determine its present condition with the following results: KGEZ EQUIPMENT SERVICEABILITY The present facilities were somewhat dated but quite solid and in apparent good repair. The transmitter and antenna phasor system were manufactured in about 1982 and appeared clean and well maintained. The antenna tuning units at the tower bases were clean and in good condition. The tower base tuning enclosures were plywood and wood frame construction, well painted but very basic. The towers were vintage 1954 solid rod galvanized steel guyed towers with about 25 ft of tower freestanding above the last guy wire. The guy wires were very large diameter and were insulated with ceramic "Johnny ball" type insulators at appropriate intervals as well as at the tower and the guy wire anchor points. The antenna feedline cables, sample line cables, and electrical wiring for the tower lights are installed elevated above the surface in plastic pipe. In some areas trenches have been dug and the cables are in the process of being buried. The antenna feedlines are vintage 1982 heliax style 7/8" cable. The antenna sample lines are 75 Ohm cable TV type 3/8" aluminum lines. The antenna ground radials appeared to be properly buried and in good order with the exception of some damage adjacent to the west tower caused by recent improper weed control methods - Member AFCCE -2- The system appeared to be operating within FCC standard tolerances and the FCC monitor points have a history of good stability in most weather conditions. Overall the system appeared to be in good working order and suitable for continued use for the purpose intended. PART 77 SURFACE PENETRATIONS On reviewing the Kalispell City Airport Preliminary Part 77 Airspace drawing it is clear that the existing KGEZ towers penetrate the horizontal surface for the existing runway and the present 20:1 approach slope for the existing runway length. The ultimate runway layout would have the KGEZ towers penetrating these surfaces by an apparent 108 ft and 173 ft respectively. PROPOSED REMEDIES TOWER HEIGHT REDUCTION Because of the large penetrations of the FAA Part 77 surfaces a reduction of tower height of greater than 100 ft would be required for each of the two towers. No standard tower antenna can achieve FCC standard minimum efficiency at a frequency of 600 kHz when shortened to the height needed to clear the FAA designated surfaces. Standard top loading technology to artificially extend the effective height of the tower cannot make up for this much tower height reduction. The Paran antenn is an alternate antenna technology to the standard tower antenna which have already been proven to be useable for.nondirectional AM broadcasting use but to date none have been filed for use in a directional antenna in the United States. I have requested the FCC staff to provide additional guidance on whether such new technology antennas can be reasonably authorized for use with a directional antenna in the AM broadcast service. The FCC staff has responded that they will license any antenna that we can show will work. The FCC construction permit application will however have to have a full derivation of the antenna characteristics so it will require about double the work of preparing a more normal application filing involving standard towers. VIR JAMES PC. • BROADCAST ENGINEERING CONSULTANTS. 965 S. !RWNG ST. • DENT . CO =0 i9 • PHONE I v�l �jI ;- --3- Construction of a Paran antenna system replacement for the KGEZ array would require replacement of the present towers each with•a Paran antenna consisting of four one hundred foot tall towers located at the corners of a one hundred foot square. The phasing system should be replaced for efficiency in installing the new system because of the dramatic improvements in design predictability since the old one was built. The tuning houses will need to be replaced since they will not be located in the right place to feed the Paran antennas. The ground system will need to be reconfigured around the new Paran antennas. The cables should likewise be replaced to minimize interruption of the operation. •The transmitter and sampling system likewise should be duplicated to allow initial setup of the new system while the old system remains operational. Since it will not be necessary to purchase land this may well be the most cost effective alternative. The obvious costs of installing a Paran style antenna as a replacement for the KGEZ towers and transmitting equipment: 1) 5kW transmitter $42,000 2) Antenna Phasing system $35,000 3) 100 ft towers (8 required), installed $15,000 each 4) buried radial ground system with installation approx 98,000 ft of wire $23,000 5) control, lighting, RF and monitoring cables comparable to present layout $45,000 6) RF Monitoring and audio processing equipment $25,000 RELOCATION