9 . 3 MPX SECTION

1.Through 300 ohm dummy antenna, connect FM signal generator to 300 ohm FM antenna terminals.

2.Connect multiplex signal generator to extemal modulation terminals of FM signal generator.

3.Connect oscilloscopehorizontal input to MPX signal pilot output and vertical input via probe to TP (No. 13) of circuit board.

sx-450

4.Set SX-450 dial indication to 98MHz and adjust FM signal generator for center of scale indi- cation on AM/FM meter.

5.With FM signal generator unmodulated, adjust VR1 so that lissajouspattern on oscilloscope becomesstationary as shown in Fig. 12.

6.With MPX signal generator modulation lkHz, L + R 67.5kHz deviation and pilot 7.5kHz deviation, adjust T4 for minimum distortion.

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Pioneer sx-450 manual MPX Section
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sx-450 specifications

The Pioneer SX-450 is a revered receiver that has left its mark on the audio world since its introduction in the mid-1970s. Recognized for its impressive performance and classic design, the SX-450 remains a favorite among vintage audio enthusiasts and collectors.

One of the standout features of the SX-450 is its power output. Capable of delivering 22 watts per channel into 8 ohms, it offers a warm, rich sound that appeals to audiophiles who appreciate the nuances in their music. The receiver is designed to accommodate a wide range of speakers, making it a versatile choice for different audio setups.

In terms of connectivity, the Pioneer SX-450 is fitted with multiple input options, including phonograph, tape, and auxiliary inputs. This allows users to connect a variety of sources, such as turntables, cassette decks, and CD players. This versatility makes it a suitable receiver for both modern and vintage audio gear, providing audiophiles the opportunity to enjoy their extensive music collections.

Tuning capabilities are another highlight of the SX-450. It features a built-in FM stereo tuner with a wide frequency response and excellent selectivity, ensuring that users can access their favorite radio stations with clarity and precision. The receiver's tuning is complemented by a well-illuminated dial and a tuning needle that allows for easy signal acquisition, enhancing the user experience.

The design of the SX-450 is classic and appealing, featuring a brushed aluminum faceplate that exudes vintage charm. The control knobs are large and intuitive, allowing for easy adjustments of volume and tone settings. The eye-catching dial lights emit a warm glow, inviting users to enjoy their listening experience even in low-light conditions.

The Pioneer SX-450 also incorporates advanced technologies for its time, including a low-noise transistor design that minimizes distortion for cleaner sound reproduction. Its discrete output stage architecture enhances audio fidelity, ensuring faithful reproduction of recordings.

Durability is another characteristic of the SX-450, built to withstand years of use while maintaining optimal performance. This longevity contributes to its status as a sought-after vintage receiver, coveted for its nostalgic value and superior audio quality.

Overall, the Pioneer SX-450 is more than just a receiver; it represents a period in audio history where quality and craftsmanship were paramount. Skilled engineering, classic style, and impressive sound make the SX-450 a timeless piece of audio equipment that continues to resonate with music lovers today.
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