![[VASC Satellite Station Exhibit]](../images/s_vascex.jpg)
The VASC amateur radio satellite station operates 24 hours a day utilizing digital communications with three, Mode J, 9600 baud Packet satellites which are designated as UO-22, KO-23 and KO-25. Packet communications are similar in many respects to Email. Manual operation in Mode B or J, as well as simplex, is available for communicating with other Amateur Radio satellites such as AO-10, AO-13, and the Russian Space Station Mir.
One other favorite Amateur Radio satellite is designated as AO-13. This satellite is in a highly elliptical orbit and as a result is available for several hours daily for communications. Unfortunately however, AO-13 is expected to return to the atmosphere and burn up in November 1996. AO-13 has been in orbit since June 1988 and has provided many thousands of contacts between Hams around the world. The station keeping fuel supply is depleted and neither attitude nor orbit can be adjusted to prevent reentry.
The three 9600 baud digital satellites UO-22, KO-23, and KO-25 are in polar orbit at altitudes between 491 and 817 miles above earth. These satellites complete an orbit in approximately 100 minutes each. Each one of these satellites make six or more passes a day over the station location, but generally only two or three of these passes permit the reception of strong signals. The calculation of satellite passes is accomplished by running a program called Instant Track along with other programs such as Satsked, Satlink, View-Dir and a Packet communications program. These software packages are available from the Amateur Satellite Corporation of North America (AMSAT-NA) located in Silver Spring, Maryland.
The digital satellites provide a mobile space-borne mailbox for Hams around the world to discuss equipment, computer programs, and other interesting subjects. Images of the operators, scenery etc., are also frequently exchanged. Satellite operators can check and answer their mail daily at their convenience. Weather and sunspot activity do not hinder communications. Additionally, several amateur radio satellites are equipped with cameras. Interesting images of earth scenes have been taken from space.
Individual hams who are designated as Control Operators are responsible for the smooth operation and training of new operators to occupy the station during peak visiting hours at the Virginia Air and Space Center. A station operator can be made available by request for special groups that visit the Virginia Air and Space Center.
When the station is not manned, the station computers still track and communicate with UO-22, KO-23 and KO-25. The computer clocks are kept accurate by time signals from UO-22. All three satellites permit the download (reception) and uploading (transmission) of files. Any messages that are marked for station KE4ZXW are received automatically. While many messages are received daily, some of the more interesting messages and pictures are kept in a notebook for display to visitors.
When a control operator is not present, station visitors may depress a button on the visitor's console to bring up a slide show which includes a narrative depicting the entire history of Amateur Radio from the spark transmitter days, and short video clips about the space program. These presentations feature the Hams that are involved and even bring up a world display showing the real-time location of five selected satellites including the Russian Space Station Mir. After the map presentation is complete, selected messages received from the amateur radio satellites are shown on the visitor's display.
During satellite communication operations the station operator can display the location of the selected satellite or simulate the next pass of a selected satellite. This allows our visitors to better understand the satellite communications process as the tracking computer follows a satellite pass. Other features of the Instant Track program include the ability to display tracking charts, orbit diagrams and forecast satellite passes several weeks into the future.
A visitor's register has recently been implemented to record the presence of other hams and our foreign visitors. This register has already indicated visitors from Germany, South Africa, England, Holland and many other countries. Several mariners that live and cruise on sailing craft have also visited the Virginia Air and Space Center satellite station. They are fascinated to learn that there is a growing group of sail and power boat satellite stations.
The station was recently visited by US Astronaut Dr. Kathryn Thornton, who has accumulated 593 hours in space flight and 21 hours outside the Space Shuttle while working to repair the Hubble Space Telescope. Also, former US Astronaut Dr. Norman Thagard has visited as well. Dr. Thagard spent 105 days aboard the Russian Space Station Mir as a cosmonaut researcher studying space flight physiology.
A select group of Hams are actively involved in the Shuttle Amateur Radio Experiment (SAREX). This program is jointly governed by the National Aeronautics and Space Administration (NASA) and the American Amateur Radio Relay League (ARRL). The SAREX program organizes and trains groups of students in communications with space vehicles and then, after the proper scheduling arrangements are made are permitted to utilize a station like KE4ZXW and to talk directly with Amateurs aboard the Russian Space Station Mir or one of the US Space Shuttles.
The satellite station antenna system consists of two crossed yagi's with mast mounted pre-amps. These antennas are controlled by special satellite tracking azimuth and elevation rotors. The tracking computer is a 386 class PC which calculates the positions of the satellites, controls functions of the communications transceiver and aims the antenna system in real-time. As the satellite pass proceeds the necessary Doppler (frequency adjustment) correction is made to the communications frequencies using an automatic frequency control circuit.
A plan is in progress to establish the methodology to receive and process terrestrial Ham Radio packet communications and perhaps upload these messages to the amateur radio satellites via remote means. Plans are being made to implement a Local Area Network (LAN) system so that Control Operators can remotely review files.
A high frequency (HF) transceiver has been recently added to the satellite station. The HF antenna is a vertical multiband antenna on the roof. The HF communications system permits the station operators to communicate with other Hams via more traditional methods on the long range amateur radio bands. The station operators have enjoyed showing the Amateur Radio Satellite Station Exhibit to people from all over the world.
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