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RE: Sputnik I launched Oct. 4 1957

Here is an AMSAT web page with recordings of the first satellites including Sputnik.
Hope this posts all ok.

73, Roy -- W0SL

                [logo100.gif] Sounds from the First Satellites

   Roy Welch, W0SL, has provided these historical audio recordings of
   several "first" satellites as monitored at his station (then W5SLL).


   Oscar 1 was launched on an Agena B rocket from Vandenberg AFB in
   California along with a Discoverer series satellite. KC4USA in
   Antarctica first reported signals as it passed over there after being
   launched. Oscar 1 was battery powered. Its signals lasted for about
   two weeks. The batteries were not rechargeable. The transmissions were
   on 145.00 MHz. The CW signal repeatedly sent HI in morse code. The
   number of HIs per minute, or the "HI Rate" was the only telemetry
   sent. The HI Rate gave the internal package temperature. Amateurs were
   asked to report the HI rate.

   At W5SLL, there was no tracking antenna available. The antenna was cut
   for 108 MHz for listening to the new USA satellites. It was a six
   element colinear array constructed on a 13 by 13 foot wooden frame and
   suspended above a "chicken wire" reflector. The whole array was placed
   on the roof of the house looking up at about 75 degrees above the
   southern horizon. Satellites were captured as they flew through the
   main lobe of the antenna.

   Listen to the normal speed recording (.WAV (113K) or RealAudio (14K)).
   Each HI is too fast to make out, and sounds more like a cricket
   chirping. Now listen to the half speed recording (.WAV (226K) or
   RealAudio (21K)), or if all that noise hurts your ears, listen to this
   filtered version (.WAV (226K) or RealAudio (21K)). You can distinctly
   read the HIs being sent. This recording was made in Dallas, Texas on
   December 14, 1961, at 0722Z using a Tecraft converter in front of a
   National NC-300 receiver.

   See also this newspaper article (120K GIF) on OSCAR 1.


   Sputnik 1 was the Soviet Union's and the world's first orbiting
   satellite. The signals heard in this recording are weak, over the
   horizon signals, recorded on a frequency of 20.007 MHz. Other
   recordings were made with signals strong enough to permit hearing the
   oscillator feeding through during key up periods. These were made with
   the satellite in line of sight. The weaker signal recording is
   presented to show a time when the keying of the signal was interrupted
   and a steady carrier was transmitted. There are two such instances in
   this excerpt. WWV which was nearby in frequency shut down their
   transmitters with each pass on this evening.

   Roy and his three-year-old daughter would put the radio speaker in a
   window and then go outside and listen to the strong signals while they
   watched the third stage booster tumbling end over end like a bright
   pulsating star as it passed over in the evening sky. Listen with them
   to this recording of Sputnik 1 (.WAV (113K) or RealAudio (10K)). This
   recording was made in Dallas, Texas on October 7, 1957 at 0457Z using
   a military surplus AN/FRR3A HF RTTY receiver.

   Here is a strong signal from Sputnik 1 (.WAV (116K) or RealAudio

   Here is a newspaper photograph (234K GIF) of Roy playing Sputnik
   signals at the State Fair of Texas on October 9, 1957.

Explorer 1

   Explorer 1 was America's first orbiting satellite, launched on an Army
   Redstone rocket after several failures to launch the Vanguard
   Satellite with the Navy's Vanguard rocket. The telemetry heard in this
   recording consists of a combination of three or more relatively stable
   audio tones and two alternating audio tones. The alternating tones
   were indications of cosmic particle collisions detected by an on board
   counter. The tones shift from one to the other when the detector has
   counted sixteen particles. It shifts back again with the detection of
   the next sixteen particles and so on.

   The satellite had two RF frequencies, 108.0 MHz and 108.03 MHz. This
   recording is from the 108.0 MHz frequency. The 108.03 MHz frequency
   had a similar sounding telemetry, but without the alternating tones.

