RF CURRENT



Welcome to RF Current, a weekly electronic newsletter focusing on Broadcast technical and F.C.C. related issues. This newsletter is part of The RF Page @ www.transmitter.com, a web site devoted to TV Broadcast RF engineering. For more information see the What is... guide to the R.F. Page site.

This page contains stories from RF Current issues published in November 1998. Links referenced in the articles were current when published but by this time may have changed. If you find a bad link, try connecting to the home page of the publication or company and look for an archive of past articles. If you find a changed link, I'd appreciate it if you'd let me know by dropping me a note indicating the new location at dlung@transmitter.com.

NOTICE:

RF Current was not published November 30. The December 7 issue includes stories released after November 25.

November 25, 1998 - Issue 143 Delayed Edition

FCC Affirms Decision to Make More Spectrum Available for Mobile Sat Service (Nov. 24)
The Commission affirmed its 1997 decision allocating 70 megahertz of spectrum at 1990-2025 MHz for Mobile Satellite Service (MSS) uplinks and 2165-2200 MHz for MSS downlinks. In addition, the Budget Act of 1997 directed the FCC to allocate 2095-2110 MHz for assignment by auction. These two actions will result in the loss of 35 MHz of the the TV Broadcast Auxiliary Service (BAS) at 2 GHz. The FCC also adopted Third NPRM proposals for additional spectrum, relocation, and transition mechanisms.

The FCC sought comment on "various transition mechanisms for the replacement or retuning of BAS equipment to faclitate expeditious access to the spectrum by MSS and on the appropriate apportionment of replacement or retuning costs among MSS licensees." FCC Chairman Kennard said the decision to extend the FCC's Emerging Technologies policy for FS microwave licenses to Broadcast Auxiliary licenses was a wise one. He commented, "The BAS is essential for providing coverage of breaking news, sports events, and other special events to the American public, and many of the incumbent Fixed Service microwave licensees provide critical infrastructure and public safety services."

More information in available in the FCC Office of Engineering and Technology News Release (nret8017) released November 19 and the Notice of Proposed Rulemaking (fcc98309) released November 24..

FCC Proposes Non-Geostationary Satellites Services in the Ku-Band and Considers Expanded DBS Services (Nov. 24)
The FCC is proposing to allow non-geostationary orbit (NGSO) fixed satellite services (FSS) to operate on a co-primary basis in Ku spectrum. Satellite downlink operations would be permitted 10.7-12.7 GHz and uplinks in the 12.75-13.25 GHz and 13.8-14.5 GHz bands. The 13.75-13.8 GHz and 17.3-17.8 GHz bands were excluded "due to interference concerns with incumbent operations." In the Notice of Proposed Rulemaking, the FCC also sought comments on a request to "permit the terrestrial retransmission of local television signals and the provision of data services to DBS service subscribers operating in the 12.2-12.7 GHz band."

The FCC recognized that this spectrum has "considerable incumbent use" in the U.S., including use by the broadcast satellite service, broadcast auxiliary microwave, geostationary FSS, and various commercial and goverment terrestrial fixed operations. The Notice requested comments on appropriate sharing criteria and emphasized that "new NGSO operations should not be permitted to hinder the future evolution of incumbent services or their ability to implement new and innovative technologies." However, the FCC Notice also pointed out that "WRC-97 provisionally adopted NGSO spectrum sharing criteria that will likely be implemented globally unless alternative proposals, with sufficient technical proof and justifications, are received."

More information in available in the FCC Office of Engineering and Technology News Release (nret8017) released November 19 and the Notice of Proposed Rulemaking (fcc98310) released November 24..

INDUSTRY - Sinclair Broadcast Invests In Acrodyne - Ostroff returns as Acrodyne Chairman (Nov. 23)
Over a decade ago Nat Ostroff left Acrodyne, a company he helped create, to join Comark Communications as President. Later, Ostroff left Comark to become Sinclair Broadcast Group's Vice President of New Technology. Under a deal announced this week, Ostroff will be returning to Acrodyne.

Sinclair has agreed to make a cash infusion of 4.3 million dollars in Acrodyne in consideration for shares of common stock and warrants to purchase additional shares. At the close of the transaction, Acrodyne's Board of Directors will be reconstructed to include three directors nominated by Sinclair, with Nat Ostroff as Chairman, two directors nominated by Acrodyne's President and CEO Robert Mancuso and two independent directors not affiliated with Sinclair or Acrodyne.

