Amateur Television Station W5YF
at Southern Methodist University
by Robert Monaghan W5VC

Scenes from North Texas AB5IG Amateur Television Repeater

ATV Repeater AB5IG Four Panel Display
Local North Texas Weather Radar Imagery
Images courtesy of AB5IG ATV Image Grabs Pages

November 1999 W5YF Club Meeting (draft page)
Topic: Amateur Television in North Texas with Lee Rhoden AB5IG
    Lee Rhoden AB5IG's talk reviewed:
  • history of Amateur Television in North Texas
  • AB5IG ATV Repeater Facilities in downtown Dallas
  • future High Definition Television (HDTV) plans
  • video resources available thru AB5IG (Skywarn Radar, NASA TV..)
  • past ATV programs such as White Rock Marathon, Dallas Air Show, Ham-Com..

Related Links:
AB5IG Amateur Television Repeater Pages
North Texas ATV Image Grabs
ATV Links Pages

Updates

Demo ATV station Setup (photos of AB5IG ATV repeater antenna and station demo)
ATV Station W5YF Updates Through July 2004
ATV 1.2 ghz/440 Mhz stations funded!
ATV on Events 2004 Updates Pages

In 1999, we revised our amateur radio club's name to include the word "Telecommunications". We did so because our hobby now includes much more than just radio. Nothing highlights our expanded capabilities more than our new expansion into Amateur Television (ATV) activities.

ATV Operations Setup Party - Oct. 30, 1999

Since Saturday, October 30th (1999) was a dreary, rainy and cold day, I really didn't expect anyone to show up for our ATV project day. But I was wrong. I hadn't reckoned on the enthusiasm of local ATVers such as Rik Albury (K4TTT) and Mont O'Leary (K0YCN) to help get S.M.U. on the air. Mr. Albury is a former instructor at S.M.U., while Mr. O'Leary is one of the Dallas Amateur Radio Club's advisors on our club's Leadership Council. Both are active and avid ATVers, with a sincere interest in helping promote Amateur Television to a broader audience in the North Texas area. Club members Robert Monaghan (W5VC), Bill Hughes (club treasurer), and Aamer Mahmood also helped and observed. Other local ATVers including Willis (at W5YF) also helped confirm station operations, as well as providing interesting demonstrations of their own amateur television stations.

Steps to Bringing Up an Amateur Television Station

The first step in creating an ATV station is a receiving antenna. Fortunately for us, we have a direct line of sight to the AB5IG Amateur Television repeater. An ATV repeater receives signals from local users, then amplifies and retransmits (or repeats) them on another output frequency. Repeater location is critical, since a tall antenna location can provide line of sight coverage extending over 60+ miles to fully cover the North Texas area if centered in downtown Dallas near SMU. The AB5IG ATV repeater is located on top of the tall NationsBank building in downtown Dallas whose sides are lined with greenish fluorescent lights, earning it the name "Green Weenie".

Basic Elements of S.M.U.'s W5YF Amateur Television Station Receiving Setup (Images from AB5IG ATV Gear Pages)

ATV Grid Receiving Antenna
Receives AB5IG ATV Repeater on 2.4 Gigahertz
ATV Low Noise Block Downconverter
Converts 2.4 Ghz to regular TV channel frequencies
AB5IG ATV Repeater
shown on $99 Commercial TV Receiver

Due to the low clouds and intermittent rain, we couldn't see downtown Dallas at first, so we aimed the receiving antenna by memory. The ATV receiving antenna was attached to the base of our former satellite antenna (soon to be resurrected, we hope!). A low noise block amplifier and downconverter ("LNB") is connected to the antenna. Power for the LNB is fed up the 75 ohm coax from the W5YF station, while the block of ATV channels is fed down the same coax to the television receiver. A conventional home television receiver such as you might have in your dorm apartment or home is used. The AB5IG amateur television repeater is received on the television receiver on local channels 10 and 12.

The second step involves setting up an ATV transmitter. For this, you need a TV camera and transmitter, low loss coaxial cable to a roof top directional antenna, and a microphone. The TV camera can be a simple chip camera with NTSC video (color preferred) costing as little as $50. The coaxial cable has to be of a special type with low loss at these microwave frequencies. Even so, a typical cable will lose 5 decibels of signal strength every hundred feet. Fortunately for us, the club's direct roof access cable port is only a fifty foot cable run to our ATV transmitting antenna site. This handy location not only cuts the cost of cabling (at $1 a foot) but also cuts the amount of signal lost in the cable wiring to the antenna.

