Section 1: Technical and Need-to Know

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Copyright 1996, Dr. Albert E. Powell, Jr.
Assistant Director, Distance Learning Development
Colorado State University, Fort Collins, CO 80523-1040

SATELLITE TERMS EXPLAINED

Program announcements about a satellite broadcast will include information similar to this example:

Title: The National Armadillo Test
Source: Texas BBQ University
Date: Jan. 3, 1999
Time: Test 12:30 - 1:00 pm ET, program 1:00-2:00 pm ET
Satellite: Galaxy 7, Trans. 19-Horiz., Chan. 19
Downlink frequency: 4080 mhz
Audio: 6.2, 6.8
Trouble: 409/845-5611

Title: Be specific! Many programs have similar titles, and some are parts of a series. Be precise to avoid problems.

Source: The producer or the originating site. A producer can be a company, association, university, or some other person or entity. The originating site may not be not listed, because it's not very relevant to receiving the event. The broadcast may be uplinked from a site different than the producer's home base.

Date: Obvious. Remember that you can tape broadcasts when you can't view them live!

Time and Time Zones: WATCH OUT! The standard time for satellite listings is Eastern Time, so program times usually have ET next to them. Convert ET to your time zone as needed.

In the listing above, 12:30 - 2:00 pm ET is 11:30 - 1:00 pm Central Time (CT). However, a producer may give their program time in Central, Mountain or Pacific Time. ALWAYS, ALWAYS double-check this, and convert carefully! In this example, the first 30 minutes is a test feed provided for you to make final adjustments to your downlink. The program starts after the test. If the listing doesn't specify a test period ask about it, because otherwise you won't know when the program really starts!

NEED-TO-KNOW #1: What is the program time in YOUR TIME ZONE?

Satellite: There are many satellites, all designated by a name and additional numbers or number and letter combinations. For instance, there are two Spacenets (Spacenet 3 and Spacenet 4) and four satellites in the G-STAR series (G-STAR 1, 2, 3 and 4). Some have names like Telstar 302, Satcom F2R, and Anik E2.

Check the satellite's name and number at your viewing site. They can be identified differently in each satellite receiver. Example: T1 at one site may be listed as T4 at another site!

Channels and Transponders: Transponders and channels are not the same thing. This confuses many people, and so does the fact that there are C-band and Ku-band satellites (more on C and Ku on the next page). Every satellite has transponders; most C-band satellite transponders have two channels, and each channel can carry a different program.

You might think of a transponder as a highway: two programs or channels can travel on it at one time. Because of this, a satellite with 12 transponders usually has at least 24 channels. The terms used to specify the program's broadcast are Channel X, horizontal or vertical. Here are some C-band examples:

But wait! There's more!! On Ku-band, some transponders can carry up to three signals. (Sorry about that.) In these cases, tuning by downlink frequency is usually the best and easiest way to bring in the program. For instance, on Telstar 4, transponder 11 can carry three signals, each differing in frequency. (And all three are vertical, which is different than on C-band satellites.) Unfortunately, Ku-band transponders are less consistent than C-band as to the number of channels per transponder. For this reason, it really pays to test them ahead of time and make sure you can receive the program.

Downlink Frequency: This is the radio frequency at which the program is carried. If you can't find the program with your receiver's existing setup (like when there are three channels on a transponder...) this information becomes critically important. Many receivers allow you to enter the downlink frequency manually, bypassing the channel assignments. When your receiver was installed, the technician assigned a frequency to each channel. If the channel's assigned frequency changes, you can override it by entering the correct information. If you can't find the program any other way, try entering the downlink frequency manually. (Refer to your receiver manual for the procedure.)

Polarity: Remember the horizontal and vertical terms which go with channel assignments? These are called the polarity. The polarity was also assigned to each channel when the technician installed your downlink, and it could be programmed incorrectly, or the satellite setup may change. Most receivers allow you to manually set the polarity for each channel. If you can't find a program after you've tuned in by frequency, the next thing to do is to check the polarity on that channel and try changing it to see if the program comes in.

Important: get the downlink frequency; if you don't see the program, check the polarity!!

The more you watch Ku-band satellites, the more you need to understand transponders, channels and polarities. Since receivers tune by channel but channel assignments can change, it's important to know how you can override the channel presets and find a signal by entering the frequency.

NEED-TO-KNOW #2: Make sure you know the SATELLITE, CHANNEL and DOWNLINK FREQUENCY for your program.

Audio: Each program channel has stereo (two channels of audio) capability. You normally don't have to worry about this. However, in some cases, one audio channel may be used for a second language broadcast of the program. In that case, use your receiver manual and find out how to select only the audio channel you actually want to hear, because you won't want to hear both at the same time. You usually will see a notation that a program has "audio at 6.2 and 6.8 MHZ" meaning that both audio frequencies are carrying the same information.

