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/\ / \ / A \ / \ ===============/ \============== THE / R R \ LETTER VOLUME 4 \ / NUMBER 21 ===============\ /============== \ / \ L / \ / \/ October 10, 1985 The ARRL Letter is published bi-weekly by the Information Services Department of the American Radio Relay League, 225 Main St., Newington, CT, 06111; (203) 666-1541. Larry E. Price, W4RA, President; David Sumner, K1ZZ, Executive Vice President; Dave Newkirk, AK7M, Editor; Debra Chapor, Circulation Manager. Information from The ARRL Letter may be reproduced in whole or part in any form including photoreproduction and electronic databanks, providing credit is given to The ARRL Letter and to the American Radio Relay League. The ARRL Letter is available in printed form from ARRL. Subscriptions, limited to ARRL Members, are $19.50 (U.S. funds) per year for First-Class Mailing to the U.S., Canada, and Mexico. Overseas air mail subscriptions are available at $31 (U.S. funds) per year. Sample copies are available for an s.a.s.e. In this issue: o FCC PREPARES TO NAIL RADIO PIRATES o ARRL FILES COMMENTS ON PR 85-22 o ANOTHER HAM IN SPACE o ...and much more! ----------------------------------------- PERIMETER PROTECTION SYSTEMS ON 6 METERS? ----------------------------------------- In turning a Canadian company's petition for operation of a perimeter protection system into a Notice of Proposed Rulemaking, FCC appears to have deflected a potential threat to the Amateur Radio Service at 50-54 MHz. In the NPRM, General Docket 85-231, FCC responded to a request for a waiver of Part 15 at 50-88 MHz by proposing 54-88 MHz instead. It all began with a bit of alphabet soup called "CTLFDS" and ended up "GUIDAR." "CTLFDS" stands for "coupled transmission line field disturbance sensor." Control Data Canada, Ltd. (CDC), developed one and called it GUIDAR. It's a system that can be used to provide security surveillance for prisons, and to protect high-risk sites such as nuclear power stations from terrorism, theft and vandalism. GUIDAR operates on a principle of guided radar whereby a detection zone is created between "leaky" or ported coaxial cables deployed around the protected area. The present GUIDAR system employs two parallel cables buried approximately five feet apart and nine inches below the ground. An RF pulse is transmitted into one cable; some of this energy is coupled via the ports (holes) in the outer conductor of this cable into the ground and air near the cable. Some of this energy is reflected by objects in the ground and discontinuities in the soil, and is coupled into the second, or receiving, cable. When a human or other large object crosses between the cables, the change in RF coupled from cable to cable is detected and triggers an alarm. Such systems may cover a perimeter up to 2 miles long. On June 24, 1984, CDC asked FCC for a waiver of Part 15 of its rules to allow the operation of GUIDAR at 50-88 MHz. (Part 15 is that part of the FCC Rules governing operation of unlicensed low-power communication devices. Familiar Part 15 devices include cordless telephones, 49 MHz walkie-talkies, garage-door openers, etc. Such devices must not interfere with any other service; they must tolerate interference from other services.) Why did CDC make a run at 50-88 MHz? The aim was improved performance of its GUIDAR. CDC indicated that the ability of the system to detect actual intrusions and to ignore objects that could cause false alarms is affected by the frequency of operation. Below 30 MHz, sensitivity of the system to humans drops dramatically. Operation above 100 MHz increases the system's sensitivity to small animals, resulting in numerous false alarms; also, above 100 MHz, signal loss in the cable is significant. CDC stated that such systems must operate somewhere between 30 and 100 MHz. CDC stated that the present rules in Part 15, Subpart F, allowing perimeter protection systems to operate in the range 40.66 to 40.70 MHz, do not allow for effective operation of a system such as GUIDAR. GUIDAR uses a pulsed signal with a bandwidth of 2.5 MHz. A pulsed signal is employed to allow determination of the exact location along a perimeter where intrusion has occurred. CDC proposed 50-88 MHz for GUIDAR. This range includes the amateur 6-meter band, TV channels 2-6 and radio astronomy and avigation at 72-76 MHz. CDC contends that its perimeter protection systems can operate in the 50-88 MHz range without causing interference to radio services on those frequencies. In the NPRM, FCC said that CDC's reasons for selecting 50-88 MHz, rather than 30-50 or 88-100 MHz, were "unclear." Yet, "In view of the public benefits to be derived from improved security at facilities such as prisons and nuclear plants, we find it appropriate to accommodate such systems to the extent possible." Operation of CTLFDS on vacant VHF TV channels sits well with the Commission. But what about 6 meters? Said FCC, "We have reservations about also permitting these systems to operate in the 50-54 MHz am because these systems could extend for considerable distance around a large facility, thereby increasing the likelihood that an amateur transmitter could come in close proximity to some part of the system." What has been proposed by the Commission is a set of standards for perimeter protection systems allowing for operating at 40.68 MHz, 54-72 MHz and 76-88 MHz. For systems operating between 54 and 88 MHz, strength of emissions is not to exceed 10 microvolts per meter at a distance of 30 meters -- the same limitation placed on computers for use in residential areas. FCC carved 50-54 MHz and 72-76 MHz from CDC's original proposal: "Permitting operation on TV channels 2 through 6 should be more than sufficient, since this ensures that in any given area there will be at least two vacant TV channels on which a perimeter protection system could be set to operate." Comments