Clarion DRX9255 Kullanıcı El Kitabı - Sayfa 16

Araba Stereo Sistemi Clarion DRX9255 için çevrimiçi göz atın veya pdf Kullanıcı El Kitabı indirin. Clarion DRX9255 19 sayfaları. Am/fm stereo cd player with cd changer control
Ayrıca Clarion DRX9255 için: Kullanıcı El Kitabı (20 sayfalar), Kullanıcı El Kitabı (19 sayfalar)

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7. FM RECEPTION

mnGiTUNEia® tuner

Understanding the Difficulties of

FM Reception in Your Car

FM radio waves are transmitted in the very high

frequency range (VHF). These waves move in

straight lines, much like light. Tall buildings, hills

and mountains, or other obstructions may cause

"shadows" or loss of signal, noted by a momen¬

tary "hissing" noise in the reception.

These obstructions found in day-to-day urban

travel can reflect or bounce the signal. When

reflected and direct signals arrive at the radio's

antenna together, a similar noise problem may

occur, called multi-path interference.

In addition, the vehicle itself can be the culprit,

creating various types of impulse noise (usually

associated with the vehicle's ignition and/or

other parts of the electrical system), which again

will deteriorate signal quality.

The

mflGITUNEH®

AM/FM Tuner

IffiGl'TUNEQ®

combines both AM and FM

tuners into one small, unique package. The

design incorporates many advanced technolo¬

gies exclusively engineered to improve FM and

AM performance.

Signal Actuated Stereo Control

(SASC)

In weak signal conditions, the SASC circuit will

provide optimum, low noise reception. As the

signal weakens, stereo separation is smoothly

converted to a monaural signal with a gradual

"cut-back" on high frequency reproduction, mini¬

mizing "hiss" and noise.

FM Impulse Noise Canceller (Clean

Z1)

To deal with radiated RF energy noise (usually

caused by the vehicle's ignition system), Clarion

devised the Clean Z1 - a circuit that attacks

impulse noise at its source. It is not to be con¬

fused with a simple series filter. Instead it is a

highly discriminating circuit that identifies and

eliminates noise components in an FM source

while still preserving the overall integrity of the

signal.

Balanced Mixer FM Front-End -

Dual-Gate FET

The balanced mixer pre-amp section is designed

to provide a uniform signal to the tuner - creat¬

ing the best possible noise-free reception. A

variable gain stage automatically controls the

amplitude of the signal according to the incom¬

ing signal strength. As the signal deteriorates or

weakens, the gain is "increased" to ensure the

highest quality signal with the least amount of

noise. When signal strength becomes very

strong, the gain is reduced, avoiding unneces¬

sary distortion.

Triple Stage Narrow Band IF Filters

The new triple stage IF and ceramic filter system

enables the tuner to "focus" on the selected fre¬

quency - ignoring stronger or nearer stations to

prevent frequency "hopping". With this type of

narrow band filtering, the selectivity of the tuner

can be increased.

Six Diode 1C in the AM Section

Typically, in the design stage of most tuners, the

AM section receives the least emphasis.

However, Clarion realizes the importance of the

AM tuner. Our use of a new 6-diode 1C greatly

enhances AM performance by reducing distor¬

tion and improving the overall sensitivity of the

tuner.