Sanyo mr 1020

Page 1

Sanyo Sounds Exciting!

QSANYO

Auto-reverse
Stereo Tape Recorder

MODEL MR-IOZO

SERVICE MANUAL
SANYO ELECTRIC 00., LTD.

INTERNATIONAL DIVISION: SANYO ELECTRIC TRADING C0., LTD.
OSAKA, JAPAN

SPECIFICATIONS
Speed accuracy iZZ, Standard (7-1/2, 3-3/4 ips.) Gain balance (channel-
I3% Standard (1-7/3 ips.) channel) 3 (18 Max. difference (overall record/play)
Speed variation 2% Max. (start to end of reel) Frequency response
Wow & flutter 0.2% Max. 7-1/2 ips. (RMS value) (record/play)
025% Max. 3-3/4 ips. (RMS value) .
. ' H
0.35 3.1, Max. 1-7/8 ips. (RMS value) SPEED 1 FREQUENCY ( Z)
Fast winding time Up to 2 min. for 1200 it, on 7 reel 100 I'm 73:99:,flr 13,109.
Sensitivity Mic. input 770 to 772 dBm for standard rec. level on 74/2 ips. +7 0 __ _ :13,
meter _ l we I'
o . > . 6
AUX. Input 22 to 732 dBm for standard rec. level on 3.3/4 1135- :2 0 -~ :6 -
meter -
Power output 5 Watts each channel 1.7/8 ips. - 0 1-2 " -
(10% dist.)
Cross-talk Reel torque (gr/cm)
(channel-channel) Better than 40 dB MODE FEED REEL TAKE-UP REEL
(track-track) Better than 65 dB 165 400
Bias frequency 30K Hz Play 5 32 200 .
Erase efficiency At least 60 dB Fast
~ - . 0 - 2 7
Signal to noise ratio Better than 40 dB without weighting network Winding 32 200 165 9 0
Hum & noise 40 mV Max. Volume and tone Max. Pinch roller pressure 1.1 . 1_5K gr.
Pad pressure 30 gr.
DISASSEMBLY

To remove the chassis and amplifier circuit from the cabinet in order to
oil the mechanism, follow these steps:

1. Remove the amplifier part and the back of the chassis.
1. Remove the speaker box from the cabinet.
2. Place the set on a cushion with the front panel on the bottom.
3. Remove the four screw on the rear side, and the two on the
bottom (Fig. 1).
4. Open the power source cord container cover and loosen it so that
it will easily separate from the cabinet when it is raised.
5. Lift the cabinet up straight.
Il. Remove the control panel. , ' .5
1. Place the set so that the control panel is on top. , v
2. Pull off the Tone, Volume control, Program selector knobs and
the top and bottom head covers.
3. Remove the Speed selector knob by turning it to the left.
4. Take off the eight screws from the surface of the control panel.
(Fig- 2)
5. Lift ofi the control panel; be careful not to touch the lead cords
for the heads or the auto stop lever. '

Unscrew slx
screws (A...F)

to remove the Ca
Trunk. MN

El;. 1

Page 2

O
O
O
H M
O
ODD iu i i ll " Efilfi O
1 L
Unscrew eight screws
(G...N) to remove the
Control Panel.
Fig. 2

MECHANICAL ADJUSTMENTS

I. Operation button pressure

7/ Fig. 3

duration
button

To gauge how much power is required to change functions by press-
ing an operation button, press the button straight down, at a point
5mm from its edge. Press it with a spring scale (4 or 5 kg), and read
the number at the time the operation button locks (see the figure
below).

The standard pressures for changing operations are shown in the
following table.

PLAY -> STOP

STOP --> TAKE UP p}
stor -> TAKE up 44 less than 3k grt

sror -> PLAY less than 3k grt

Press each DIRECTION button with the spring scale. Read the
scale at the moment the lamp lights; the force required should be
less than 500 gr.

ADJUSTMENT
If abnormal force is required to push an operation button, it can
usually be brought within the above range by oiling the connected
slide lever. In this case grease the contacting surfaces of the opera-
tion button lock slide (61,2 and 3) and the slide supporting metal
(G4 and G5).

I]. Reel base tension

The tension of each reel base should be measured as shown in the
figure below; this tension should be within the following range:
MEASUREMENT couprrrous
Tape speed should be 7-1/2 ips.

Use an empty 3 inch real; on the hub Wind one end of a piece of

thread, and then attach a tension gauge.
thread, and then attach a tension gauge.
1. PLAY tension
Set the reel (with thread and tension gauge) on the right
spindle, as shown in figure 4,
Turn on the power switch and hold the lever to keep the auto
stop from operating Hold the tension gauge parallel with the
plane of the reel and pull it in the rewind direction at a speed
of about 5 cm/sec.
Normal tension is between 50 and 120 gr.
' If the reading is not within this range, adjust as follows:
Change the reel base and slip pully felt.
Change the slip mechanism coil spring (N3) or plate
spring (N7).

less than 2k gr.
less than 3k gr.

-2

mm mi has!

Yenslnn gauge

_|

Fig, 4

2. PLAY and FWD back tension

Set the reel (with the string attached) on the spindle as shown
in figure 5 and tie the tension gauge to the string. Turn on the
power switch and hold the lever to keep the auto stop from
operating, Press the PLAY or TAKE UP p) button, Move
the tension gauge in the direction of the arrow at a speed of
about 5 cm/sec, as shown in figure 5, At the moment the reel
begins moving, read the gauge,

* Normal tension is between 40 and 60 gr.

* Adjustment can be done by changing the back tension lever
(111, J10) at the sides of the left and right reel bases, or by
adjusting the pressure coil spring (J 13) The back tension lever
must be changed if its felt is dusty or oily.

LEM reel bus:

Tension gauge

3. Tension of the motor slip pulley

The motor slip pulley is driven by a belt from the motor pulley.

(See exploded view.)

* Tie a piece of string to the staged, protruding part of the slip
ring L7 (Fig. 6), then connect tension gauge. Put on a tape and
run it in the reverse direction. Hold the slip ring with the
tension gauge attached and read it at the moment it stops
turning in the direction of the arrow.

* Suitable tension is between 40 and 60 gr.

* If it is outside this range, it will adversely atfect the slip motion
timing of the micro switch or cause it to function when it
should not.

* Change the motor slip ring (L7) or adjust the coil spring (19).

Tension gauge Slipping plate (L7)

o .
V
Micro switch _ \

$24 \
CL \
- ,.

® \\ I

o x ,/

FiS- 6