preselector


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preselector

[¦prē·si′lek·tər]
(electricity)
Device in automatic switching which performs its selecting operation before seizing an idle trunk.
(electronics)
A tuned radio-frequency amplifier stage used ahead of the frequency converter in a superheterodyne receiver to increase the selectivity and sensitivity of the receiver.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
However, never enter a planned altitude in the preselector just because you know it's coming.
Other spectrum analyzers would bypass the YIG preselector when doing work above 3.6 GHz or even 8 GHz, depending on the manufacturer.
The fluid transmission preselector gear change was a feature of Daimler."
For example, option 067 for Anritsu's MS2830A provides preselector bypass that supports 125-MHz wideband measurements to 43 GHz on an appropriately configured instrument.
The poster advertised the new Lanchester motor car with fluid transmission and preselector gear change.
The IF pan display shows all signals in the preselector pass band.
The system is intuitive, has GPSS, autotrim, voice alert automation and an integrated altitude preselector; and is equally at home in a Baron or single-engine Rockwell.
This general architecture places preselector filters as the first element in the tuner chain, followed by low gain (typically 10-15 dB), high-intercept preamplifiers, followed by an upconverting mixer, amplification and filtering at the first IF (nominally 22.5 GHz), a downconverting mixer and, finally, second IF amplification.
Honeywell says the KFD 840 can replace the KAS altitude preselector that goes with KFC-200/250 autopilots.
The new spectrum analyzer also features good channel flatness for all measurements due to a switched-filter preselector.