Panasonic NE-7920 User manual

ORDER NBR. MOD-7804-003
Service
Manual
Microwave Oven
NE-7920, NE-7920C
NE-8020
NE-7920, NE-7920C NE-8020
NE-7920, NE-8020 for U.S.A.
NE-7920C for Canada
SPECIFICATIONS
Power Source: 115V AC Single Phase:60 Hz
Power Requirement: 1.42 KW (13.0 A)
High Frequency Output: 700 W : full power
Oscillation Frequency: 2450 MHz
Magnetron: 2M157-M2
Timer: 99 minutes 99 seconds
9 hours 99 minutes for Low power
Cooling Method: Air Cooling
Approximate Outside Dimensions: 24-3/4"" (W) x 18-1/2” (D) x 14-3/4” (H)
63.0 cm (W) x 47.0 cm (D) x 37.5 cm (H)
Approximate Oven Cavity 15-1/2" (W) x 15-1/2” (D) x 9-1/2” (H)
Dimensions: 39.5 cm (W) x 39.5 cm (D) x 24.0 cm (H) ,
Approximate Weight: 71 Ibs ,
32 Kg |
Specifications subject to change without notice.
Panasonic Company
a Division of Matsushita Electric Corporation of America Panasonic Hawaii, Inc. Matsushita Electric of Carmeds L
ig One Panasonic Way, Secaucus, N.J.07094(201)348-7000 320 Waiakamilo Road, Honolulu, Hawaii 96817 5770 Ambler Drive, Missis**4U98, Ont. Law 273
Copyright © 1979 by Matsushita Electric Corporation of America, All rights reserved.
A1

.
This
product
should
be
serviced
only
by
trained
qualified
personnel.
.
Though
this
product
has
been
manufactured
in
compliance
with:
“Federal
Performance
Standard
21
CFR
Subchapter
J”
(HEW):
NE-7920,
NE-8020
or
“Radiation
Emitting
Devices
Act”
(NHW):
NE-7920
it
is
very
important
when
servicing
to
avoid
being
exposed
to
excessive
microwave
radiation.
This
may
be
hazard-
ous.
All
repairs
shoud
be
made
in
accordance
with
procedures
described
in
this
manual.
_
Check
for
radiation
leakage
after
every
servicing
according
to
the
“procedure
for
measuring
radiation
leakage”
on
pages
21
&
22.
.
Any
serviceman
who
learns
of
any
accident
pertaining
to
microwave
radiation
leakage
should
immediately
notify
the
appropriate
address
listed
below.
IN
U.S.A.
PANASONIC
COMPANY
Division
of
Matsushita
*
(MECA)
Electric
Corporation
of
America
One
Panasonic
Way,Secaucus,New
Jersey
07094
Attention:Quality
Assurance
Dept.
(201)
348-7000
IN
HAWAII
PANASONIC
HAWAII,
INC.
(PHI)
320
Waiakamilo
Road,
Honolulu,
96817
(808)
847-5361
IN
CANADA
MATSUSHITA
ELECTRIC
OF
CANADA
LIMITED
(MELCA)
5770
Ambler
Drive,
Mississauga,
Ontario,
L€W
2T3
(416)
624-5010
5.
There
are
special
components
used
in
the
microwave
oven
which
are
important
for
safety.
These
parts
are
shaded
on
the
schematic
diagram
and
on
the
replacement
parts
list.
It
is
essential
that
these
critical
parts
should
be
re-
placed
with
manufacturer’s
specified
parts
to
prevent
microwave
leakage,
shock,
fire,
or
other
hazards.
Do
not
modify
the
original
design.
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Precautions
to
be
observed
before,
and
during
servicing
to
avoid
possible
exposure
to
excessive
Microwave
CNELGY
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Cautions
to
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when
troubleshooting.
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Disassembly
and
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replacement
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Measurements
and
adjustments
(Including
the
Safety
Interlock
Switch
Circuit)............
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Procedure
for
measuring
radiation
leakage
.....
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Customer
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Component
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procedure
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Digital
programmer
circuit
test
procedure.
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Necessary
tools
and
measuring
instruments.