This transaction is subject to the approval of Acrodyne's stockholders and other conditions. More details on the transaction, including the financial arrangements, is available in the Acrodyne Press Release.

SATELLITE - More Problems for PanAmSat - Battery Cell Failures Affect Two Satellites (Nov. 23)
An article in the Wall Street Journal Thursday, November 19, reported that General Motors' last 10-Q quarterly filing indicated PanAmSat was experiencing more problems with its Hughes-built satellites.

In the General Motors Form 10-Q filed November 16th, GM described the failures in the primary spacecraft control processor on four PanAmSat satellites, including the loss of the Galaxy IV satellite. As reported earlier, Hughes said the "the failure of the second SCP on Galaxy IV appears to be unrelated and is being treated as an isolated anomaly."

On page 42 of the most recent 10-Q (see link above), GM says "Battery anomalies have occurred on two other Hughes-built PanAmSat satellites. In both cases, battery cells have failed resulting in the need to shut-off a number of transponders for a brief time during twice-yearly eclipse periods." The filing notes that while the implate on customers has been minimal, "There can be no assurance, however, that service to all full-time customers will not be interrupted for brief periods during future eclipse periods or that additional battery cell failures will not occur in the future. Such future service interruptions, depending on their extent, could result in a claim by affected customers for termination of their transponder agreements."

The filing said "PanAmSat is developing solutions for its customers that may include transition of certain services to other PanAmSat satellite or the launch of replacement satellites." The SEC filing did not list which satellites had the problem battery cells. The PanAmSat web site did not have any information on the battery anomalies.

DTV - Lucent Digital Video Announces Closed Captioning Solution for DTV (Nov. 18)
Lucent Digital Video, ULTECH Corporation, WCVB-TV/Boston, and the WGBH Educational Foundation announced they had created the first working on-air closed captioning solution for DTV. Lucent Digital Video designed an open interface between any closed captioning generator and its FlexiCoder™ MPEG-2 encoder, sold by Harris Corporation. In a demonstration at WCVB, captions from WGBH's The Caption Center were inserted on WCVB's DTV signal using ULTECH Corporation's DTV-708 Closed Caption Data Server.

More information on the closed captioning process, quotes from the participants in the demonstration and other information is available in the Lucent Press Release.

FCC Begins Rulemaking on Definition of TV Grade B Signal Intensity (Nov. 17)
Ask most TV engineers what defines a UHF TV station's Grade B contour and you will hear a precise definition such as "the contour defined by the 64 dBu/m field intensity contour as defined using the FCC 50/50 curves in Part 73 of the FCC Rules." The signal level is lower for VHF stations - 56 dBu for channels 7-13 and 47 dBu for channels 2-6. This definition, however, may not be the one the FCC wants to use when defining coverage for purposes of the 1988 Satellite Home Viewer Act.

FCC News Release (Report CS 98-16) said:
"In order to better identify those consumers who can and cannot get their local broadcast television stations over the air, the Commission has adopted a notice of proposed rulemaking (FCC 98-302) seeking comment on the way it defines, measures, and predicts the strength of television signals. Television signal intensity is the key element in determining whether a consumer is "unserved" by broadcast network stations and, thus, is eligible to receive those stations using a home satellite dish under the 1988 Satellite Home Viewer Act (SHVA)."
The FCC News Release also stated:
"The notice of proposed rulemaking seeks comment on the extent of the Commission's authority to amend its Grade B definition only for purposes of the SHVA. The notice also asks for comment on how the definition of signal of Grade B intensity could be redefined and how better to measure the signal intensity at a particular household. In addition, the notice invites proposals for methods to predict which households are likely to receive a Grade B signal."
Echostar requested signal level be calculated using a model that "predicts an area where 99 percent of households receive a Grade B signal 99 percent of the time with a 99 percent confidence level." NRTC, a distributor of the DirecTV DBS service, requested defining the area as one where 100 percent of the population receives a Grade B signal 100 percent of the time. There is also concern that factors such as buildings and vegetation can affect signal levels and these are not reflected in the FCC's definition of Grade B.