   Listen to the recording of Explorer 1 (.WAV (110K) or RealAudio
   (10K)). This recording was made in Dallas, Texas on February 11, 1958
   at 0100Z using a home-made VHF converter in front of a National NC-300
   receiver. The antenna was as described above for Oscar 1.


   These single sideband transmissions were from KP4BPZ in Arecibo,
   Puerto Rico via Moon Bounce. The KP4BPZ transmitter was running about
   500 watts on 432 MHz and feeding the 1000 foot diameter radio
   telescope dish in Arecibo. Amateur radio operations were made on the
   two week ends of July 3, 1965 and July 24, 1965. Both SSB and CW
   operations were heard.

   The receiving setup at W5SLL/0 was assembled quickly after the plans
   were announced. The antenna was a home made 32 element colinear array
   from the ARRL Antenna Handbook design. The individual small booms were
   completed, but they were not mounted on a metal frame. A 2X4 wooden
   frame was hastily built and holes drilled to accept the 16 individual
   element booms. The transmission feedline was 75 feet of plain old 300
   ohm TV twinlead, terminating in a coax 4:1 balun.

   The output of the balun fed the input of a homemade 432 MHz converter
   described in the July 1963 QST magazine article, "All Nuvistor
   Converter." The Nuvistor was a small vacuum tube, for those of you who
   don't remember the Nuvistors. The noise figure was not worth
   mentioning in view of today's technology. The output of the converter
   fed the input of a National NC-300 Amateur Band receiver.

   The antenna was aimed by leaning the wooden frame against a kitchen
   chair in the back yard and eyeballing it toward the crescent moon in
   broad daylight. Not exactly an ideal Oscar 0 station. What a signal!
   Just imagine what it would sound like today with our low noise preamps
   in front of our high performance converters and radios with steerable
   circular polarized antennas.

   Listen to the EME signals (.WAV (150K) or RealAudio (14K)). This
   recording was made in Florissant, Missouri on Saturday, July 3, 1965.

Vanguard 1

   Vanguard 1 was launched aboard the oft-troubled Vanguard rocket in
   March 1958. The transmitters were approximately 10 mW in power and
   transmitted on 108.0 MHz and 108.3 MHz. The only telemetry transmitted
   was the package temperature. This was indicated by the difference
   between the two transmitter frequencies which varied with temperature.
   The solar cells were manufactured by Bell Laboratories.

   The signals were received on a homemade VHF converter in front of a
   National NC-300 Amateur Band receiver. The signals were continuous
   carrier with no apparent audio modulation. Therefore, the recordings
   were made with the receiver Beat Frequency Oscillator (BFO) turned on
   in order to produce an audible tone heard in the recordings.

   Listen to these two recordings. In this recording made shortly after
   launch (.WAV (115K) or RealAudio (11K)) you can detect a rapid spin
   modulation on the signal and can determine that the satellite seemed
   to be spinning fairly rapidly. In this recording made approximately
   one year after launch (.WAV (115K) or RealAudio (11K)) you can tell
   the satellite is turning very slowly. By this time the batteries had
   failed and the satellite was powered only by the few solar cells on
   the surface of the satellite. The satellite was very small, not much
   larger than a large grapefruit, so there wasn't room for many solar
   cells. The transmitter frequency varies as the solar cells slowly turn
   into and out of the sunlight.

   Sometimes the signal would disappear when no solar cells were exposed
   to the sun. It was easy to determine when Vanguard 1 went into the
   shadow of the earth, by the rapid change in frequency and abrupt loss
   of the signal altogether. This is not demonstrated in this recording.


   OSCAR 10 was the first Phase 3 OSCAR to reach orbit. This SSB
   recording from OSCAR 10 (.WAV (113K) or RealAudio (10K)) demonstrates
   the long propagation delay experienced with high orbits.

   Updated 15 December, 1996. Feedback to KB5MU. The RealAudio sounds on
   this page are encoded in the 14.4kbps mode, but you can listen to them
   over any speed link, since they are being sent to you as files and not
   as RealAudio streams. The RealAudio Player is available for free from

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