Hi gang, here are some OMEGA basics:
- world-wide navigation system, accurate to +/- 10 nautical miles.
- based on VLF transmissions between 10 and 14 KILOHERTZ.
- about 9 stations provided world-wide coverage 24 hours a day.
- all stations phase-synchronized with atomic clocks (even 20 plus years ago).
- receiving stations measured phase difference between received signals
and extrapolated position from this.
- the Hawaii station was operated by the US Coast Guard and closed down
about 3 years ago. Don't know if the system is up at all (world-wide).
- the Hawaii station used an 800 foot base-fed vertical suspended from
2500 foot long horizontal wires strung across the mountain peaks of Haiku
valley at Kaneohe, Oahu. the horizontal wires provided some top-loading
but were not radiators as such.
- radials consisted of one EVERY DEGREE, as long as possible (from the
transmitter building to the edges of the valley's upward cliffs several
hundred feet away), and were supposed to be 1" diameter copper originally.
- as I recall the power input to the final amplifier was something like a
megawatt, but even 800 feet is pretty short at 10 KHZ (hi hi) so efficiency
was quite low.
- I went through the Haiku faculity twice some years ago, but I'm sure
that Lee KH6BZF can correct my errors and omissions, having lived in the
Kaneohe area for many years hi Lee go ahead and straighten me out hi hi.
73, Warren KH6WM
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