While the FCC would consider adopting another model, such as Longley-Rice, for determining coverage, these predictive models would not preclude the use of actual coverage data. Please refer to the full text of the Notice of Proposed Rulemaking (FCC 98-302) for a more thorough discussion of both the technical and legal aspects of this Rulemaking.

FCC Releases Digital Television Consumer Bulletin (Nov. 17)
Yesterday the FCC's Office of Engineering and Technology issued a Digital Television (DTV) Consumer Information Bulletin to provide consumers information on the deployment of DTV, the capabilities and features expected to be available in new DTV sets, and cable/broadcast equipment compatibility. The Bulletin answers questions including "Why change today's TV system to DTV?", "What is DTV?", "Do I need a new TV set to receive DTV?", "Do I need a new TV set to receive DTV?" and others on TV set cost, outdoor antennas, and cable programming.

For more information see the FCC's News Release (Report ET 98-10) and Digital Television Consumer Information.

OTHER Items of Interest

November 16, 1998 - Issue 142 Final Edition

SATELLITE - Leonids Meteor Shower Update (Nov. 16)
Within 48 hours we will know how many satellites, if any, fell prey to the onslaught of meteors from what is expected to be the greatest Leonids meteor shower since 1966. Analytical Graphics, in an a report on the Nov. 17-18 Leonids Meteor Shower, said calculations showed "we might expect 5 to 10 functional satellites to be hit by Leonid meteoroids during a storm (assuming an average spacecraft area of 20 m2."

GE Americom said it will provide regular status reports during the peak of the storm Tuesday afternoon (EST) on its web site. NASA has collected an extensive list of Leonids Links. Sky and Telescope has a page listing articles on Leonids and other meteor showers. Images of the meteor shower will be available tonight and tomorrow night at http://www.leonidslive.com/. See the October 5, 1998 RF Current for additional links and information.

DTV - Panasonic Announces Availability of All-Format DTV Tuner/Decoder Card (Nov. 11)
November 9th Panasonic Industrial Company announced the availability of "the computer industry's first" all-format DTV tuner/decoder card. Developed in collaboration with Compaq Computer, the card consists of a tuner board to receive both ATSC 8VSB signals and NTSC analog signals and a video decoder board capable of decoding all 18 ATSC formats (plus NTSC) for display.

Panasonic said samples of the DTV-PC card will be available by the end of this year, with volume production in early 1999. Pansonic also announced immediate availability of its Model TTM1A 8VSB transport stream (TS) output board. The board "outputs an 8-bit parallel transport stream from the RF input of broadcast DTV signals. More information is available in the Panasonic Press Releases Panasonic Launches World's First HDTV Solution for Personal Computers - PC-DTV Card Is Fully Compatible With All ATSC Formats + NTSC and Panasonic and Compaq Co-Develop World's First High Definition Digital Television Tuner-Decoder for Personal Computers.

FCC Releases New Form For DTV License Applications (Nov. 11)
Now that it has been approved by the Office of Management and Budget, the FCC encourages DTV permittees to use the new Form 302-DTV, dated August 1998. The FCC Public Notice (pnmm8160) said "Since some applicants may have nearly completed the old license application form, the Commission will continue to accept DTV license applications prepared on FCC Form 302-TV until December 31, 1998. However, applicants are encouraged to use the new form as it is a much simpler form to complete."

The form is available from the FCC Form Page as Adobe Acrobat PDF file 302-dtv.pdf.

DIGITAL TELEVISION STATION ACTIONS/GRANTS - See ac981112.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KBHK 45 UTV of San Francisco San Francisco CA 206.3 446


OTHER Items of Interest

November 9, 1998 - Issue 141 Final Edition

FCC Declines Major Changes to Family Radio Service in Memorandum Opinion and Order (Nov. 9)
The FCC declined to make most of the changes to the Family Radio Service (FRS) rules requested by the Personal Radio Steering Group (PSRG) and Michael C. Tranos. The FCC clarified that "GMRS and FRS units operating on the same frequencies may communicate with each other if the individual operators so choose." As requested by Motorola, the FCC agreed that FRS units that allow the antenna to be easily detached could be used with external power amplifiers or an external antenna, which would defeat the purpose of Section 95.194(c) of the FRS rules. Consequently, the FCC stated "consumer attached devices such as these are not type accepted with the FRS unit, and, therefore, can not be used with it." Refer to the full text of the Memorandum Opinion and Order (FCC98-293) for more information.

