CD-C621H (serv.man19). Adjustments - Sharp Audio Service Manual (repair manual)

– 10 –

•

Play: TW-2412

Tape 1: Over 80 g
Tape 2: Over 80 g

•

Play: TW-2111

30 to 60 g. cm

30 to 60 g.cm

Fast forward: TW-2231

—

60 to 120 g.cm

Rewind: TW-2231

—

60 to 120 g.cm

•

Normal

MTT-111

VRM1

3,000 

±

Speaker

speed

30 Hz

terminal

fL: Low-range frequency
fH: High-renge frequency

• 

Signal generator: 400 Hz, 30%, AM modulated

IF

450 kHz

1,620 kHz

T351

*1

MW Band

—

522 kHz

(fL): T306

*2

Coverage

1.1 

±

 0.1 V

MW

990 kHz

990 kHz

(fL): T302

*1

Tracking

*1. Input: Antenna,

Output: TP302

*2. Input: Antenna,

Output: TP301

•  FM
Notes:
1: Description of the "FM IF Adjustment" is not carried on this

Manual. It is because the IF coil in the FM front end section
has been best adjusted in the factory so that its further
adjustment is not needed at the field. When replacing the
FM front end assembly, no adjustment is needed either.

2: The parts in the FM front end section are prepared in a

complete unit, so you can't obtain each part individually

•  FM Mute Level
Signal generator: 1 kHz, 40 kHz dev., FM modulated

98.00 MHz

98.00 MHz

VR351

Input: Antenna

(25 dB

µ

V)

Output: Speaker
Terminal

VRM1

TAPE
SPEED

FAS
SW

SWM1

TAPE MECHANISM PWB

TP302

R357

L354

T351

VR351

FM MUTE
LEVEL

R336

TP301

FE301

T306

T302

L341

SO301
FM ANTENNA
TERMINAL

CNP301
MW LOOP
ANTENNA
TERMINAL

TUNER PWB

CNP303

AM IF

MW BAND
COVERAGE

MW
TRACKING

– 11 –

Since this CD system incorporates the following automatic adjustment function, when the pickup is replaced, it is not necessary
to readjust it.
Since this CD unit does not need adjustment, the combination of PWB and laser pickup unit is not restricted.

• Automatic adjustment item
1. Focus offset (Fig. 11-2)
2. Tracking offset (Fig. 11-3)
3. E/F balance (tracking error balance) (Fig. 11-4)
4. RF level AGC function (HF level: constant)
5. RF level automatic follow-up of the tracking gain

This automatic adjustment is performed each time a disc is changed. Therefore,
 each disc is played back using the optimal settings.

Only in STOP state it is possible to slide the pickup with the (

) or (

) key.

VOL. --- Last memory
BAL. --- CENTER
R.GEQ. --- FLAT
X-BAS --- OFF

Canceling method -  POWER OFF

• Setting the test mode
Any one of test mode can be set by pressing several keys as follows.
<REC. PAUSE> + <DISC. SKIP> + <POWER>     TEST: CD operation test
• TEST mode
Function — CD test mode

Setting of TEST mode

Indication of CD TST mode (Fig. 11-1)

OPEN/CLOSE operation is manual operation.

The pickup can be moved by using the (

) or (

) key.

<MEMORY>
LASER ON

<PLAY> key input

Press <STOP> key.

Stop

TOC. IL is performed, and the ordinary PLAY is performed.
If the following key is pressed during PLAY, it is possible
to specify directly any Track No.
<Disc Number 1> key: Track 4
<Disc Number 2> key: Track 9
<Disc Number 3> key: Track 15

<MEMORY>
Tracking on the spot.
SERVO OFF PLAY

<MEMORY>

Tracking on the spot.
SERVO ON PLAY

STOP

IL is not performed.

<STOP>

2

 0.1s
0.50 V
IC1  20   FE

 0.1s
0.50 V
IC1   7   TE

1

 FOCUS
OFF-SET
ADJUST

 TRACKING
OFF-SET
ADJUST

2

1

10ms
0.50 V
IC1  20   FE

10ms
0.50 V
IC1  7   TE

Enlarged
View

TRACKING
OFF-SET
ADJUST

2

1

TO

TE

200 ms
1V/diV
IC 1   15

200 ms
1V/diV
IC 1    7

TRACKING/
ERROR
BARANCE
ADJUST

– 12 –

No

Hold down the 

ASPM button for 3 more second.

“ASPM” blinks in the display

.

Preset CH memory full over?

No operate. 

After displayed “END”. Return to

previous station.

SD (TUNE) DET out OK?

If count 1st OK?

If count 2nd OK?

RDS signal or not?   PI—identify

Comparing PI cord same or not?

between current receiving PI and

before PI which is already memorized

by 

ASPM on this time.

Comparing freg. same or not?

between current receiving frequency

and (already) previously memorized

frequency

.

Memorized to the lowest

vacant preset channel.

Preset CH memory become full over?

