Difference between revisions of "Radio Crystal Identification"
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Crystals must be custom tuned by cutting or grinding to exact dimensions and tolerances to achieve a highly accurate desired frequency. | Crystals must be custom tuned by cutting or grinding to exact dimensions and tolerances to achieve a highly accurate desired frequency. | ||
+ | Crystals age over time and cause the frequency to drift from the original design. | ||
+ | Because a crystal can operate at either its series or parallel resonance frequencies a crystal oscillator circuit needs to be tuned to one or the other frequency as you cannot use both together. | ||
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+ | A quartz crystal can act as either a capacitor, an inductor, a series resonance circuit or as a parallel resonance circuit. | ||
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+ | ==identification== | ||
Crystals marked P-77 are for radio shack scanner with 10.7 IF | Crystals marked P-77 are for radio shack scanner with 10.7 IF | ||
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==references== | ==references== | ||
* [http://www.kenselectronics.com/lists/scantype.html Police Scanner Crystal Interchangeability Information Reference from Ken's Electronics] | * [http://www.kenselectronics.com/lists/scantype.html Police Scanner Crystal Interchangeability Information Reference from Ken's Electronics] | ||
+ | * [http://www.electronics-tutorials.ws/oscillator/crystal.html Quartz Crystal Oscillators] |
Latest revision as of 14:06, 2 August 2017
In the radio world we use the quartz crystal to construct a crystal oscillator. The vibrating crystal generates a sinusoidal electronic signal on a precise frequency.
The modern radio receiver uses a 10 MHz quartz crystal as a reference for the frequency synthesizer for the tuned frequency.
Crystals must be custom tuned by cutting or grinding to exact dimensions and tolerances to achieve a highly accurate desired frequency.
Crystals age over time and cause the frequency to drift from the original design.
Because a crystal can operate at either its series or parallel resonance frequencies a crystal oscillator circuit needs to be tuned to one or the other frequency as you cannot use both together.
A quartz crystal can act as either a capacitor, an inductor, a series resonance circuit or as a parallel resonance circuit.
identification
Crystals marked P-77 are for radio shack scanner with 10.7 IF