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;

INSTALLATION
1, Check the grounding. 5. Position the microwave oven away from radios,TV’S,
2. Confirm the power source capacity. etc.
3. Use the microwave oven in an ambient temperature 6. Place the microwave oven on a stable base.
of less than 104 F(40°C). 7. Avoid placing anything on the top cover of the
4. Avoid using the microwave oven where humidity is microwave oven that may interfere with the exhaust
high. vents.
OPERATION
———— Air Vent
Simulated Wood
Grain Cabinet
Control Panel
Turntable
Safety Door Lock System
CONTROL PANEL Fig. 1
NOTE: Model NE-8020 is provided with a capacitive touch control panel. A membrane push switch control panel is used
for models NE-7920 and NE-7920C.
NE-8020
Panasonic
2
See
Clock
Set
Button
Power/Time Stage Indicator Lights | _proveim onan A err ae ) Auto Sensor Status Indicator Lights
Timed Defrost Indicator Light
Digital Readout Display Window
P Indicator Light
RPP eee emg ae (clock/time/auto)
TIME & POWER COOKING PADS [7 Fy] (2. | E | 2 Gis Time es
See
So
See
Poe!
[1
||
Ges6)
heaa|
Gena
Cas
Power Select Pad rT oa [ = ] | Stand
Defrost Select Pad : —
Delay/Stand Select Pad—!| | [_ut2SensorContrr_} AUTO SENSOR CONTROL PADS
[ ac ] I aa COOK Select Pad
Mt DEFROST-COOK Select Pad
| etcatme [ eauienll COOK-WARM Select Pad
SE age eNOS DEFROST-COOK-WARM Select Pad
Al: Rehect Pasta Convenience Foods
Canned Foods
A2: Besi/Lamb-Well Beef/Lamb-Weil
A: Sealants Beat Lant-Med —] Auto Sensor Cooking Guide
Aa: bets, Beet-Rare Poultry
AS: Potatoes Carrots Fish Sea Foods
‘AG: Froz.Veg Chops Chops Hamburgers |
Consult Genius Guide tor proper cooking procedures f
Reset/Stop Pad pois (= Hy sen Pad
lhe .
“Genius
L MICROPROCESSOR CONTROL
Ad

NE-7920, NE-7920C |
Panasonic mio =— Clock Set Button
Auto Cook Indicator Light
Auto
Defrost-Cook
Indicator
Light
re
.?;
t=
=I
Delay/Stand
Indicator
Light
7
le
Power
Indicator
Lights
Lt
eco
s
=
Timed
Defrost
Indicator
Light
Digital
Readout
Display
=)
Wi
lock/ti
t
TIME
&
POWER
COOKING
PADS
indow
(clock/time/auto)
ee
a
ee
apa
[2]
[3]
7
Clock
Time
Auto
ime
ect
Fads
I
min
min
sec
sec
tee
eet
|
lee
oe
’
of
Defrost
Select
Pad
|
im
AS
Power
Select
Pad
ct
ont
|
[
roe
i=
AUTO
SENSOR
CONTROL
PADS
Delay/Stand
Select
Pad
—
COOK
Select
Pad
DEFROST-COOK Select Pad
i
i
Reset/Stop
pad
|
=
Pad
Auto Cook, Auto Def-Cook
Al Rehect Pasta A1 : Convenience Foods
Canned Foods
Pork Pot Roast
A3 Beet/Lamb-Med —-A3.: Beet Lamb-Med
Bacon Rice
Aa Beel-Rare A4: Beel-Rare Poultry
Fish Poullry
AS Polaloes Carrots AS: Fish Sea Foods
Auto Sensor Cooking Guide
AB Froz Veg Chops AG: Chops Hamburgers
Longuit Genius Gumte for penper cooking procedures
|
A2 Beel/Lamb-Well A2:Beel Lamb-Well
Pork
l
i
“ Cenius
:
MICROPROCESSOR
CONTROL
Fig. 3
NOTE:
When
the
oven
is
first
plugged
in,
Reset/Stop
pad
should
be
tapped
to
clear
the
display
window
orindicator
lights.
CONTROLS
Clock Set Button
When
oven
is
first
plugged
in,
the
Dispay
Window
will
show
00:00
and
the
colon
will
blink.
