SAREX Field Operations Guide


This guide was developed to aid participants in SAREX prepare for and carry out a SAREX contact. There are many things which go into making a successful SAREX contact between earthbound students and Shuttle crew members. This guide covers the broad spectrum of topics that are intrinsic to SAREX. Therefore, this guide is for a wide audience of readers, from the amateur radio operators who provide the techncial support, to the teachers and school administrators who utilize the educational aspects of SAREX to benefit their students. For readers participating in the ARRL/AMSAT/NASA sponsored program which utilizes SAREX to provide a pre-arranged contact with Shuttle astronauts, this guide should serve as your principal reference source. It has been written to assist your team through all phases of a SAREX contact, from submitting the application and proposal to the post- contact details.

The main goal is to make your SAREX contact a successful and stimulating educational experience for the students. Students and the local community alike should derive maximum benefit from the SAREX experience and this guide will serve to help you achieve that goal. If you are participating in SAREX for your own enrichment by attempting contact with the Shuttle astronauts or the packet robot during unscheduled, random opportunities, this guide is also for you. While it is principally written towards the scheduled school contact program, it contains a wealth of information that will assist you in your efforts. Most of the technical information on station construction is applicable and there are special sections which are written solely for the support of individual amateur radio operators who are attempting their own, unscheduled contact.

Whatever your reason for participating, you will surely find this guide invaluable to your sucess. The sound of your callsign coming back to you from space is an experience unmatched by any other.


The Shuttle Amateur Radio Experiment (SAREX) program is a highly visible and successful program which allows students from all walks of life to talk directly with Space Shuttle astronauts as they orbit the earth on space missions. SAREX is a mid-deck Space Shuttle payload sponsored by the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL) and the National Aeronautics and Space Administration (NASA). From its initial flight in November, 1983, SAREX has matured from a pure experiment, with infrequent flights to become an operational Shuttle payload, now flown several times each year. Since the STS-45 shuttle flight in March, 1992, SAREX has been carried aloft or is planned for nearly half of all shuttle flights. SAREX provides the students with a positive learning opportunity, sparking interest in science, technology, and communications fields by allowing them to talk directly to Space Shuttle astronauts using amateur radio. This event could be the spark that launches a child into a career in science or technology, a child who someday grows up to provide a very significant contribution to the world through his or her work. A SAREX contact will surely become something every child and adult alike who participates will remember for the rest of his or her life. In addition, SAREX showcases amateur radio, conveying the technical knowledge which can be gained from the amateur radio hobby, and demonstrating the public service that hams can provide. It is an opportunity to demonstrate the things that are possible in amateur radio using a very dramatic and highly visible and stimulating experience. SAREX further provides increased public awareness of NASA's manned space program by permitting radio amateurs worldwide to talk with the Shuttle astronauts. NASA's intent in making astronauts available for SAREX operations is to involve the largest possible numbers of people, particularly youngsters, in technology and the US space program with the help of Amateur Radio. Literally thousands of hams and students, in the USA and other countries including Russia, Germany, the Netherlands, the UK, Norway, South Africa, Japan, and India have directly participated in SAREX, and many have been rewarded with the unique opportunity to talk directly with an astronaut working in space.

During a SAREX mission, the astronauts will typically make the following types of Amateur Radio contacts:

A handful of schools are selected from around the world to make contact with the shuttle during most SAREX missions. These contacts are prearranged, giving the schools a greater chance at making a successful contact. Two or more students at each of the selected schools ask questions of the astronauts during the contact. The nature of these contacts embodies the primary goal of SAREX--to excite students' interest in learning.