Trouble Number: This is the number at the satellite uplink (origination) site. You might call it under these conditions:

  1. If you can't find the test signal or program. Programs are sometimes moved to a different satellite with little notice. (This is one reason test signals are used - to discover problems before the program starts - and call the trouble number if necessary!)
  2. If there's a problem with the signal that does not seem to be due to your site's equipment. There may be a problem at the origination site or with the satellite.
  3. If the program begins OK, then develops a problem such as severe interference, "snow" or double images. There may be a problem with the satellite that the origination site hasn't caught yet, but double-check your equipment before calling. It's more likely that something has gone wrong at your receiving site.
Please don't call the trouble number for help unless you need it. They are not there to tell you how to turn on or tune in your downlink equipment; that's up to you. 

SATELLITE BANDS AND COMPATIBILITY

There are two satellite bands, C and Ku (both letters are pronounced in Ku: Kay-You). These are different radio frequencies, like AM and FM radio. Just as you can't hear an FM radio station on an old AM-only radio, you can't receive a Ku-band program on a C-band dish. Many older or homeowner downlinks are C-band only; many of the newer homeowner, educational and industrial sites have downlinks which receive both C and Ku. You must make sure the downlink you will use to view a program can receive the needed band. Satellites can be C-band, Ku-band, or both (dual-band). The satellite program announcement specifies which band is used for transmission.

NEED-TO-KNOW POINT #3: On what band is your program: C or Ku?

Some programs air on both bands so that any downlink can receive them. Receiving C-band is usually easier as dish aiming is less critical, but C band is can be interfered with by local electrical or microwave signals. Ku-band is less susceptible to electrical interference problems, but extremely heavy rains over the receive site can disrupt Ku reception. If your program is carried on C-band, it should be easy to find a compatible downlink. If the program's on Ku-band, you'll have to look harder for a downlink and ask specifically whether the site is Ku-capable.

When you plan to use a downlink site, check with the site well before the event and confirm they can receive the band your program will be on, especially if it's only available on Ku-band. This can bite you! Because many people don't understand their downlinks very well, don't accept someone's vague impression of whether the downlink is compatible with your broadcast; confirm the facts with someone

NEED-TO-KNOW POINT #4: Confirm that your downlink can receive the band and satellite, especially for Ku broadcasts.

SCRAMBLING

Some satellite broadcasts are scrambled (industry term: encrypted) so that a compatible decoder on the satellite receiver is needed to view them. Viewing these programs requires you to carry out the following steps.
  1. Confirm that the receiver at this viewing site has a decoder, and find out what the decoder's ID number is.
  2. Register as a viewing site, and give them the downlink decoder's ID number. During the test period before the program, the producers will feed a digital code which activates the receiver at each authorized site. This enables the decoder to receive the program.
  3. you don't get a clear picture early in the test period, call the trouble number immediately and ask to re-enable your decoder. They will feed the digital code again, which should solve the problem.
NEED-TO-KNOW POINT #5: To view a scrambled broadcast, confirm the site's de-scrambling capability and get the decoder's ID number to the registration site.

MEETING SITES

The best physical layout for a viewing site depends on the number of viewers and the activities involved. A home's living room is fine for a half-dozen people for a lecture-type program, but if the program involves group activities and meals, you need a larger facility with room to operate.

Making the decision on a facility depends not only on what the satellite program requires, but also on whether you plan to conduct local programs or activities. If you add local activities, you are likely to need different tables and chairs, meeting rooms, or A/V aids such as newsprint charts or overhead projectors.

NEED-TO-KNOW POINT #6: Match the viewing site, seating and facilities to the activities planned for the entire program, not just for the satellite broadcast.

VIEWING EQUIPMENT

Important rule of thumb: have one inch of viewing screen for each viewer. This means for 25 viewers, you need at least a 25 inch screen TV. Don't forget to arrange the seats and elevate the screen so that all 25 can actually see it!

For up to 50 people, the easiest solution is usually to use 25 inch monitors connected to the program feed. A more impressive option is to use a video projector, which shoots the picture onto a projection screen, or even a light-colored wall.

Most video projectors can produce image at least 100 inches (diagonally), and they can safely serve at least two people for every diagonal inch of screen size: a 100 inch image can serve 200+ people, and requires a 5'x7' screen or a similar sized area on a light-colored wall which can substitute for a screen. The main drawbacks of video projectors are:

  1. To have a clear image on the screen, you must be able to darken the room as much as you would for a slide show.
  2. Projectors are expensive to rent ($100+).
  3. Some projectors (three-lens type) are a bit complex to set up; one-lens LCD types (the Sharp line is common) are easier to use. Because of setup, if you plan to use a projector, learn how to use it before the day of the meeting.
  4. You must have a large screen or light-colored wall to serve as a projection surface, and the audience must have a good line of sight to it.
  5. The speakers built into many projectors are not loud enough for large crowds. Test the projector by playing a videotape through it; watch the picture and listen to the audio, and decide whether you need to feed the audio into a separate PA system. Remember that adding people to the room cuts down the sound bounce, so you'll need to turn the sound up higher than when the room is empty.