on General Docket 85-231 were due by October 11, 1985, with the League to file in support of FCC's decision to keep these devices out of the 6-meter band. Reply Comments are due on or before November 12. ---------------------------------- FCC PREPARES TO NAIL RADIO PIRATES ---------------------------------- The Federal Communications Comission's monitoring network is continuing to investigate and fine illegal radio operators on a number of frequencies. Through long-distance direction finding, unlicensed "pirate" radio operations have been identified near these cities: Richmond, Charlottesville and Staunton, VA; Youngstown, OH; Miami and Orlando, FL; Minneapolis, MN; Washington, DC; Louisville, KY; Waterbury, CT; Newark, DE; Grand Rapids and Lansing, MI; San Francisco, CA; Arkansas City, KS, and Fort Smith, AR. The operation of unlicensed radio stations is in direct violation of FCC Rules and Regulations. Their operation may endanger life and property by causing harmful interference to licensed radio operations. One such pirate station, "KRZY" of Arkansas, was located and inspected on March 9, 1985. As a result of the inspection, a $1000 Notice of Apparent Liability was issued for unlicensed and out-of-band operation. The same operator soon returned to the air, and on August 9, 1985, U.S. Marshals, accompanied by an agent from the FCC District Office in Dallas, served a warrant and seized transmitting equipment used by the radio operator. The search and seizure resulted from a close-in DF to his residence on August 16, 1985, at which time the station was identifying itself as "KBBR" on 7440 kHz. If convincted of operating an unlicensed radio station, the operator faces a maximum penalty of one year imprisonment, a fine up to $10,000 and a possible forfeiture of radio equipment to the U.S. government. Persons having information that would assist the FCC in its effort to locate and close down pirate radio stations should contact: Engineer in Charge, FCC, P.O. Box 1588, Grand Island, NE 68802-1588; telephone (308) 382-4296. --------------------------------- NEW ADDRESSES FOR TWO FCC OFFICES --------------------------------- FCC's Anchorage District Office has moved to 6721 West Raspberry Road, Anchorage, AK 99502, telephone (907) 243-2153. The Honolulu Office has moved shop as well; their address is Waipio Access Road, Next to the Ted Makalena Golf Course, P.O. Box 1030, Waipahu, HI 96797. The telephone there is (808) 677-3318. Both offices are open from 8 A.M. to 4:30 P.M. Public inquiries concerning telecommunications matters, complaints of electronic interference and schedules of commercial radio operator examinations should be directed to these addresses. ----------------------------------- THAT THIRTY-DAY RULE ISN'T GONE YET ----------------------------------- From the ARRL/VEC office comes this reminder for all ARRL- accredited Volunteer examiners: don't forget that the thirty-day wait rule remains in force until November 8. Don't risk your license by breaking the rule while it is still on the books. After November 8, each VEC entity may set its own waiting period. Once the ARRL Board has determined the cost impact of this rules change, ARRL/VEC VEs will be advised as to what the ARRL/VEC retest policy will be. ----------------------- COHERENT CW ON LONGWAVE ----------------------- Have you heard of the 1750-meter band? It spans 160-190 kHz, and U.S. experimenters there are allowed unlicensed operation with no more than 1 watt DC input and a 15-meter antenna. (Don't get out your calculators; that's like having QSOs on 80 meters with a wire just a hair longer than two feet!) It is possible to make electromagnetic hay on 1750, though -- especially if you jump into the experimental spirit of the band and its users. More and more 1750-meter experimenters, or LOWfers, as they're nicknamed, are turning to uncommon technologies in their quest to span greater distances on the band. One such technology is coherent CW (CCW). What's coherent CW? There's quite a bit on the technique on pages 21-9 to 21-12 of the The ARRL 1985 Handbook for the Radio Amateur. Simplistically put, it's a method wherein transmit and receive frequencies, keying speed, and receiver bandwidth are synchronized, allowing something like a 20dB improvement in signal-to-noise ratio at 12 WPM over non-coherent CW systems at similar signalling rates. From the September issue of QEX, the ARRL Experimenter's Exchange, comes this report on 160-190 kHz CCW: "Mike Mideke, WB6EER, and I have been experimenting with coherent CW in the 1750-meter experimental band. My CCW beacon is located in Morro Bay, California, transmitting 10-baud CCW, while Mike is receiving with a Petit PCF-3 coherent CW filter (QST, May 1981). A digital dot is precisely 0.1 second, while dashes, space and blanks between elements are 0.3 second long. A 32-bit memory is used, making the entire ID 10.7 seconds. All experiments have been conducted on 176 kHz, as sufficient RF stability occurs with ordinary crystal control. 166.66667 kHz was planned, but carrier accuracy is far less stringent than first thought! "Phase-locking to 10-MHz WWV was discarded after the discovery that 100-kHz LORAN C signals were received while tranmitting on the same antenna, using a simple 100-kHz tuned circuit. A basic 100-kHz receiver is now needed with only a sample and hold output such that a phase lock can be achieved with a 1-MHz crystal. A commercial LORAN C unit was used for this initial try. "It is becoming more apparent that stabilities and complexities first thought necessary are not required when the communication experiment lasts for a few hours, or can be optimized by the operator on the spot. Both Mike and I are now look-ing for an experimenter in, say, the Hawaiian islands, to show what coherent CW and one watt of power can really do" -- Cliff Buttschardt, W6HDO, 950 Pacific St., Morro Bay CA 93442.