Exter
the
time
of
day
(TOD)
by
tapping
the
appropriate
Tinne
Select
Pads.
Example: If it is 10:25 (a.m. or p.m.), tap the 10 min.
pad once, the 10 sec. pad tvice, and 1 sec.
pad 5 times. The Display Wnclow will show
10: 25 with the colon blinking.
Push the Clock Set Button. The colon stops
blinking.
The
clock
is
set
ad
will
keep
the
TOD as long as the unit isplugged in and
electric energy is supplied.
NOTE: To reset the TOD in the Uisplay Window,
push the Clock Set Button aagn to clear the
time. Zeros (00:00) will jgoear with the
colon blinking. Enter the osrect TOD by
following the above procedure
a4

Timer Select Pads
[7 Y
‘is ao)
min Y, sec y,
min. min. — sec. sec.: : ‘Basic Time Setting
hour “H” min. min. --DELAY/STAND & LOW
Example 1: High — 13 min. 465 sec.
10min. pad : 1 tap
1min. pad : 3 taps
10sec. pad : 4 taps
1sec. pad :5 taps
Example 2: Low — 2 hours 25 min.
10 min. pad : 2 taps
10sec. pad : 2 taps
1 sec. pad :5 taps
*When DELAY/ STAND and (or) LOW are selected, the
Time
Select
Pads
change
to
hours
and
minutes.
The
ten
(10)
minute
pad
will
program
hours
in
the
display
window.
The
one
(1)
minute
pad
will
be
inoperable
and
display
H,
indicating
hours.
The
seconds
pads,
ten
(10)
and
one
(1),
will
program
minutes
in
the
display
window.
No
visible
second
countdown
will
be
seen
in
the
display
window
until
59
minutes
remain.
The
timer
will then display minutes and seconds.
Power Select Pad
ee $$
VA
Delay
Defrost Power / Stand
jtao : HIGH power 4taps :M. LOW power
2taps: M.HIGH power 5Staps :LOW power
3taos: MEDIUMpower 6taps :WARM power
NOTE: The following selections for 2-or 3-stage program
cooking are available in addition to any combina-
tion of powers.
© The same power in succession.
HIGH—> HIGH—>HIGH
e
Any
combination
of
powers
and
Stand.
HIGH—-*LOW->STAND
HIGH—>STAND—>LOW
@ Defrost to any combination
DEFROST->HIGH—>LOW
e Defrost to combination of any power and Stand.
DEFROST->HIGH->STAND
DEF ROST—>STAND-HIGH
© Delay to any combination of powers.
DELAY->HIGH*LOW
Delay to combination of any power and Stand.
DELAY+HIGH=STAND
of powers.
Defrost Select Pad
When
Defrost
is
selected,
the
cycle
will
also
program
an
automatic
stand
time
equal
to
defrost
time.
NN
Delay
=) |
|
Power
A,
Defrost
w
J
!
Delay
Power Stan y
LE
U
Delay/Stand Pad
To delay cooking or to program Stand Time after
cooking is completed.
NOTE: It is not always advisable to use Delay Start
when selecting any defrost function by time or
Auto Sensor cooking. If left in the oven too
long, some defrosting may take place before
Defrost or Auto Sensor cooking begins, causing
inacurate end results.
Auto Sensor Control Pads
Ttap : AUTO1 4taps : AUTO4
2taps : AUTO 2 5taps : AUTOS
3taps : AUTO 3 6 taps : AUTO6
For cooking foods from their natural storage places.
Meats, vegetables, casseroles, cake, etc.
Auto Sensor Control
Ea
Def-Cook
Def-Cook-Warm Cook-Warm
i
Defrost —Cook
For defrosting and cooking foods from the frozen state.
Meats, convenience foods, casseroles. etc.
Auto Sensor Control
[SI
SN
XS
Det-Cook-Warm Cook-Warm
O
Defrost-Cook—Warm] (Only for model NE-8020)
A complete cycle to defrost and cook foods from
frozen state, then keep warm for 1 hour. (If foods are
removed at end of cook, allow to stand according to
recipe directions).
Auto Sensor Control
EE =
(Only for model NE-8020)
For cooking foods from their natural storage place, then
keep warm for 1 hour.
