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Helpful Tips

01/12/2004

Tips Title

Satellite Primer

How a Satellite-Assisted Broadcast Works

Terms

Where to View a Satellite Program

Technical Tips for Satellite Receiving Equipment

Receiver/Dish Adjustment Instructions for Some Popular Brands

Satellite Selection Chart for Typical Occasional Use Satellites

HOW A SATELLITE ASSISTED BROADCAST WORKS

The Origination Site
A satellite event originates live from a studio, or some other similarly “outfitted” facility (a place that has cameras and equipment for TV production).  From the studio, the video and audio signal either travels via fiber to an uplink antenna located at a “teleport” just outside the city, or to one located on the premises.  The uplink transmits the signal to the satellite.

The Satellite
For broadcasts, we use satellites that are in geosynchronous orbit 22,300 miles above the equator. This orbit is perfectly matched with the rotation of the earth, making it seem like the satellites are "fixed" above the earth.  There are two types of communications satellites:  C- and Ku-Band. They each have different frequencies, kind of like the difference between AM and FM radio stations.  The satellite you use depends on your network of receiving sites.

Viewing Sites
The audience attends the program at facilities equipped to receive the signal, i.e., they have a "receive-only" satellite dish.  The viewing room contains either large screen projection or TV monitors, seats for the audience and, sometimes, a phone or fax machine in the back of the room.  The audience sees the picture and hears the audio about a 1/4-second after the speaker actually speaks.  This is known as the "satellite delay." That’s because it takes approximately 1/4 of a second for the video and audio signal to travel at the speed of light the 44,800-mile round trip from the origination point to the satellite and back down to your location.

For Interaction
Calls, faxes and/or emails taken during the program and/or questions faxed or emailed in prior to the program. Each FDA program will announce how they will be taking questions.

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TERMS

The following terms refer directly to satellite programs and information contained in the Technical Fact Sheet provided for each program.

SATELLITE - For broadcasts, we use satellites that are in geosynchronous orbit 22,300 miles above the equator. This orbit is perfectly matched with the rotation of the earth, so it appears like the satellites are “fixed” in space above the surface of the earth. There are two types of broadband, analog communications satellites: C Band and Ku Band. Each type has its own set of uplink and downlink frequencies. You must know what band your program is on. Most contemporary analog downlink dishes can receive both C and Ku transmissions. Each satellite has a name – GALAXY, TELSTAR, etc.

AZIMUTH - The arc (east-west) in the sky where synchronous satellites are located. The position of a satellite is referred to as the “coordinates,” given as “degrees east or west.”

ENCRYPTION - (Scrambling) A television signal can be encrypted (scrambled). You would need a specific decoder in order to view the program. We do not encrypt/scramble our broadcasts. FDA programs are provided “in the clear.”

TRANSPONDER - A specific circuit on a satellite that receives an uplink signal, modulates it to the downlink frequency, amplifies the signal and transmits it back to earth. Satellites have at least 24 transponders.

LINEAR POLARITY – A technique employed to increase the capacity of a transponder. By alternating the shape of a signal (horizontal or vertical), one can double the carrying capacity of a transponder.

CHANNEL – When speaking of satellite transponders, “channel” is another way of referring to the polarized signal: horizontal or vertical.

DOWNLINK FREQUENCY – The radio frequency used to send a specific signal back to the surface of the earth. Each “channel” has an assigned downlink frequency.

AUDIO - Each satellite video channel has two audio channels. The radio frequencies are the same for all channels: 6.2 and 6.8 MHz

DIGITAL - A recent alternative to the broadband, analog signal. This type of satellite transmission utilizes small, receive-only dishes, locked or fixed on a specific satellite.  Direct Broadcast Satellites (DBS) are examples of digital services, transmitting direct-to-home in the 12 GHz range and beyond. At this point in time, we do not have access to these digital satellites. Our broadcasts cannot be downlinked using DBS dishes.