Basic Elements of S.M.U.'s W5YF Amateur Television Station Transmitting Setup (Images from AB5IG ATV Gear Pages)

22 element yagi ATV Antenna on 1.2 Gigahertz
Vertically Polarized 16 dB Gain
Driven element of 1.2 Ghz ATV Antenna closeup
ATV 2 Watt Transmitter for 1.2 Ghz
Houston ATV Society (HATS) Design

The high gain antenna uses a series of reflecting and directing elements to provide a high degree of gain at minimal cost (e.g., circa $90-100). Mounted directly above the receiving antenna and LNB, the transmitting antenna is rather directional, meaning it must be carefully aimed at the ATV repeater site. Fortunately for Rik Albury and I, the rainy clouds lifted a bit late Saturday afternoon, enabling us to confirm our aim at the "Green Weenie" ATV repeater site atop NationsBank building in downtown Dallas.

Surprises for an ATV Neophyte

Probably the most astonishing thing to me about the entire Amateur Television station is the incredibly low power of these microwave ATV transmitters. The standard ATV transmitter used locally has an output power of only 35 milliwatts. So thirty or so ATV transmitters would have a combined output power of around one watt! Put another way, turning a 100 watt light bulb on for one second is equivalent to roughly an hour's worth of Amateur Television transmitter power. More remote stations may increase their microwave ATV transmitter power to 2 watts. The 35 milliwatt power level also works directly with a "high power" 18 watt microwave amplifier. I have to put "high power" in quotes, since for most radio amateurs 2,000 watts is high power, not 2 or 18 watts. Yet most of the local commercial television stations use tens and even hundreds of thousands of watts per hour in their television transmitters for similar quality local coverage. In short, the Amateur Television microwave frequencies offer a lot of advantages over conventional commercial TV.

Please Don't Cook that Turkey Now, I'm on ATV!

There is one minor disadvantage with using ATV microwave frequencies. Similar frequencies are used by microwave ovens to cook everything from turkeys to heating coffee and tea. So a badly shielded microwave oven can put out enough noise locally to interfere with reception, at least until the turkey is cooked. This microwave oven interference is seen as short white lines or patterns of colored noise on the TV picture. This is one good reason to locate antennas on sites with few nearby microwave ovens, as on a high tower or on top of a campus engineering building.

Surprisingly Low Cost of Amateur Television Station Setups

One aspect of amateur television is the relatively low cost for setting up such a station. As noted, a receiving station with grid antenna and LNB plus 75 ohm cabling might run under $300, assuming you already have access to a commercial color TV receiver (otherwise add $99 for one from Circuit City). The 35 milliwatt ATV transmitter block costs circa $75-125 with case, and color TV chip cameras are another $50 or so. Add in $150 for a short length (50 ft) of cabling and a modest gain ATV antenna, and you are in business. A higher power 2 watt amplifier will add $200 or so to your station costs. You will also need a 12 volt power supply, a microphone, and a few other incidentals. Essentially, for less than the cost of a low end Windows computer system, you can have your own color television broadcast station. Now that's impressive!

Many amateur radio and electronics hobbyists will already have the receiving television set, color TV camera or camcorder, wireless microphone, 12 volt power supplies, and a VCR to record programs. A 2 meter radio with DTMF phone pad is frequently found in most amateur radio shacks too. If so, you will only need to add a Grid antenna and LNB converter plus some common 75 ohm coax to setup a receiving station ($150+). Add a transmitting antenna and coax ($150 +/-) and a transmitter ($75 up) and you are on the air.

Amateur Television Station Installation Project

Thanks to a generous donation of the Grid antenna, coax, and LNB block downconverter from Mr. Rik Albury (K4TTT), we only need to add a television receiver to be able to monitor the local AB5IG ATV repeater. Mont O'Leary (K0YCN) has also donated some 75 ohm coax for ATV operations.

We are hoping to arrange a TV receiver and VCR donation from surplus SMU engineering studio resources via club member Bill Hughes. We are looking into several sources for a TV camera, including surplus chip cameras from Networking and telecommunications dept. cameras.

Finally, we hope to be able to use club funds to purchase the currently installed high gain transmitting antenna "loaner" (circa $250). We need just 50 feet of low loss coax line with F connectors (circa $50+) and the ATV transmitter ($75-$125), amplifier ($250) and camera ($50-100) to put us on the air with ATV on a permanent basis.

Controlling the ATV Repeater

We should also mention that to fully control some amateur television repeaters such as AB5IG, you need a 2 meter ham radio walkie talkie or base station with DTMF phone pad. The DTMF phone pad generates tone sequences (e.g., *584) which control the various displays available on the AB5IG ATV repeater. Each repeater has its own set of codes and tones, so you need a table showing what functions are available, and how to make them work. Using such a chart, you can switch the AB5IG ATV repeater to show your own station broadcast full screen, show a 4 panel split screen, an image of the repeater control panels (e.g., to check your signal level to the repeater), or switch to service channels. Among these service channels are local North Texas radar station continuously updated scans and the NASA broadcast channel.