(If foods are removed at end of cook, allow to stand
according to recipe directions.)
Auto Sensor Control
[ =» | | aie i
==) ZZ
AS

Reset/Stop
Pad
EA\_~ ||
Before
cooking:
One
tap
clears
instructions.
During
cooking:
One
tap
temporarily
stops
the
cooking
progress.
Another
tap
cancels
all
programs
and
TOD
reappears
in
the
Display
Window.
(=| ZZ
One
tap
begins
cooking.
If
door
is
opened
or
Reset/
Stop
Pad
is
tapped
once
during
cooking,
Start
Pad
must
always
be
tapped
to
begin
cooking
operation.
Start Pad
——————
Beep Sound
When a correct Pad is tapped. a beep sound is heard.
If a Pad is tapped and no beep sound is heard, the unit
has not or cannot accept the instruction. Two beeps
will sound between stages. At the end of any complete
program, five beeps will be heard.
Opening Door
Opening the door during cooking will stop the cooking
progress without cancelling program. Cooking resumes
as soon as the door is closed and Start Pad is tapped.
The oven light will turn on whenever the door is opened.
OPERATION PROCEDURE
SUMMARIZED
DIRECTIONS
Time
Cooking
=
NE-8020, NE-7920, NE-7920C
Auto Sensor Cooking
One-Stage Cooking
Set Power
Set Time
Tap START Pad
Defrost Cycle
Tap DEFROST Pad
Set Time
Tap START Pad
Set Auto Program (A1-A6, for COOK
DEF-COOK)
Tap START pad
Two-Stage Cooking
Set first Power
Set first Time
Set second Power
Set second Time
Tap START Pad
Defrost-to-Cook Cycle
Tap DEFROST Pad
Set Time
Set second Power
Set second Time
Tap START Pad
NE-7920, NE-7920C
Three-Stage Cooking
Set first power
Set first Time
Set second Power
Set second Time
Set third Power
Set third Time
Tap START Pad
Defrost-to-Two Stage
Cook Cycle
Tap DEFROST Pad
Set Time
Set second Power
Set second Time
Set third Power
Set third Time
Tap START Pad.
Set Auto Program (A1-A6, for COOK.
WARM,DEF-COO K-WARM)
Tap START pad
A6

NE-8020
TIME
COOKING
PROCEDURE
One-Stage Cooking
Step 1.
Step 2.
Step 3.
Defrost
Step 1.
Step 2.
Step 3.
Set cooking power by tapping the POWER
Pad to the appropriate power.
Example: Tap POWER Pad twice for M. High.
—Clock time disappears, zeros (00 00) appear
in the Display Window. Indicator Light
appears above the power selected. STAGE 1
Indicator Light turns on.
Set cooking time by tapping the appropriate
Time Pads.
Example: To set 15 minutes and 30 seconds,
tap 10 min. pad once, 1 min. pad 5 times,
10 sec. pad 3 times.
—The cooking time appears in the Display
Window.
Touch START Pad.
—Microwave activity starts. STAGE1 Indicator
Light blinks.
Turntable begins to rotate. Oven tight turns
on and cooking time begins to count down.
—When cooking time has elapsed, oven beeps
and turns off automatically. Turntable stops.
Power Indicator, STAGE 1 Indicator light and
oven light turn off. TOD reappears in the
Display Window.
Touch DEFROST Pad.
—Clock
time
disappears,
zeros
(00
00)
appears
in
the
Display
Window.
Defrost
Indicator
Light
and
STAGE
1
Indicator
Light
turn
on.
Set
defrost
time
by
tapping
Time
Pads.
(Refer
to
Step
2
under
One-Phase
Cooking.)
—The
defrost
time
appears
in
the
Display
Window.
Touch START Pad.
—Microwave
activity
starts.
Oven
light
turns
on,
STAGE
1
Indicator
Light
blinks.
Turn-
table
begins
to
rotate.
Defrost
time
begins
to
count
down.
Turntable
keeps
rotating.
—When
the
defrost
time
counts
down
to
‘0
the
defrost
time
reappears
in
the
Display
Window.
STAGE
1
Indicator
Light
stops
blinking
and
remains
on.