NEED-TO-KNOW POINT #7: TV monitors are practical for up to about 50 people. For larger groups, video projectors are better, but expensive to rent. Make sure your audience can hear and see well from all the seats.

Line of sight problems are very common in setting up viewing equipment. Make sure to elevate the video display (monitors or screen) high enough that viewers can see over the heads of those in front. This usually means elevating the screen at least three feet off the floor. When using a video projector, make sure you can dim the lights and drape the windows to darken the room suitably.

NEED-TO-KNOW POINT #8: Elevate your video displays to provide unobstructed viewing. If you use a video projector, test the room lights to make sure they can be controlled and won't "wash out" the screen.

TELEPHONES AND FAXES

The telephone is your lifeline to the satellite world. You absolutely must have access to one to call in questions or get help with technical problems. Some programs also require that viewing sites have a fax machine in order to participate; find out what is needed well before the event. If the program involves live Q&A, need to have a phone available in the viewing room. If not, you only need access to a phone so you can handle technical problems. If there's no phone in the room, you may be able to run a long phone cord from a nearby office; just tape it down so people don't trip over it. If that doesn't work, you might use a cordless phone (heck, you might even bring one from your home). Another option is to borrow or rent a cellular phone for the day. If all else fails, you can have a phone line installed in the room.

NEED-TO-KNOW POINT #9: Don't forget phone and fax access. Always know where the closest phone is.

OTHER A/V EQUIPMENT

The activities planned for your satellite program may require a PA system, slide projector, flip charts or newsprint sheets, other A/V equipment or materials for demonstrations. Plan ahead and make sure that everything is scheduled, present and working. (An overhead projector with a burned-out bulb isn't much good.) 

PLAN AHEAD - WHAT TO CHECK

The most common mistake is waiting until the last minute before testing the downlink, video and audio equipment. The thing you're most likely to forget about is the telephone, so check it early!

For maximum safety, it's great to test the downlink about one week before the event, and test it again the day before the event. If possible, leave the downlink set up from the day-before test. If the channel for your program will be scrambled, test the downlink by looking at another, non-scrambled channel on the same satellite. This will pre-set your dish on the correct satellite and you can easily change channels.

On the day of the program, have the downlink tuned in, all equipment turned on and in place, and everything checked at least one hour before the program. That's all you can do until the test signal comes up, usually 30 or 15 minutes before the program. During the setup and the test signal, have someone else present so you can deal with any satellite problems and the other person can handle the people arriving for the program.

NEED-TO-KNOW POINT #10: Test the downlink ahead of time. Have all equipment in place and completely tested at least one hour before the program. Have a helper present during the test signal.

LEGAL POINTS

Before you record any satellite broadcast, make sure you have the legal right to do so. If it's free, there is a good chance that you can videotape it with no legal problems, but ask first! If you have to pay to receive the program, there will probably be restrictions on videotaping it. If your own company or institution originates the broadcast, it's usually safe to assume you can tape it for use within the company.

The legal problem is often not in taping the actual broadcast for your audience, but in making copies. Regardless of whether you were given permission to videotape a program or not, that program is covered by copyright law just like a book. You can only use the program in ways permitted by the producer. Unless you have specific permission, don't copy the tape. Refer any requests for copies to the program's registration site or producer.

NEED-TO-KNOW POINT #11: All satellite programs belong to the producer and are covered by copyright law. Do not make copies of them; refer inquiries to the registration site.

FINDING A SITE AND GETTING TECHNICAL HELP

Your institution or company doesn't necessarily have to own a downlink. Downlinks are available all over the country, and many owners will let you use them. The best places to find downlinks are public grade schools, high schools, colleges and universities, and some hotels. In many cases, a local TV cable company will downlink the program and deliver it to your site via the cable - talk about convenient! (You can have a cable connection installed in most buildings for a small fee, if there's no cable drop there yet.) Even if there's no downlink available at all, you can rent a trailer-mounted downlink, although this usually costs more than $500 per event.

If you have technical problems, a local satellite vendor or downlink owner probably knows how to solve them. Use your personal networking talents to find help and identify local people who can help you solve problems. You can always call the company which built the receiver and ask them for help; most of them have technical support staffs. If you have to pay a local satellite vendor to come solve a problem, that's the cost of doing business. It's better to receive the program than to miss it - and all equipment hiccups sometimes.

NEED-TO-KNOW POINT #12: You have local resources, including viewing sites and satellite service vendors. You can also call the manufacturer for help. Know your options.

That's it for the Need-to-Know section. There's more information on many of the topics touched on here, if you'd like to look in the other part of this reference, the "Nice-to-Know" section. This section contains more troubleshooting information for downlink problems, and contains a Glossary.

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