Pioneer SX-4L Посібник з експлуатації - Сторінка 13

Переглянути онлайн або завантажити pdf Посібник з експлуатації для Приймач Pioneer SX-4L. Pioneer SX-4L 15 сторінок. Computer controlled stereo receiver

Друкувати сторінку

4. Loudness as determined by a twin T-shaped

filter connected between pin 3 (6) and pin 5

(14) is activated when the LOUD terminal

(pin 7) is switched to L level.

The operation command input key matrix for

the VOLUME control is outlined in Fig. 1-7.

Key description

VOLUME UP, DOWN : Increase and decrease of

5-bit electronic volume control

data

(*11). 32 positions are available (00 to

3 1 ) .

MUTING : Audio muting switch (*12).

VOLUME PRESET : Memory switch for the elec-

tronic volume control steps positions

(32 positions from 00 to 31).

MEMORY/STOP

: Memory store enable key. A

single push enables VOLUME position

and STATION frequency to be stored

in memory during a 5 second period.

(*11)

The S-bit output data from Oa - OZ and Rgpins is

conuerted f'rom digital to analog data by ladder

resistor and applied to pin 12 of PA5004.

(*12)

The Rg pin is switched alternately to H and L leuels

each time this switch is pressed. This H/L leuel is

applied to pin 11 of PA50O4, the L leuel resulting in

actiuation of the muting circuit.

o Other Terminals

Switched to L level when the electronic

volume control position (00 - 31) is display-

ed. The VOLUME indicator is controlled by

this signal (SX-? and SX-6).

Switched to L level when the VOLUME

PRESET key is pressed once, and when the

MEMORY/STOP key is pressed, L level and

H level are switched alternately for a 5

second period. The PRESET STEP indicator

is controlled by this signal.

Switched to L and H level alternately each

time the MUTING

key is pressed. The

PA5004 audio muting operation (-25dB)

and the MUTING indicator are both con-

trolled by this signal.

Switched to L level during time display by

PD6007. The colon (:) in the time display is

controlled by this signal (SX-7).

And with the PD6004, this pin is switched

to L and H levels alternately during frequen-

cy scanning operations, the signal being used

to turn the TUNED indicator on and off

(Sx-5 and SX-4).

: Switched to

L level when 50kHz unit

included in the FM tuning frequency (during

tuning mode where FM frequencies are

changed in 50kHz steps). This signal controls

the "0" and "5" in the 5th digit position

(10kHz unit) in the FM frequency display.

And with the PD6004, this pin is switched

to L level when the LW band is selected (in

models equipped with

2-band AM tuner

section).

: Synthesizer IC (M54922P) control output

(data transfer clock I). Data transfer is

commenced by the trailing edge of this

signal (i.e. the moment that the pin is

switched to L level).

: Synthesizer IC (M54922P) control output

(data transfer clock II). Data reading timing

signal. The M54922P reads data by synchro-

nizing with the trailing edge of this signal.

R8, R9, R10, R11 : Data output and key inputs

applied toM54922P.

RL2 : Muting output. Switched to L level for

about 1 second when PHONO, AUX, FM

and AM (LW/MW) key is pressed. Also

switched to L level (for about 0.7 seconds)

when the Ml

M8, TUNING

UP or

TUNING

DOWN key is pressed. These

signals control the electronic switching IC

(PA4008) in order to suppress switching

noise.

Rl-3 : Scanning operation stopped when an H level

input signal is applied during STATION

SCAN or STATION SEARCH tuning mode.

Input of detector signal from tuner section

tuning detector circuit.

Memory Hold

Model SX-7 is equipped with an auxiliary power

supply circuit used to supply the microcomputer

with power irrespective of the POWER switch

position. In this way, the microcomputer RWM

(read write memory) contents can be preserved

for about 2 weeks when the AC mains power is

completely switched off. The clock function is

inhibited in this case. If the AC mains power is

left off for more lhan 2 weeks, the RWM contents

will disappear, and will therefore have to be

rewritten if the memory is to be used again.

The RWM hold period in the SX-6, SX-5 and

SX-4 models when the POWER switch is left off

is about 3 days. When two new size "AA"

dry

batteries are used, however, memory contents can

be maintained for several vears.

R 2