FCC - USA Digital Radio Partners Petitions for AM-FM In-band Digital Audio Broadcast Service
USA Digital Radio Partners L.P. (USADR) filed a petition for rulemaking to amend Part 73 of the FCC Rules to permit the introduction of digital audio broadcasting (DAB) in the AM and FM bands. The petition proposes adoption of an in-band on-channel (IBOC) DAB technology that the petitioner contents would enable simultaneous broadcast of analog and digital signals.

USADR requested the Commission:

Statements opposing or supporting the Petition for Rulemaking may be filed until December 23, 1998. Reply comments are due by January 23, 1999. The FCC Public Notice (da982244) annnouncing the Petition for Rulemaking stated an Adobe Acrobat version of the filing was available at http://www.fcc.gov/Bureaus/Mass_Media/Filings/rm9395.pdf, however, as of November 9, that link was not valid.

TECHNOLOGY - Harris and NRL Design First Combined Ku-band/Ka-band Mobile Satellite Uplink (Nov. 3)
Harris Corporation has designed a dual Ku-band/Ka-band for the Naval Research Laboratory (NRL). The modified Harris S-26 SNG truck will be used by NRL for demonstrations, testing and evaluation. The Ka-band portion of the uplink posed several engineering problems. The system had to be able to deal with the signal distortions and losses present at these frequencies while maintaining precision tracking in spite of environmental changes. COMSAT/RSI worked with Harris designing the antenna system - a modified version of COMSAT/RSI's 240 KVO antenna. Other equipment includes CPI Ku-band TWT amplifiers, Logimetrics Ka-band TWT amplifiers and Miteq Ka-band up/downconverters. The mobile uplink is built on an International 4700 chassis.

Pat Piper, satellite systems product manager for Harris Corporation's Broadcast Systems Division commented that "Although this satellite uplink system will be for military use, the technology has great potential in broadcast applications. Currently the high-frequency Ka-Band is primarily for military use, but its next logical step is for program distribution of high definition television (HDTV) signals with their large bandwidth requirements." This information was obtained from a Harris Press Release.

DTV - CEMA 10th Annual Digital Engineering Conference Set for New Jersey Venue (Nov. 3)
Yesterday CEMA announced the 10th annual Digital Engineering COnference - the Consumer Electronics Future, will be head March 23-24, 1999 at the Crown Plaza Hotel in Hasbrouck Heights N.J. The conference is geared towards engineers, engineering management and product development managers. Topics covered in the conference include the IEEE-1394 interface, copy protection, the Open Cable initiatives, ATSC PSIP, digital recording and multichannel audio.

More information on the conference and the programs is available in the CEMA Press Release.

DIGITAL TELEVISION STATION APPLICATIONS - See ap981104.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KPST 34 Golden Link TV Vallejo CA 200 419 Dielectric TUP-C3-8-1
KRMA 18 Rocky Mtn Public TV Denver CO 1000 435 Dielectric TFU-24GBH-R08


DIGITAL TELEVISION STATION ACTIONS/GRANTS - See ac981109.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KNSD 40 Station Venture Operations San Diego CA 18.2 566 Dielectric TFU-10DSCS180
KCPT 18 Public Televsion 19 Kansas City MO 48 355 Dielectric TFU-30J
WSOC 34 WSOC Television Charlotte NC 370 352 Dielectric TUP-04-12-1


OTHER Items of Interest

November 2, 1998 - Issue 140 Final Edition

DTV - ATSC Releases Report on the "Top-Down" Meetings on DTV Implementation (Oct. 30)
Broadcast engineers and facilities designers now have a new tool to help them design and build DTV stations. The Advanced Television Systems Committee Implementation Subcommittee Report on Findings of the Top Down Meetings, released October 30, provides a generalized blueprint for a DTV station from the output of the production facilty through the transmission of the DTV signal. While it is unlikely any station would want to follow the Report's blueprints exactly, they can use portions of the blueprint to meet their current needs. The Introduction to the Report said:
"By establishing a single system map where all of the likely system elements and interfaces could exist, a commonality in design and functionality throughout the industry is established which does not only point the way for the early DTV adopters but also establishes a framework upon which to build and expand systems in the future. Setting the direction of expansion is important for station and manufacturer alike in order to have a cohesive, cost-effective, and orderly transition to DTV."
The introduction also notes "This inventory was intended to serve as a guide of sorts to point to the standards that exist for equipment interfaces, identify potential conflicts between those standards, and identify areas where standards and/or technology need further development."