No Code FCC Technician License Requirements

Thanks to the use of microwave UHF and VHF control frequencies (e.g., 2 meters), you can get into amateur television with just a technician class license. As an entry level license, you do not have to know the morse code to get the required station license and your amateur radio operator license for ATV operations. Instead, you can take a no-code license option which only tests your knowledge of some entry level rules and some limited theory and good operating practice points.

Most no-code exam students will find the test pretty easy, especially since the entire pool of questions is published in study guides and available for pre-exam review. Even better, the answers are also published with the multiple choice questions, so your chances of passing the first time are very good. Exams are offered for a very nominal fee by local radio clubs and volunteer licensing coordinators and instructors at least monthly in the Dallas area.

You don't need to be licensed to use an amateur television station, provided a licensed operator is present and "in control" of station operations. That means that you can participate in amateur television station operations and programming and events, even though you are still working on getting your own entry level license. You simply need to schedule your visit beforehand, to ensure that a licensed operator is available and able to provide access to the station facilities (generally locked up, for obvious reasons).

Future Programs

What does the future hold for amateur television at S.M.U.'s W5YF ATV station? ATV is an entire new world of experiences for people interested in amateur television station operation or in the technical aspects of ATV and microwave electronics.

Frankly, most ATVers are hoping that we can attract some people who are interested in television programming. So you don't need to be some great technical genius with years of microwave experience to do fun and useful Amateur Television projects. We are especially interested in having students interested in radio and TV broadcasting and film making and the arts involved in using S.M.U.'s amateur television station W5YF.

In fact, thanks to S.M.U.'s Center for Media and Instructional Technology, you can create very neat mini-television program projects using programs such as Adobe Premiere. You can easily edit and piece together a video project, complete with professional fades and edits. Add text and CD-quality sound channels, and you have your own mini-television program project ready to show!

Updates on Amateur Television at SMU's Amateur Radio Club W5YF

Amateur television continues to make advances at Southern Methodist University's W5YF/ATV station and amateur radio club. Many of these ATV related updates are described in our various events pages (see main W5YF site). But we thought we should update and summarize these achievements here, since a number of pages link here from various web search engines and ATV sites...

After a successful funding proposal for a special capital funding effort in 2003-4, we were able to purchase a mini-DV Canon digital color camera and related ATV transmitters and support gear. We did so on the excellent advice of several local ATVers, particularly Rik Albury (K4TTT) and Mont O'Leary (K0YCN). The Canon model had the best warranty, impressive features, only free video software offer ($99 value), and ability to directly digitize from off-the-air and VHS tape sources. This camera was also the only one in this bottom tier mini-DV price class (under $400) to offer audio inputs other than from the built-in microphone. So the choice here was a no-brainer!

Thanks to a generous donation of the 1.2 Ghz beam antenna by Mont O'Leary, we were able to purchase a used 440 Mhz amateur television setup in addition to the AB5IG 1.2 Ghz amateur television repeater ATV system. This antenna donation also made it possible for us to get a combination NTSC fast-scan color TV camera and the Canon mini-DV digital recorder setup, rather than the separate color TV camera and nearly obsolete VHS format recorder/player we had originally specified. As a result, our digital recordings are much higher digital quality, and we can directly produce DVDs and high quality digital videos using programs such as Apple's I-Movie!


Major equipment additions to our amateur television station W5YF/ATV through July 2004 include:


As of July 2004, we also have an exciting digital video production on amateur television and remote control model airplanes on order. We plan to show this 90 minute video ATV program at an upcoming 2004-5 W5YF amateur radio club meeting.

We also have a used kenpro AZ-EL rotator (from an estate sale) on order (late July 2004) which we hope will resolve our satellite antenna requirements. If so, we will be able to dedicate our used Ham-M rotator and control box (donated by Robert Monaghan) to VHF/UHF, including ATV related uses.



In short, amateur television continues to be a focus of S.M.U.'s amateur radio club station W5YF. We hope to celebrate our 75th anniversary in 2005 with a high altitude balloon launch, perhaps including an amateur television transmitter in the payload. We will continue to produce videotapes of amateur related local events, for future amateur television broadcasts via the proposed national satellite amateur television network. Finally, as part of our 75th anniversary, we hope to interview some past club members and officers, capturing the history of our club on video for the future!

Email suggestions, updates, comments, links, and glitches to fix - Thanks!