SAREX Contact Intent and Format

A scheduled SAREX contact is intended to be used as the centerpiece in an educational program that will involve as many students as possible. The program should utilize ham radio wherever possible, but can cover any topic related to amateur radio, space flight, or the primary payloads for the shuttle mission involved. All events and lessons in the program should be built around the actual contact with the astronauts. This contact will last no more than eight minutes and will be conducted between one crewmenber and your students. For that precious eight or so minutes, your school and students have the full and undivided attention of an astronaut in space. The astronaut will be present to talk only to your school and answer your questions exclusively. The format of the contact is most commonly a question and answer session, essentially, an interview of the astronaut conducted by the students. Following the contact, the educational program should conclude with a follow-up to reinforce the lessons learned.

Contact Link Methods

Your school may be linked to the Shuttle astronauts via either a Direct Contact or a Telebridge Contact. The method used for your contact will depend on many factors, the most important of which being visibility of the shuttle in your area and the work schedule of the Shuttle astronaut crew. In a direct contact, voice contact is made with the Shuttle astronauts from an amateur radio station set up at your school. Your group is responsible for all of the technical details required to communicate with the Shuttle. In a telebridge contact, your school is linked by telephone to an amateur radio station elsewhere in the world. This amateur radio station handles all the details of contacting the Shuttle astronauts, and is called the Telebridge Station. The telebridge station's speaker and microphone are extended to your group over the telephone line to the students. This operation is much like what radio amateurs call a phone-patch.

Direct Contacts

Direct contacts require extensive planning and a considerable investment of time to plan, prepare and execute. A direct contact requires that you design and build a complete VHF earth ground station complete with automated antenna control, install this station at a remote site (school), and handle all the details for contacting the shuttle, maintaining that contact, as well as managing the students during the contact. However, a direct contact is the most rewarding for because your group has taken responsibility for and accomplished all aspects of the contact. Your group has established its own, private radio contact between yourselves and the Shuttle, something that until SAREX came along, was enjoyed exclusively by NASA. A direct contact provides the highest level of direct exposure to amateur radio to the students that the SAREX program offers. Students can gain considerable hands- on experience in numerous science and technology fields and apply them directly.

Telebridge Contacts

A telebridge contact relieves your group of much of the responsibility for the most difficult aspects of a SAREX contact. The telebridge station operator, part of the AMSAT SAREX team, assumes that responsibility for you. This frees your group to concentrate on the other aspects of the contact, attempting a more diverse set of educational projects in conjunction with your school’s SAREX pass that you might not have had the time or resources to accomplish if your contact had been a direct contact. Exposure to ham radio is accomplished using through the support activities and a simulated direct link. While your group is not handling the satellite communications aspects, a significant amout of engineering is required to design, install, and support the equipment necessary to provide the simulated direct link. The simulated direct link places the students at an amateur radio transceiver in a central location with all of the other students and spectators. This radio is used to communicate with a second amateur transceiver located in a back room where the telephone lines connecting you to the telebridge are located. In this way, the students are provided with the"look and feel" of a direct contact much as the astronauts themselves use simulators during their training. Further, the students gain direct exposure to amateur radio that they would have not had if your group had used a telephone teleconference format.
It is important to note that NASA planning considerations can cause a direct contact to be rescheduled during flight as a telebridge contact. Further, the telebridge format is often used in the event that your first attempt at contacting the shuttle fails and a second attempt is necessary. This second attempt is called a backup pass. Backup passes are described in more detail in Section X.X. Because of this possibility of rescheduling and a possible need for a backup pass, all groups must be prepared to support a telebridge format contact. This applies even if your group is notified that your contact will be a direct contact format.

SAREX Configurations Summary

This section provides a summary of the various configurations, or flavors, of the SAREX equipment flown on board the shuttle. Different configurations will be flown on different missions, depending on a number of things. These considerations include Shuttle weight, power, and balance considerations, mid-deck locker stowage space, the number of ham astronauts onboard, and crew availability for attended operations. For a more complete description of the SAREX flight gear, see the references at the end of this guide.

There are five configurations of the SAREX flight gear. Each offers different capabilities. Configurations differ in their use of the various components of the total SAREX flight gear set. Table 1 summarizes the capabilities of each configuration. Figure 7 illustrates each configuration.

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