Defrost
Indicator
Light
also
remains
on.
Microwave
activity
stops
and
oven
begins
stand
time.
Turntable
keeps
rotating.
—When
the
stand
time
displayed
counts
down
to
‘0’,
the
oven
beeps
and
turns
off
auto-
matically.
Oven,
Defrost
and
STAGE
1
Indicator
Lights
turn
off.
Turntable
stops.
The
TOD
reappears
in
the
Display
Window.
ow
'
Three-Stage Programmed Cooking
Step 1.
Step 2.
Set
first
cooking
power
by
tapping
POWER
Pad to the appropriate power
(Refer to Step 1 under One—Stage Cooking.)
—Clock time disappears, zeros (00 00) appear
in
the
Display
Window.
Power
Indicator
Light appears above the selected power.
STAGE 1 Indicator Light turns on.
Set first stage cooking time by tapping the
appropriate Time Pads.
(Refer to Step 2 under OneStage Cooking.)
—First stage cooking time appears in the
Display Window.
Step 3.
Step 4.
Step 5.
Step. 6.
Step, 7.
AT
Set second stage cooking power by tapping
POWER Pad to the appropriate power.
—First stage time disappears. Zeros (00 00)
appear in the Display Window.
—Second stage cooking Power Indicator Light
appears above the power selected. First stage
cooking Power Indicator Light turns off.
STAGE 2 Indicator Light turns on. STAGE
1 Indicator Light remains on.
Set second stage cooking time by tapping the
appropriate Time Pads.
—Second stage cooking time appears in the
Display Window.
Set third stage cooking power by tapping
POWER Pad to the appropriate power.
—Second stage time disappears. Zeros (00 00)
appear in the Display Window.
—Third stage cooking Power Indicator Light
appears above the power selected. Second
stage cooking Power Indicator Light turns off.
STAGE 3 Indicator Light turns on and
STAGE 1 and 2 Indicator Lights remain on.
Set third stage cooking time by tapping the
appropriate Time Pads.
—Third stage cooking time appears in the
Display Window.
Touch START Pad.
—Third stage cooking time disappears and
first stage cooking time reappears in the
Display Window and begins to count down.
First stage Power Indicator Light turns on.
Second and third stage Power Indicator
Lights remain off. STAGE 1 Indicator
Light starts to blink and STAGE 2 and 3
Indicator Lights remain on. Oven light
turns on. Turntable rotates. Microwave
activity begins.
—When the first stage cooking time has elapsed,
a beep sounds twice. Second stage cooking
time reappears in the Display Window and
begins to count down. First stage Power
Indicator Light and STAGE 1 Indicator Light
turn off. STAGE 2 Indicator Light starts to
blink. Second stage Power Indicator Light
comes on.
—When the second stage cooking time has
elapsed, a beep sounds twice. Third stage
cooking time reappears in the Display Win-
dow and begins to count down. Second
stage Power Indicator Light and STAGE 2
Indicator Light turn off. STAGE 3 Indicator
Light starts to blink. Third stage Power
Indicator Light comes on.
—When the third stage cooking time has elapsed ,
five beeps are heard and oven turns off
automatically. Third stage Power I!ndicator
Light and STAGE 3 Indicator Ligh turn off.
Oven light turns off and turntable stops.
TOD reappears in the Display Window.

NE-8020
AUTO
SENSOR
COOKING
For
proper
cooking
results
on
Auto
Sensor
program,
be
sure
to
cover
foods
tightly
with
plastic
film,
or
place
in
a
glass
casserole
with
lid
as
directed
by
recipe.
Step 1.
Step 2.
Select
the
appropriate
Auto
Sensor
Control
Pad—COOK,
DEF-COOK,
DEF-COOK-WARM
or
COOK-WARM.
Tap
the
selected
Auto
Sensor
Control
Pad
until
desired
program
appears
in
the
Display
Window.
Itap....A1
3taps...A3
Staps.
..
AS
2taps...A2
4taps...A4
G6taps...
A6
—Clock
time
disappears.
The
selected
Auto
Sensor
Program
appears
in
the
Display
Window.
Auto
Status
Indicator
Light(s)
turns
on.
Touch START Pad.
—Oven
light
turns
on.