OF TOWERS The FCC requires that any relocation of the KGEZ towers be such that the city'of Kalispell receives a specific defined signal strength for daytime and nighttime. Because of the greater daytime power and the high level of interference in the nighttime, the nighttime city grade coverage requirement is the most difficult to meet of the two. Anywhere the nighttime system can provide city grade quality signal over Kalispell, the daytime system will most certainly meet the requirements. Therefore I have prepared an allowable site area map showing where the present nighttime system could be relocated to meet the FCC city grade coverage requirement for nighttime. That map is attached as Exhibit E-6B. I/IR JAMES P.C. • BROADCAST ENGINEERING CONSULTANTS • SF-5 5. #RVING ST. • DENVER. CO 0219 • PHONE !3C3%! -4- The siting requirements for an Am directional array include adequate land to include the buried ground system around each tower with level land where the tower bases can be constructed within 10 ft of the same vertical elevation. Three phase power should be available nearby. A minimum tower siting land requirement for the present directional array is attached as Exhibit E--7. Radio station operations cannot be practically interrupted to move the existing equipment so it will be necessary to duplicate the facility to move it without extensive interruption of the daily broadcast schedule. Costs for -relocation will include land acquisition, site preparation, installation of utilities, and duplication of the transmitter building, transmitting towers and transmitting equipment at the new site. The obvious costs are estimated below for basic replacement of the KGEZ towers and transmitting equipment: 1) 5kW transmitter $42,000 2) Antenna Phasing system $24,000 3) 320 ft towers with lighting, installed $43,000 each 4) buried radial ground system with installation approx 58,000 ft of wire $23,000 5) control, lighting, RF and monitoring cables to match present layout $45,000 6) RF Monitoring and audio processing equipment $25,000 SITE SHARING It may be possible to relocate the KGEZ towers to share an existing tower site around the Kalispell area. This is known as diplexing. It will be necessary for the existing tower site to be within the allowable site areas shown in Exhibit E-6B. It will also be necessary to have enough land to accomodate the full ground system and the second tower as shown in Exhibit E-7. Tower heights need to be near the present 320 ft. to meet FCC minimum efficiency standards. Costs for diplexing equipment will vary widely with the height of the existing tower, the power of the existing broadcast station:, and the operating frequency of the existing station at the shared tower location. The diplexing equipment costs alone might well vary from $15,000 for the simplest low power station as the host to over $100,000 for a higher power multitower host station. VIR JAMES P.C. • BROADCAST ENGINEERING CONSULTANTS • 9c5 S. IRVING ST • DE,`JVER. GC =;D219 • PHONE 3L3) 93+-19CO --5- Although nonbroadcast towers might be theoretically useable for such shared use it is rare that nonbroadcast tower owners are interested in renting to an AM broadcast station. Costs of duplication of the KGEZ transmitting facilities would be similar to simple relocation with the exception of not requiring construction of one of the towers. OTHER COSTS For all options there will be local installation costs, -permitting costs, FCC filing fees, and required engineering reports for the FCC application to move and the FCC application for license after the new facility is constructed and proved out to meet FCC standards. I_c The present KGEZ transmitting plant is suitable forcontinued use for broadcasting but the existing towers are too tall to remain in use as is at the present location if the 'Kalispell airport is to be expanded. The presently available options are to change the KGEZ facility to Paran type towers, or to move the KGEZ facility to a new location either colocated with an existing tower or to a new location on its own. A more complete cost analysis will be necessary to closely estimate the total costs of moving KGEZ. Such analysis will require additional knowledge of the potential sites for such a move and if to a shared tower location knowledge of the specific use of the existing tower at the shared site. Respectfully submitted, D i, C Timothy C. Cutforth P.E. July 30, 1998 �IR JAMES P.C. • BROADCAST ENGINEERING CONSULTANTS • 965 S. IRVING ST • GENVE9. Co 5J2,9 - PHONE 937-"900 EXHEBiT E- 7 PLAT OF TOWER SITE PROPOSED KGEZ 500 kHz 5 kW-D I kW N DA 2 YALISP= MONTANA NLY 1998 ' � .JT •VJ lll.t 1. +! V1R J"KS P. C. TSYOTNY C. CUT/OR7H i.E, OtRECTOR OF iNO1NEEF"a BROADCAST ENGINEERING CONSULTANTS 965 S. IRVING ST. • SEWER, CO 80219 {303I 937-1900 • (800) 7794198