Wednesday, December 28, 2011

R7000 History

After my move in November 1994, it took over a year before I put up any antennas -- I was much too busy with young kids, new job, finishing the basement, etc. In January 1996, I put up a 125 foot doublet up about 15 feet and operated the NAQP CW contest. That doublet got mounted higher by the NAQP phone, and was joined with some attic antennas.

By the fall of 1996, I was in the market for an antenna that could reasonably support several bands, including the WARC bands. The R7000 seemed like a pretty nice solution -- seven bands with an option to  add 80m as well. I bought one in November of 1996.

To mount it, I joined a 10 foot piece of 1 1/2 inch rigid EMT to a 12 inch steel pipe nipple and planted it 3 feet in the ground using two sacks of concrete. The pipe union was buried in the concrete. The resulting vertical pipe was about 1.9 inches in diameter -- almost large enough to fit the mounting U-bolts -- and nearly 8 feet tall.

While not as optimal as the specified 2 inch mast, this support worked very well for 15 years. I only stopped using the R7000 a couple of years ago when the coax to it was cut when the cable company re-buried the cable. (That one was cut by septic tank workers repairing the system)

The R7000 was not a great performer, in my opinion. I first called it the R7000 attenuator. I later discovered that it was designed to work at a height of 18 feet, not the 8 feet I had installed it. After a few years, I got the idea to add some radials at the base of the mast. Seven 20-foot radials made the antenna appear to work a lot more reasonably.

Since I wasn't using it at the old QTH, the R7000 seemed like the perfect antenna to move to the Micro-Shack. It required only one support, covered seven bands, and with a few radials seemed to work OK. A mediocre antenna seemed better than none at all.

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