FOOTPRINT - A term to describe the geographic area (coverage) of a satellite signal.

TECHNICAL FACT SHEET – A document that provides all relevant information for the satellite program.  Sometimes, a Program Announcement is the only technical information provided.  An Announcement or Technical Fact Sheet for a satellite broadcast should include all of the following information.  If it doesn’t, check with the program provider to get the complete information.

  • Name of the Satellite (Galaxy 3C)
  • Coordinates (95 degrees West)
  • Transponder Number (Transponder 12)
  • Polarity (Vertical)
  • Channel (Channel 12 – the vertical polarized signal of Transponder 12)
  • Downlink Frequency (3940 MHz)
  • Audio Frequency (6.2 or 6.8 MHz)
  • Trouble Number (The national/origination phone number for technical support regarding reception-problem questions.)
  • Phone-in and FAX numbers (for asking questions during the program)

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Where to View a Satellite Program

Ways to view the program

There are several possible ways to view the program:

  • Attend at an Open Site, if there is one near you.  We publish a show-specific list based on registration for each event.  Check with the show of interest (DCM calendar home page).
  • Watch at your own facility by:
  • Find a local site where you and your colleagues can view it.

Finding a Local Site

If there are no Open Sites near you and you don’t have the ability to view it at your own facility, you will need to find a local downlink/viewing site to agree to bring in the signal for you and your colleagues. 

To do that, first, print the Technical Fact Sheet for this event.

Second, contact local folks in your area (see “Places to Try” [below] for ideas).

What do I need to say to potential sites when I call them?

Tell them:

  • who you are and who you represent;
  • that you are inquiring if they can be a receive/viewing site for a satellite event on (fill in the date);
  • and which satellite(s) it will be on. 

If you get through this basic information without them telling you that they cannot do it for you, you can continue on through the litmus of information that follows:

Tell them:

  • that you need the room from the beginning of the test time through to the end of the program (check the Technical Fact Sheet -- make sure you use your local time, not just the first time listed);
  • how many folks you expect to have and then ask if they have enough (or large enough) monitors or screens for that many;
  • that you need to be handicap accessible (this may include elevators, ramps and/or a closed caption decoder on the monitors/large screen), if applicable;
  • that you would like the use of a phone in the back of the room for interaction, or close proximity use of a phone or fax machine.

If you are able to book a site, there are still a few questions to ask them:

  • Who is your Technical contact during the program?
  • Will that person remain on site until during the entire program?
  • If not, how will you be able to reach them if you encounter a technical problem during the event? (Contrary to what some may tell you, just because someone sets the dish up for the test and program, it does NOT mean that nothing untoward can happen after that!)

Places to Try:

  • Other government offices/agencies (for instance, Bureau of Land Management offices are available for other gov’t agencies to use for satellite events)
  • Community Colleges
  • Junior Colleges
  • Universities
  • V.A. Hospitals
  • Technical Schools
  • Libraries
  • Schools/School District Offices
  • Public Television Stations
  • Fire/rescue stations
  • County Health Departments
  • Cinema houses (those that have a satellite dish on their premises)
  • Restaurants with Satellite Dishes on Their Roofs
  • Local National Guard Armory

Be aware, some of these sites may want to charge a fee to use the facility.

You may e-mail us to ask for a specific referral in your area. We will get back to you with some names and numbers, if we know of any near you. (Take care in entering your email address, otherwise we won’t be able to get back to you.)

Using a Transportable Satellite Dish
You can also rent a transportable dish. A transportable would pull up to your building and park for the day. You will have to supply a monitor or projector and screen or you can rent one from the same vendor. The dish needs to have an unobstructed southern “look” at the sky. The cost for renting a transportable dish can run between $500 and $1200/day, depending upon your city and the length of the cable run. These services can usually be found under “satellite” in your local yellow pages.

