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Old February 20th 11, 03:53 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,951
Default No comment three antennas - duplex

On Sat, 19 Feb 2011 23:33:03 -0800 (PST), "Sal M. Onella"
wrote:

Big problem: maintaining phase
linearity.


I was on duty aboard the USS Holland (my job, heading up the standards
lab) when one of the submariners rousted me out of my rack to make a
measurement - the last one before the captain could go out to sea.

I tumbled down the ladder (sometime in the early AM) to find a group
of techs huddled around a meg-Ohmmeter in the main passageway just aft
of Sherwood forest.

Now I add that significant detail because, as you mention about
maintaining phase linearity, every time a sailor shimmied past the
group to go forward, his movement would peg the meter in one direction
or the other. The guys were trying to measure a gigohm load in the
nuclear reactor. The disturbance of the local electric field was
enough to drive the resistance bridge wild. Any movement in its
vicinity was enough to do that. There was barely enough patience
among that group to let anything settle.

The sub couldn't move until they got at least 1 Billion Ohms, and when
I asked what the problem was (I was the pro from Dover there to rescue
their butts or the captain would keelhaul them), they said they were
several magnitudes of order off - too little resistance.

I hunkered down over the instrument, waited a couple of minutes before
the static fields settled and the instrument calmed, and I measured AT
LEAST a gigohm. "So what's the problem?"

"We need a billion ohms before we can certify the reactor is ready to
get underway!"

I looked at my measurement - easily a billion ohms, 1 gigohm (I
thought there wasn't that much resistance between us and the moon, but
I wasn't going to make that observation with the XO hunkered down
watching this, and the Old Man staring over his shoulder.).

"No, No! A BILLION OHMS!" came their plea when I pointed out the
measurement.

"What do you think a billion is?" I asked.

"We looked it up in the dictionary and its a million million."

I stood up and looked forward to crawling back into my rack. "That is
the English definition for billion. What you want is the American
definition for a billion which is a thousand million."

73's
Richard Clark, KB7QHC