OSACR
Amateur Satellites

Well, it is a beautiful day in the woods far from any cell phone tower.  Our camp is setup now and it is time to call home.  The antenna is packed, rolled up neatly in its own bag.  I unroll the bag revealing all of its parts tucked in various pockets.  In about 6 minutes, the antenna is put together and ready to be connected to the radio.  The heaviest thing in my backpack is a 12 volt nickel metal hydride battery.  This too is connected to the radio and the rig is turned on.

The radio is an ICOM W32A duel band portable transceiver.  The target today is a space satellite called AO-27.  This satellite receives on 145.850 MHz and transmits on 436.800 MHz FM.

If one person on one part of the planet in line of site of the satellite was transmitting, another person on another part of the planet in line of site of the satellite was receiving; they could talk to each other.

The antenna being used here is a narrow beam dual band antenna which is held pointing directly at the place in the sky where we hope the satellite is.   It is difficult to hear the transmitter of this satellite because it transmits with only about 8/10^th of a watt of power.

There are other satellites one could talk in on.  Also, with approval, one could talk to the International Space Station.  These satellites and the space station are described at the AMSAT web site Satellite Schedules.

The amateur radio satellites are called OSCARs or Orbiting Satellites Carrying Amateur Radio.  These series of small satellites were initiated for radio amateurs to experience satellite tracking and participate in radio propagation experiments. Transmitting low-powered signals, these satellites have become increasingly sophisticated. More recently, they have served many school science groups, provided emergency communications for disaster relief, acted as technology demonstrators, and sent back pictures of the Earth.

The first amateur radio satellite was launched in December of 1961 from Vandenberg Air Force Base in California.  The OSCAR One Satellite, as it was called, was launched along with a United States Air Force satellite.

A group of amateurs in California formed a project called OSCAR and persuaded the United States Air Force to replace ballast on the upper stage of the payload with the OSCAR One package. This satellite was a box shaped cube with a single rod antenna.  It had no solar power capabilities, rather it was battery powered.  After the OSCAR One Satellite was set in orbit, the low power transmitter transmitted a morse code signal (hi-hi) on the VHF 145 MHz 2 meter band for three weeks until it discharged its batteries. Over 500 Amateurs in 28 countries reported receiving the simple morse code. The OSCAR One satellite re-entered the atmosphere in January of 1962 after 312 revolutions.

KC8OUW 2011