Using a Videoconference Room for a Satellite Event
If you have a digital videoconference room, you may be able to participate using your equipment. You will need to make arrangements with a “Bridging” service to downlink our program and put it through to your room. There are several companies that provide this “Service.” Ask your video conferencing coordinator or IT Manager to contact their digital line provider for assistance.  In addition, there are several other commercial bridging services.
E-mail us for a referral.

Be aware:  there will be an extra fee involved for this service, even if it’s your regular provider.

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Technical Tips for Satellite Receiving Equipment

Basic knowledge

1. When preparing to receive a satellite broadcast, one of the most important things to know is Murphy’s law and then expect the unexpected.  Do NOT wait until program test time to see if your equipment is functioning properly. One of the ways to see if your satellite dish is still pointing properly is to try to tune in:

  • Galaxy 4R (G4, G6 or G2 on your receiver)
  • Channel 15 and 16 (Religious programming)

If you can see Channel 15 but not 16, you could have a polarity problem. Try to change your polarity yourself (see Receiver/Dish Adjustment Instructions below). If you still cannot see Channel 16, you will need to have your dish serviced.

If you can see Channel 16 but not 15, the same rules apply.

This will not guarantee that you will be able to see a program on another satellite, but at least you will know if your dish has blown “off-satellite.”

2. Although it varies slightly by your geographic location, there are approximately 18 – 24 digits of difference for every 2 degrees of satellite spacing.  So if you need to move your dish manually and you know how far you need to move it – i.e., 2 degrees – then right down your dish position before starting and either add 18 or subtract 18 from the number (going West, you add; going East, you subtract) as a starting point to find your program/satellite.

3. If it has been snowing, your dish may be filled with snow. This will cause poor reception because receiving a good signal relies on the reflection capabilities of your dish.  Clean it out if possible, or you will have to live with the poor reception.

4. If your dish is located on the ground and has been there for many years, trees may have grown up in front of it, blocking clear reception.  Make sure that you have an unobstructed view to the South.

5. Make sure your receiver remote control has good batteries and that you have a back-up remote control in case someone loses or misplaces one.

6. Make sure your receiver remote control has the volume level as high as it can go.  All audience volume adjustments should be made on your monitor or speaker system, NOT via the satellite receiver.

7. Make sure that whoever is charged with tuning in the satellite program knows how to operate the equipment. If that is not possible, make sure that a technical person is available in case of difficulties.

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Receiver/Dish Adjustment Instructions for Some Popular Brands

To “Manually” move your dish

    COMMANDS for Chaparral

      MENU
      #7 SAT/CHAN SET-UP MENU (if it requires a passcode, use 2345)

      The arrow should be pointing at “DISH POSITION.” If so, press ENTER to activate that field and right down the 4-digit number (just so you know where you began)

      Use your right or left arrow buttons to make the numbers go up or down.  (For instance, if you know you need to go West, the numbers need to go up; to go East, the numbers need to go down.)  BIG HINT:  there are typically between 18 and 24 digits for every 2 degrees of satellite position, so adding or subtracting 18 digits is a good starting point.

      Once you have found our program, center on the best signal, press MENU twice quickly to set in your change.

      Press MENU slowly several times to get you out of this menu function.

      NOTE:  your model/options could be different.

    COMMANDS for General Instruments (GI) 4DTV

      OPTIONS

      ADJUST PICTURE

      DISH POSITION

      Use your right or left arrow buttons to make the numbers go up or down.  (For instance, if you know you need to go West, the numbers need to go up; to go East, the numbers need to go down.)  HINT: there are typically between 18 and 24 digits for every 2 degrees of satellite position.

      Once you have found our program, center on the best signal, press ENTER to set in your change.

      Press EXIT or GO BACK to get you out of this menu function.

      NOTE:  your model/options could be different.

    COMMANDS for Older Model General Instrument (GI)

      MENU

      INSTALLATION

      PROGRAM SATELLITE

      DISH POSITION

      Use your right or left arrow buttons to make the numbers go up or down.  (For instance, if you know you need to go West, the numbers need to go up; to go East, the numbers need to go down.)  HINT: there are typically between 18 and 24 digits for every 2 degrees of satellite position.