Begin to 

ASPM SCAN from the next

CH-SP

AN again.

Repeat and continue with same format

ASPM operation untill 108 MHz.

After reached 108 MHz, displayed the

TTL quantity of memorized stations.

And return to the previous receiving

freq. automatically

.

Displayed the 

TTL

 quantity of memo-

rized stations by 

ASPM operation on

this time. 

And return to the previous

receiving freq. automatically

.

Ye

s

No

Ye

s

Ye

s

Ye

s

Ye

s

No

No

No

No

No

No

Ef

fect

Pass

No ef

fect

Pass

No ef

fect

Pass

No ef

fect

Pass

No ef

fect

Ye

s

No

Ye

s

Compare the field strength of current

receiving signal. Is receiving signal

stronger than signal which has same PI

cord and is already memorized to

preset memory ahead of this receiving

time?

Ye

s

No ef

fect

No

No ef

fect

Comparing freg. same or not?

Between current receiving frequency

and (already) previously memorized

frequency

.

Ye

s

Memorized to the lowest

vacant preset channel.

Ye

s

No ef

fect

Begin to scan start 87.50 

→ 

108.00 MHz

– 13 –

4. No adjust type (None adjusting circuit.)
5. Added EON button.
6. Need to change RDS logo due to add EON feature.
7. Added EON—TI, EON—PTY function.

EON—PTY: Select and set the desired “PTY” 

→ 

stand-by 

→ 

switch to ON (other network) Station at the start of desired PTY

automatically 

→ 

stay and listen to PTY of ON station 

→ 

switch back to TN (This net) station automatically at the end

of PTY (ON) i.e. after changing to another PTY (except AF M FAIRS) or cancelling to receive PTY of ON station
midway.

EON—TI:

Select and set the “TI” 

→ 

stand-by 

→ 

switch to ON station at the start of traffic announcement automati cally 

→ 

stay

and listen to TA of ON station 

→ 

switch back to TN station autmatically at the end of TA (ON).

ie after TA (ON) is over or cancelled to receive TA of ON station midway.
When switching TN 

→ 

ON station.

In case of exist 2 more stations having the desired (specified) “PTY” or “TI”, the receiver will select and switch to ON station
comparing field strength at the same time. But when the frequency of ON station exists in the preset-memory, then reciver
switches straight to that ON station (CH), without comparing field strength so can make a quick switching from TN—ON station.
Preset memory takes priority of switching TN—ON station.
Therefore ASPM is usefull not only for PTY search but also for rapid EON switching.
Anyway CD-C621H EON is basically stand-by and receiving method, along with the Guidelines for EON implementation.

• ASPM SCAN: 87.50MHz 

→

 108.00 MHz.

• Only RDS signal is memorized by ASPM because RDS signal has PI code and is suitable and convenient for ASPM operation.
  ASPM
  Comparing field strength, only one strongest RDS station is memorized of all stations (repeater relay stations)  that have same

PI code.

Same PI code —  freq: different

   (AF’S)

      PS: same
      PTY: same

Each PI has AF’S list by individually.
Exa: P1 has f

1

, f

2

, f

3

 (same PTY).

        P2 has f

4

, f

5

 (same PTY).

Pickup and memorized to preset CH.

f 1
f 2

f 3

P 1 (PI cord)
PS 1 (Station Name)

f 5

f 4

P 2
PS 2

     f 6
f 7

f 8

P 3
PS 3

f 9

f 10

f 11  f 12  f13

P 4
PS 4

  Select signals (f1, f5, f7, f10) are memorized in the preset memory by ASPM.
• If tentative - ASPM operation is repeated intententionally, never memorized (over write) at the same frequecy.

1st time ASPM 

→ 

strongest stations of each pi are memorized.

ASPM is not only very usefull for PTY search, but also EON operation.
2nd time ASPM 

→

 2nd strong stations of each pi are memorized and so on.

PTY search function is equal to FM band search function as a result.

CD-C621H RDS function is equal to adding EON feature to the current CD-C75H RDS.
EON feature is EON—PTY and EON—TI.
Although PTY and TI indicators are separated, PTY contains TI in the PTY items (software) like current PTY search items.

NEWS,

AFFAIRS,

INFO,

ALARM,

TI

(TTL 17 kinds)

EON—PTY

EON—TI

Can select and stand-by

Can select and stand-by

EON—PTY and EON—TI are basically stand-by 

→

 receive the desired program of ON station.

1. PTY item: added TA.TTL 18 kind.
2. Each “TP”, “TA” ind. light up or go out individually.
    “TA” ind. doesn’t light up on current model, CD-C75H due to none EON—TI.
3. Added 3 indicators(in FL) due to adding EON feature.
    EON: Lights up only during receiving EON data (14A).
    TI:

During EON-TI stand-by 

→

 Light up

During receiving ON station. 

→

 blink.

    PTY: During EON-PTY stanb-by 

→

 Light up

During receiving ON station. 

→

 blink.

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