Meteors are small particles of matter, most only the size of a grain of sand. When the earth's orbit crosses a large volume of meteors, we have a "shower". Most of the time, however, we pass through space being pelted by "random" meteors. The average daily number of random meteors entering the atmosphere is 12 billion. It is this type meteor that we primarily make use of in the HSCW mode.
Meteors burn up in the atmosphere at about the same height as what we know as the E-layer of the ionosphere. This makes the HSCW DX range for contacts about the same as what we have come to expect from traditional E-skip. A radio signal reflected by a typical random meteor will be very short, normally too short to sustain voice contact. The HSCW mode brings about a much higher rate of success with DX contacts because of it's effeciency.
The key to HSCW is:
1. Have the ability to transmit Morse Code at a high rate. This enables QSO data to be communicated even with very short reflection times.
2. Have the ability to receive and record the incoming high speed CW signal. The record function can be performed in several ways and is necessary so that the data can be reviewed.
3. Have the ability to de-code the Morse Code either audibly or visually. The primary method used is to slow down the audible signal to a speed which the operator can de-code. Another method uses a spectral computer display which can be adjusted to show the dots and dashes contained in the data. The operator then forms the code mentally.
HSCW is not new. Early Meteor Scatter experiments were made in the U.S. using C.W. speeds high enough to require tape recording of the received signals. The Europeans have been using HSCW for about 20 years!
Currently activity is centered on 144Mhz and 50Mhz. A number of stations are getting geared up on other bands as well.
HSCW is challenging and rewarding. Why not give it a try?
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