      Once you have found our program, center on the best signal, press ENTER to set in your change.

      Press EXIT or GO BACK to get you out of this menu function.

      NOTE:  your model/options could be different.

To Change Polarity (also known as “Skew”)

    COMMANDS for Chaparral

      MENU

      #7 SAT/CHAN SET-UP MENU (if it requires a passcode, use 2345)

      Use your arrow keys to move the pointing arrow down to “POLARITY.”   Then press ENTER to activate that field. Typical settings for polarity are 101 and 176, for these receivers.  If yours says something different than one of those, try going to one of them (the closest number to what you are seeing), before trying the other number. If yours says 101, try moving it to 176 to see if it solves your problem.  You use your right and left arrow keys to move the numbers up and down.

      Once you have found our program, center on the best signal, press MENU twice quickly to set in your change.

      Press MENU slowly several times to get you out of this menu function.

      NOTE:  your model/options could be different.

COMMANDS for General Instruments (GI) 4DTV

      OPTIONS

      CHANGE SYSTEM

      INSTALLATION SETTING

      CHANGE DISH

      FEEDHORN

      You should end up with a choice of “STANDARD” or “ROTATE DISH 90 degrees”. Select “ROTATE” so that your polarity changes.

      Press EXIT or GO BACK to get you out of this menu function.

      NOTE:  your model/options could be different.

COMMANDS for Older Model General Instrument (GI)

      MENU

      SATELLITE ADJUSTMENTS

      DISH OFFSET

      FORMAT REVERSE

      SKEW

      Look for how you can ROTATE or change the polarity/skew.

      Press EXIT or GO BACK to get you out of this menu function.

      NOTE:  your model/options could be different.

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For your convenience, here is a chart, in alpha order by satellite, which you might find helpful. Just remember, it’s more important to be at the right location than to have it called a specific name. If your receiver uses a different code to get to these, mark it in this chart and have it handy for anyone who may be tasked with bringing in a program.

Satellite Selection Chart for Typical Occasional Use Satellites

 Satellite

Receiver Code

Orbital Slot

Band

AMC-1 (GE-1)

 W1

103 degrees West

C

AMC-1 (GE-1)

K1

103 degrees West

Ku

AMC-2 (GE-2)

 W2

105 degrees West

C

AMC-2 (GE-2)

K2 or R4
(G-Star 4 used to be at this location

105 degrees West

Ku

AMC-3 (GE-3)

 W3

87 degrees West

C

AMC-3 (GE-3)

K3

87 degrees West

Ku

AMC-4 (GE-4)

 W4

101 degrees West

C

AMC-4 (GE-4)

K4

101 degrees West

Ku

AMC-9 (GE-3)

W9 or W2

85 degrees West

C

AMC-9 (GE-3)

K9 or K2
AMC-2 used to be at this location

85 degrees West

Ku

Galaxy 3C

G3

95 degrees West

C

Galaxy 3C

X3
Galaxy 3R used to be at this location

95 degrees West

Ku

Galaxy 4R 

 G4 or G6

99 degrees West

C

Galaxy 4R 

X4 or X6

99 degrees West

Ku

Galaxy 11

GB or G7

91 degrees West

C

Galaxy 11

XB or 08 (zero 8)

91 degrees West

Ku

Galaxy 13

G9

127 degrees West

C

Galaxy 10R

G0 (G zero) or G9

123 degrees West

C

Galaxy 10R

X0 (X zero) or X9

123 degrees West

Ku

SBS 6

06 (zero 6) or B6

74 degrees West

Ku

Telstar 5

T5

97 degrees West

C

Telstar 5

L5

97 degrees West

Ku

Telstar 6

 T6

93 degrees West

C

Telstar 6

L6

93 degrees West

Ku

Telstar 7

 T7

129 degrees West

C

Telstar 7

L7

129 degrees West

Ku

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