O I G I T O R I V E R

S E G M € N T D R I V E R

M U ! T I P L E X E R

P R E S E T A E L € 5 - D I G I T

O E C I M A L C O U N T E R

2 2 - 8 l I r 1 6 R O M

G N D

Fig . 4 - 5 Blockdiagramof PD5009

I

I I

I

val. Pin no.? of PD5009 is the brightnessselector terminal. The time division pulse width is set to 8009s for H level input signals,and to 200ps for

Llevel signals,thereby varying the degree of FL tube brightness (by varying the segment lighting period). Note that since the pov.er indicator FL tube is driven by static drive, the degreeof bright- nessmay be varied by changingthe grid voltage.

The 5.12MHz crystal oscillator generatesthe basic signai used in the preparation of the time division pulse signal and the counter gate circuit

control signal.

Terminals S1 - S4 (pin nos.3 - 6) are used in designating reception mode. The 2 reception modesemployed in the SX-3800 (seeTable 1) are designatedby varying the combination of input levels (H and L). The 3 different IFs during FM mode are required in coping with IF offset in the IF ceramic filter stage, 53 and 54 being preset during FM mode according to the ceramic filter characteristics.

Although the SX-3800 FM stage quartz-lock system is capable of locking any frequency within the FM band, the L0kHz digit (digit in the second decimal place) in the FM frequency display will appearonly as 5 or 0.

The frequency display FL tube alsoincorporates the TUNING and SIGNAL indicators. And al- though the segments(anode) for these indicators are static driven by the corresponding drive cir-

cuits, the edd is driven according to the D3 time divisionpulsetiming, therebyplacingthe segments

o,wI n l l t t r -

o o M

*l-w

,,iw 8 C = L ( D l M )

- ' l ' * i * i i l l

t{-- tm3 +

F i g . 4 - 6 D 1 - D 5 t i m e d i v i s i o np u l s es i g n a l s

under dynamic drive. In addition, the AM and FIW indicators in the frequency display section are lit accordingto the Db timing, while the kHz and MHz indicatorsarelit accordineto the D1 timine.

MODE

s1

S2

s3

I

l F { M H z )

 

H

L

L

H

1 07 3

F M

H

L

H

L

1 0 . 7 0

 

H

L

H

H

't

 

0.67

A M

L

H

H

L

4 5 0 k H z

T a b l e1

I

I

I

t

I

r

il i

t

t

1 0

t

 

Page 9 Page 11
Page 10
Image 10
Pioneer SX-3800 manual Blockdiagramof PD5009, G 6 D 1 D 5 t i m e d i v i s i o np u l s es i g n a l s, Mode, B l e1
Page 9 Page 11

SX-3800 specifications

The Pioneer SX-3800 is a classic stereo receiver that emerged in the late 1970s, embodying the high-fidelity audio aspirations of its time. As part of Pioneer’s widely respected SX series, the SX-3800 is hailed for its exceptional sound quality, robust construction, and an array of features that cater to both audiophiles and casual listeners alike.

One of the SX-3800's standout characteristics is its power output. It delivers a solid 80 watts per channel into 8 ohms, making it capable of driving a variety of speaker systems with ease. This ensures a dynamic audio experience, with clear highs, rich midrange, and deep bass. The receiver also exhibits low total harmonic distortion (THD) ratings, which means the sound produced is clean and faithful to the original recording.

The SX-3800 is equipped with a high-quality AM/FM tuner, which is known for its excellent sensitivity and selectivity. Featuring a large analog dial, it allows users to effortlessly dial into their favorite stations while the signal strength meter helps in fine-tuning the reception. This tuner is complemented by Pioneer’s proprietary Auto-Seek tuning function, making it easier for users to find and lock onto stations.

In terms of connectivity, the SX-3800 comes with several inputs and outputs, including phono, tape, aux, and multiple speaker outputs, offering flexibility for various audio setups. Additionally, the built-in phono preamp ensures that vinyl lovers can connect their turntables with ease, preserving the rich detail and warmth that analog sources are known for.

Another technological highlight of the SX-3800 is its inclusion of a loudness control feature, which allows users to enhance the low and high frequencies at lower volume levels. This feature is particularly useful for late-night listening or in quieter environments where detail is essential but loudness is not an option.

With its solid construction, vintage aesthetics, and a beautiful wood finish, the Pioneer SX-3800 not only performs well but also adds a classic touch to any audio setup. Its blend of features, performance, and timeless design continues to make it a desirable component in the world of vintage audio equipment. Collectors and enthusiasts appreciate the SX-3800 not just for its sound quality but also for its enduring legacy in the rich history of audio technology.
Top Page Image Contents