Auto
Status
Indicator
Light
of
first
operating
status
starts
to
blink
and
other
Auto
Status
Indicator
Lights
remain
on.
Microwave
activity
starts.
Turn-
table
rotates
and
oven
light
turns
on.
—Oven
will
operate
automatically
according
to
the
selected
Auto
Cook
function.
—When Auto Sensor program disappears,
a
beep
sounds
twice
and
a
time
will
appear
in
the
Display
Window
indicating
the
ramainder
of
the
cooking
time
and
will
start
to count down.
COOK
Status
Indicator
Light
continues
to
blink.
—When Auto Sensor Cooking is over, COOK
Status
Indicator
Light
turns
off,
oven
beep
5
times
and
oven
shuts
off
automatically.
TOD
reappears
in
the
Display
Window.
—When Auto Sensor program disappears a beep
sounds
twice
and
a
time
will
appear
in
the
Display
Window
indicating
the
remainder
of
the cooking time and will start to count down.
DEF Status Indicator Light turns off and
COOK Status Indicator Light starts to
blink.
—When Auto Sensor DEF-COOK Cooking is
over, COOK Status Indicator Light turns off,
5
beeps
are
heard,
and
oven
shuts
off
auto-
matically.
TOD
reappears
in
the
Display
Window.
—When Auto Sensor program disappears, a beep
sounds twice and a time will appear in the
Display Window indicating the remainder of
COOK status time and will start to count
down. COOK Status Indicator Light
continues to blink.
—When COOK status time is over, a beep
sounds twice and 60 min. (6000) will appear
in the Display Window indicating the WARM
time and starts to count down. COOK Status
Indicator Light turns off, and WARM Status
Indicator Light begins to blink.
—When Auto Sensor COOK-WARM is over,
WARM. Status Indicator Light turns off,
a beep sounds 5 times and oven shuts off
automatically. TOD reappears in the Display
Window.
an
—When Auto Sensor program disappears,
a beep sounds twice and a time will appear
in the Display Window indicating the re-
mainder of cooking time and begin to count
down.
DEF Status Indicator Light turns off and
COOK Status Indicator Light starts to blink.
—When COOK Status time is over, a beep
sounds twice and 60 min, (6000) will appear
in the Display Window indicating the WARM
time and starts to count down.
COOK Status Indicator Light turns off, and
WARM Status Indicator Light begins to blink.
—When Auto DEF-COOK-WARM is over,
WARM Status Indicator Light turns off, and a
beep sounds 5 times and oven shuts off
automatically. TOD reappears in the Display
Window.
NE-7920,
NE-7920C
TIME
COOKING
PROCEDURE
One-Stage Cooking
Step
1.
Set
cooking
power
by
tapping
the
POWER
Pad
to
the
appropriate
power.
Example:
Tap
POWER
Pad
twice
for
M.
High.
—Clock
time
disappears,
zeros
(00
00)
appear
in
the
Display
Window.
Power
Indicator
Light
appears
above
the
power
selected.
Step
2.
Set
cooking
time
by
tapping
the
appropriate
Time
Pads.
Example:
To
set
15
minutes
and
30
seconds,
tap
10
min.
pad
once,
1
min.
pad
5
times,
10
sec.
pad
3
times.
—The
cooking
time
appears
in
the
Display
Window.
Step
3.
Touch
START
Pad.
—Microwave
activity
starts.
Power
Indicator
Light
blinks.
Turntable
begins
to
rotate.
Oven
light
turns
on
and
cooking
time
begins
to
count
down.
—When
cooking
time
has
elapsed,
oven
beeps
and
turns
off
automatically.
Turntable
stops.
Power
Indicator
Light
and
oven
light
turn
off.
TOD
reappears
in
the
Display
Window.
Defrost
Step 1. Touch DEFROST Pad.
—Clock time disappears, zeros (00 00) appear
in the Display Window. Defrost Indicator
Light turns on.
Step 2. Set defrost time by tapping Time Pads. (Refer
to Step 2 under One-Stage Cooking)
—The defrost time appears in the Display
Window.
Step 3. Touch START Pad.
—Microwave activity starts. Overs light turns
on. Defrost Indicator Light blinks. Turntable
begins to rotate. Defrost time begins to
count down.