Topics covered in the report include Video Routing and Formats, Encoding and Multiplexing, Station In/Out, Data Services, Redistribution Signals, Audio, Control, Timing, Monitoring and a Description of Functional Blocks. The document is available in Microsoft Word and Excel formats from the ATSC web site. See http://www.atsc.org/Cover_Top-Down.html.

DTV - RCA Announces HDTV Sets and $700 DTV Set-top Converter Box (Oct. 28)
Thomson Consumer Electronics has set a new price point for HDTV set-top converter boxes and introduced a range of products to make it easier for consumers to see digital TV. The RCA DTC100 set-top converter can connect to current analog TV sets and receive all ATSC broadcast formats as well as DirecTV and USSB digital satellite programming. The suggested retail price for the DTC100 is $699. It will be demonstrated starting in November and will be available "early next year".

Viewers that want an HDTV display will be able to purchase the RCA P55000 (suggested retail price $6,999) 55 inch (diagonal) TV or the PROSCAN PS61000 (suggested retail price $7,999). Unlike some of the earlier HDTV introductions, these rear-projection sets include a DTV tuner capable of receiving ATSC over the air and DirecTV and USSB digital satellite broadcasts. These HDTV sets process digital picture resolutions up to and including 1920x1080 interlaced. Other ATSC HDTV formats are automatically converted to 1080i. SDTV and NTSC images are up-converted to 540 line progressive display.

Thomson recognized viewers will need antennas to receive the first HDTV broadcasts. Two RCA dish antennas are being offered - a remote controlled rotating amplified dish antenna, the model ANT2500X (suggested retail price $299.95} and an omnidirectional antenna, the model ANT2020X (suggested retail price $179.95). For more difficult receiving locations, Thomson has the ANT40U, a 60 inch long, "37 element UHF analog antenna optimized to receive HDTV signals, as well as locally broadcast UHF analog programming."

Thomson issued an extensive series of press releases describing their HDTV product line. Refer to them for more information.

DTV - Argentina Picks ATSC DTV Standard (Oct. 28)
In a resolution dated October 22, Dr. German Kammerath, the Secretary of Communications of the Republic of Argentina, announced Argentina had officially adopted the ATSC DTV standard for digital terrestrial broadcast. Although Argentina also evaluated the DVB-T standard, the ATSC system had several advantages that led to its adoption. Among the advantages cited, the order listed better transmission coverage, invulnerability to impulse noise, a higher bit rate and higher quality of the Dolby AC-3 multichannel audio system. The order also noted that receivers capable of commercialization in the international market already exist for the ATSC Standard, while DVB receiver are currently limited to channel bandwidths of 7 or 8 MHz instead of the 6 MHz bandwidth used in the Americas and parts of Asia.

More information on Argentina's decision is available in the ATSC Release - Argentina First in South America to Adopt a Digital Television Standard, Choosing ATSC.

DTV - Harris and Lucent Announce Tests to Ensure HDTV Sets Accept DTV Signals from Harris FlexiCoder™ DTV Encoding System (Oct. 28)
Harris Corporation and Lucent Digital Video announced they had completed "the broadcast industry's first tests to ensure that new high definition (HDTV) receivers accept over-the-air signals generated by a leading digital television (DTV) encoding systems, the Harris FlexiCoder™." The tests showed HDTV receivers from Mitsubishi, Panasonic, Philips, Samsung, Sharp, Thomson, and Zenith passed the interoperability tests. Other receivers are under testing now or are scheduled for future testing.

More information on the tests and the Harris FlexiCoder is available the Lucent Press Release and the Harris press release.

