79 lines
2.0 KiB
Plaintext
79 lines
2.0 KiB
Plaintext
WERE SCANNER MANUFACTURERS PRESSURED
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TO LIMIT FREQUENCY COVERAGE?
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by Bob Parnass, AJ9S
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The 406 - 420 MHz band has long been used by federal govern-
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ment agencies for communication of sensitive information.
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Until just a few years ago, this range was not receivable on
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programmable scanners sold by Electra (Bearcat), Regency, or
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Radio Shack.
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Speaking at a scanner club meeting in Berkeley, Illinois, an
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engineer from Electra confirmed the rumor that it was US
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government pressure which persuaded scanner manufacturers,
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eager for timely FCC Part 15 certification, to omit this
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band from their models.
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Tradition was broken in 1982 when Radio Shack imported the
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2020 scanner, made by General Research Electronics of Tokyo,
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which featured coverage down to 410 MHz. Sales literature
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for JIL's imported SX200 even went so far as to openly tell
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customers that they could "Tune Military, FBI, ...., DEA,
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Defense Department, Justice Department, plus other res-
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tricted radio bands no other scanner is programmed to pick
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up."
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Not to be outdone by the imports, Electra introduced its
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American made Bearcat 200 with coverage to 406 MHz.
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Regency, whose American scanners were spec'd down to only
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440 MHz, made service manuals available which revealed cov-
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erage below 440 MHz was possible on all its programmables by
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simply striking the "." key before entering the frequency
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digits.
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Today, government agencies are using digital voice scram-
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bling and spread spectrum techniques to ensure privacy of
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sensitive communications.
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--
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============================================================================
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Bob Parnass, AJ9S - AT&T Bell Laboratories - att!ihuxz!parnass (708)979-54 |