~When the defrost time counts down to ‘‘O",
the defrost time reappears in the Display
Window. Defrost Indicator Light stops
blinking and remains on. A beep sounds
twice. Microwave activity stops and oven
begins stand time. Turntable keeps rotating.

—When the stand time displayed counts down
to ‘0’, the oven beeps and turns off automat-
ically. Oven light, Defrost Indicator Light
turn off. Turntable stops. The TOD re
appears in the Display Window.
Three-Stage Programmed Cooking
Step 1.
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Step 7.
Set first cooking power by tapping POWER
Pad to the appropriate power.
(Refer to Step 1 under One-Stage Cooking.)
—Clock time disappears, zeros (00 00) appear
in the Display Window. Power Indicator
Light appears above the selected power.
Set first stage cooking time by tapping the
appropriate Time Pads.
(Refer to Step 2 under One-Stage Cooking.)
—First stage cooking time appears in the
Display Window.
Set second stage cooking power by tapping
POWER Pad to the appropriate power.
—First stage time disappears. Zeros (00 00)
appear in the Display Window.
—Second stage cooking Power Indicator Light
appears above the power selected. First
stage cooking Power Indicator Light turns off.
Set second. stage cooking time by tapping the
appropriate Time Pads.
—Second stage cooking time appears in the
Display Window.
Set third stage cooking power by tapping
POWER Pad to the appropriate power.
—Second stage time disappears. Zeros (OO 00)
appear in the Display Window.
—Third stage cooking Power Indicator Light
appears above the power selected. Second
stage cooking Power Indicator Light turns
off.
Set third stage cooking time by tapping the
appropriate Time Pads.
—Third stage cooking time appears in the
Display Window.
Touch START Pad.
—Third stage cooking time disappears and first
stage cooking time reappears in the Display
Window and begins to count down. First
stage Power Indicator Light turns on and
starts to blink. Second and third stage
Power Indicator Lights turn on. Oven light
turns on. Turntable rotates.
Microwave activity begins.
—When the first stage cooking time has elapsed,
a beep sounds twice. Second stage cooking
time reappears in the Dislay Window and
begins to count down. First stage Power
Indicator Light turns off. Second stage
Power Indicator Light starts to blink. Third
stage Power Indicator Light remains on.
—When second stage cooking time has elapsed,
a beep sounds twice. Third stage cooking
time reappears in the Display Window and
begins to count down. Second stage Power
Indicator Light turns off.
Third stage Power Indicator Light starts to
blink.
—When the third stage cooking time has elapsed,
five beeps are heard and oven turns off
automatically. Third stage Power Indicator
Light turns off. Oven light turns off and
turntable stops. TOD reappears in the
Display Window.
AQ
NE-7920, NE-7920C AUTO SENSOR COOKING
For proper cooking results on Auto Sensor program,
be sure to cover foods tightly with plastic film, or
place in a glass casserole with lid as directed by recipe.
Step 1. Select the appropriate Auto Sensor Control
Pad — COOK or DEF-COOK.
Tap the selected Auto Sensor Control Pad until
desired program appears in the Display Window.
ltap....A1l S3taps...A3 5 taps... A5
2taps...A2 4taps...A4 6 taps... A6
—Clock time disappears. The selected Auto
Sensor Program appears in the Display
Window. Auto Indicator Light turns on.
Step 2, Touch START Pad.
—Oven light turns on. Auto Indicator Light
starts to blink. Microwave activity starts.
Turntable rotates.
—Oven will operate automatically according
to the selected Auto Cook function.
—When Auto Sensor program disappears,
a beep sounds twice and a time will appear
in the Display Window indicating the
remainder of the cooking time and will start
to count down. Auto COOK Indicator Light
continues to blink.
—When Auto Sensor Cooking is over, Auto
COOK Indicator Light turns off, oven beep
5 times and oven shuts off automatically.
TOD reappears in the Display Window.
—When Auto Sensor program disappears, a beep
sounds twice and a time will appear in the
Display Window indicating the remainder
of the cooking time and will start to count
down. Auto DEF-COOK Indicator Light
continues to blink.