TECHNOLOGY - New Car Antennas May Cool Interior, Defrost Windows, Receive Radio... (Oct. 28)
Engineers have found a way to use common car window components as antennas for receiving AM and FM broadcasts. The researchers at Ohio State University designed an antenna using transparent metal film imbedded between the layers window glass. This film deflects heat from sunlight, keeping the car interior cooler. Eric K. Walton, senior research scientist and adjunct professor of electrical engineering, and his students have received patents on this antennas as well as one based on the heating wires used in rear window defrosters.

Walton's team designed the coupling techniques required to connect the radio to these antennas. No details were given on the method for coupling the signal from the metal window film, although there was a note about the coupling circuit for the window heater wires. The Ohio State News Release said "Walton and his students built an isolation transformer system that allows AM/FM reception while permitting heating power to pass through."

How does it work? According to the news release, for AM reception, an early design of the film antenna was 5 dB better than a traditional antenna. For FM stations, the received signal was 5 dB weaker, although this has now been improved. Information on the first design was reports in a recent issue of the IEEE Transactions on Vehicular Technology. The researchers are working with sponsr PPG Industries to combine the two technologies into a heated metal film. Walton said "If we put both these patents together, we could produce a front windshield that can help cool a car in summer, defrost itself in winter, and receive AM/FM signals -- but still remain completely transparent."

FCC Grants GE Americom GE-5 Modification (Oct. 28)
The FCC granted a request by GE Americom to substitute a Ku-band only satellite for the hybrid satellite authorized for GE-5. GE Americom asked for this modification to permit expedited introduction of Ku-band service at 79 degrees. GE Americom's also filed a related application to launch and operate a separate C-band spacecraft at GE-5's 79 degree West Longitude orbit location. The FCC declined to rule on that application in this order. Details are available in FCC Memorandum Opinion and Order DA98-1029.

SATELLITE - GOES-8 Weather Satellite Experiences Large Attitude Disturbance (Oct. 27)
At 0740 UTC Sunday morning the GOES-8 weather satellite was placed in a safe mode due to a large attitude disturbance. After meeting with engineering representives from NOAA, NASA and Space Systems/Loral and a series of tests on the Earth sensor and attitude control, GOES-8 was commanded back to normal on-orbit mode at 2300 UTC Sunday night, October 27, with the redundant Earth sensor in control. During the time the satellite was in the safe mode images were not available from GOES-8. Image navigation performance was severely degraded during the 24 hours after the GOES-8 recovery.

Information on the status of the GOES spacecraft is available from the NOAA/NESDIS Office of Satellite Operations Home Page.

FCC Commissioner Ness: Technical challenges are not nearly as daunting as the advent of DTV itself (Oct 27)
Speaking about the transition to DTV at the MSTV Annual Update in Washington, D.C., FCC Commissioner Susan Ness said "There will be bumps along the way." "Of course not everything will flow smoothly. But the technical challeges are not nearly as daunting as the advent of digital television itself."

Some of the "bumps" Ness listed include compatibility among different digital users, copy protection, multipath problems, and "even the size of the new sets." She said the Commissioners " are just about to finish the Second Reconsideration of the 5th and 6th Report and Order, which includes, among other things, a decision on whether and when to allow broadcasters to maximize power above 200 kW." Other decisions needed soon include a decision on whether the Commission should assign "transport identification numbers" to facilitate use of the voluntary PSIP standard. Ness also warned broadcasters not to " ignore programming and interactive opportunities that take full advantage of the extraordinary potential of digital television."

DIGITAL TELEVISION STATION APPLICATIONS - See ap981027.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
KTLA 31 KTLA Los Angeles CA 310 (mod.)


DIGITAL TELEVISION STATION ACTIONS - See ac981102.txt for more information
Call (DT) Ch. Licensee Location ERP (kW) HAAT (m) Antenna
WAGA 27 WAGA License Atlanta GA 964 332
WRTV 25 McGraw-Hill B'cstg Indianapolis IN 898 294 Dielectric TFU-30GTH-R04
KDKA 25 CBS Pittsburgh PA 727 311 TFU-24GTH-R04


OTHER Items of Interest

Other Issues Available:

1998

1997

1995 and 1996

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Last modified November 26, 1998 by Doug Lung dlung@transmitter.com
Copyright 1998 H. Douglas Lung