This is called the desert megaphone mystery. Unidentified since at least
1985, because they didn't ask us. Please take a look and solve this mystery. Its at
My guess is it is a microwave "back to back" antenna, that aids in sending microwave signals from one tower to another. It seems a bit odd that it is rusty steel or iron, though! Does it have some sort of mechanism for precisely pointing it? Even just all thread driven into the rock, with flanges and nuts so the horns can be elevated and aimed a bit would be enough. It is possible some radio amateurs did it for a point-to-point communication link, and didn't apply for a permit because they knew they wouldn't get it.
Jon
Isn't that near "Area 51" ? That may be the answer. gary
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