VC-MH73HM. Supplement Service Manual (base model - VCMH721HM) - Sharp VCR Service Manual (repair manual)

1

VC-MH73HM

VC-MH730HM

In the interests of user-safety (Required by safety regula-
tions in some countries) the set should be restored to its
original condition and only parts identical to those speci-
fied be used.

Page

SPECIFICATIONS ....................................................................................................................... 3
ROM MAP .................................................................................................................................... 4
CIRCUIT DIAGRAMS .................................................................................................................. 5
REPLACEMENT PARTS LIST ..................................................................................................... 6
PACKING OF THE SET ............................................................................................................... 8

This service manual covers only those items that differ
from the VC-MH721HM.  For further information on items
not covered by this supplement refer to the Service Manual
for VC-MH721HM.

2

VC-MH73HM
VC-MH730HM

When servicing the unit with power on, be careful of the section marked with white around it.
This is the primary power circuit which is live.
When checking the soldering side in the tape travel mode, make sure first that the tape has been loaded and
then turn over the PWB with due care to the primary power circuit.
Make readjustment, if needed after replacement of part, with the mechanism and its PWB in position in the main
frame.

Insert the sensor’s projection deep into the upper hole of the holder. Referring to the PWB, fix the sensors
tight enough.

Refer to the symbol on the PWB and the anode marking of the part.

Adjust the notch of the part to the white marker of the symbol on the PWB. Do not allow any looseness.

Be careful not to confuse the setting direction of the parts in reference to the symbols on the PWB. Do not
allow any losseness.

3

VC-MH73HM

VC-MH730HM

Format: VHS PAL standard

Video recording system: Two rotary heads, helical scan system

Video signal: PAL colour and I signals, 625 lines

Recording/playing time: 240 min max. with an E-240 tape (SP)

480 min max. with an E-240 tape (LP)

Tape width: 12.7mm

Tape speed: 23.39 mm/s (PAL/SP)

11.70 mm/s (PAL/LP)

Antenna: 75 ohm unbalanced

Receiving channel: UHF Channel E21-E69

RF converter output signal: UHF Channel E21-E69 (Preset to CH E36)

Power requirement: AC230V-240V, 50Hz

Power consumption: Approx. 16W (Low Power 

≤

 1W)

Operating temperature: 5

°

C to 40

°

C

Storage temperature: –20

°

C to 55

°

C

Weight: Approx. 3.2 kg

Dimensions: 360 mm (W) x 289 mm (D) x 93 mm (H)

VIDEO

Input: 1.0 Vp-p, 75 ohm

Output: 1.0 Vp-p, 75 ohm

S/N ratio: 45 dB min. (SP mode)

Horizontal resolution: Approx. 260 lines (SP mode with Super Picture)

AUDIO 0 dBs = 0.775 Vrms

Input: Line1: –3.8 dBs, 10k ohm

Line2: –3.8 dBs, 10k ohm
Line3: –5.0 dBs,  47k ohm

Output: Line1: –3.8 dBs, 1k ohm

Line2: –3.8 dBs, 1k ohm
REAR RCA: –5.0 dBs,  1k ohm

S/N ratio: 46 dB min. (SP mode)

Frequency responce: 80 Hz ~ 10 kHz (SP mode)

80 Hz ~ 5 kHz (LP mode)

Hi-Fi Dynamic Range: 85 dB min.

Hi-Fi Wow and Flutter: 0.005%

Hi-Fi Frequency Responce: 20 Hz ~ 20 k Hz

Hi-Fi Distortion: 0.5% max.

Hi-Fi Crosstalk @ 1kHz: 55 dB min.

Accessories included: 75 ohm coaxial cable

Operation manual
Infrared remote control
Batteries

As part of our policy of continuous improvement, we reserve
the right to alter design and specifications without notice.

Note: The antenna must correspond to the new standard DIN 45325

(IEC 169 - 2) for combined UHF/VHF antenna with 75 ohm connector.

4

VC-MH73HM
VC-MH730HM

MODEL

VC-MH73HM /
VC-MH730HM

blank

blank

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EP n**

NTSC Luminance Level

0

0

0

0

EP n**

NTSC Chrominance Level

7

7

7

7

SP n**

NTSC Luminance Level

0

0

0

0

SP n**

NTSC Chrominance Level

7

7

7

7

LP P**

PAL Luminance Level

3

3

3

3

LP P**

PAL Chrominance Level

5

5

5

5

blank

blank

---

---

---

---

SP P**

PAL Luminance Level

4

4

4

4

SP P**

PAL Chrominance Level

5

5

5

5

"0"

FIXED

---

---

---

---

JP39

A.DUB

0

0

0

0

JP38

SLOW ATR

0

0

0

0

JP37

INSTANT REPLAY

0

0

0

0

JP36

NTSC PB

1

0

1

1

JP35

NTSC SKEW

0

0

0

0

JP34

HEAD2

0

0

0

0

JP33

HEAD1

1

1

1

1

JP32

HEAD0

0

0

0

0

JP31

PDC 8 bit

1

0

1

1

JP30

L/P-5min

0

0

0

0

JP29

84 CHANNEL

1

0

1

1

JP28

R/C CODE 1

0

0

0

0

JP27

DNR

0

0

0

0

JP26

POST CODE

1

0

1

1

JP25

SAT CTL

1

0

0

0

JP24

AV LINK

0

0

0

0

JP23

Hi-Fi

1

1

1

1

JP22

SORT / CLOCK

1

0

1

1

JP21

DECODER

1

1

1

1

JP20

DOLBY SURROUND

0

0

0

0

JP19

IGR

1

1

1

1

JP18

NICAM

1

1

1

1

JP17

G-CODE 1

1

1

1

1

JP16

G-CODE 0

1

1

1

1

JP15

OEM

0

0

0

0

JP14

LP MODE

1

1

1

1

JP13

F-AV

1

0

1

1

JP12

X2 SCART

1

1

1

1

JP11

VPS 8 bit

1

0

1

1

JP10

TUNER 2

0

1

0

1

JP9

TUNER 1

1

0

1

0

JP8

TUNER 0

1

0

1

0

JP7

SYSTEM 1

0

0

0

0

JP6

SYSTEM 0

0

0

0

0

JP5

SAT SCAN

0

0

0

0

JP4

LOW POWER

1

1

1

1

JP3

SPATIALIZER

0

0

0

0

JP2

VPS/PDC

1

0

1

1

JP1

COLOUR 1

0

0

0

0

JP0

COLOUR 2

0

0

0

0

12 A 6EF7B14

DISPLAY IN HEXADECIMAL NOTATION