—When Auto Sensor DEF-COOK Cooking is
over, Auto DEF-COOK Indicator Light turns
off . 5 beeps are heard, and oven shuts off
automatically. TOD reappears in the Display
Window.
NOTE: When the oven calculates the balance of cooking
time to be over 60 minutes, the time will appear
as hours and minutes.
Example:!f time should be 94 minutes, the
Display Window will show 1H34. The seconds
will not visibly count down in the Display
Window until the 35 minutes has elapsed and
only 59 minutes remain. At that time the
unit will again show minutes and seconds.
Seconds will visibly count down.
IMPORTANT
1. Auto Sensor cooking is successful only with the foods
and recipes found in the Auto Sensor Cooking Guide.
Because of the vast differences in food cornposition,
items not mentioned in this Cooking Guide should
be prepared in your microwave oven using Power
Select and Time features. Please consult Variable
Power Microwave Cookbook for procedures.
2. When cooking with Auto Sensor, do not interrupt
the oven for more than one minute for better cooking
result as long as Auto Sensor (A1-A6) is indicated in
the Display Window.
3. All foods for Auto Sensor Cooking on COOK or
COOK-WARM are taken from their normal storage
place.

4. All foods for Auto Sensor Cooking on DEFROST-
COOK or DEFROST-COOK-WARM should be
solidly frozen.
5. Before using Auto Sensor feature, make sure glass
tray in the oven is dry to assure best Auto cooking
results.
6. Room temperature or heat surrounding the oven
should not be above 95 degrees F when using the
Auto Sensor Cooking cycle. Inaccurate cooking may
result.
7. Foods less than 3 or 4 ounces should be cooked by
power and time, not by the Auto Sensor Cooking
program.
AUTOMATIC CHECKING MECHANISM
1. If
“E”
indication
appears
in
the
Display
Window:
You
might
have
given
wrong
instruction.
“‘E’’,
indi-
cating
ERROR,
appears
under
following
conditions.
*When
Auto,Sensor
Cooking
is
selected
after
Time
and Power cooking.
»*When
Defrost
power
and
Time
is
selected
together
with
Auto
Sensor
cooking.
*When more than two Auto Sensor Programs are
selected
at
a
time
by
using
different
Auto
Cook
functions.
(When
same
Auto
Cook
function
is
selected two or three times, A1-A6 only appear in
the Display Window.)
*When 4th stage cooking is selected.
*When
clock
is
set
later
than
12:59
or
at
impossible
time
like
00:73
or
83:25.
Touch
RESET
Pad
to
clear
““E'’
from
Display
Window
and
enter
correct
instructions.
2.
\f
Auto
Sensor
Control
should
not
work
properly,
oven
is
designed
to
shut
off
automatically
60
minutes
after
operation
begins
and
to
show
‘‘FFFF”
in
the
Display
Window.
Touch
RESET
Pad
to
clean
“F’’
from
the
Display
Window
and
check
if
the
quantity
of
food
should
be
proper
for
Auto
Sensor
cooking.
3.
When the oven is not being used for cooking the
Display Window will show TOD. If the oven is
affected by temporary power failure or the plug is
removed and reinserted, the Display Window will
show zeros (00:00) with blinking colon automatically.
To reset the correct TOD, simply follow the clock
set instructions.
OQ Q [on] OQ OQ
M.High Med M.Low Low Warm
Fig. 4
ae
CF OFF
fas) Oo fas) jam) jos) oO
High M.High Med M Low Low Warm
Fig. 5
CAUTION WHEN USING
1. Do not use metalware
In
rare
cases
where
you
must
use
meta!
materials
such
as
foil
or
skewers,
etc.,
take
care
not
to
have
the
edge
of
the
metal
material
touch
the
inner
glass
screen,
or
the
oven
walls
(coated
steel),
because
the
glass
plate
may
be
broken
or
the
coated
part
may
be
burned by sparking.
2.
Always
keep
the
glass
cooking
tray
clean
Do
not
cook
foods
with
a
high
fat
or
sugar
content
directly
on
the
glass
tray.
3.
Do
not
dry
clothes
in
the
microwave
oven.
4.
Avoid
using
wooden
containers
for
more
than
a
few
seconds.
5.
Do
not
operate
the
oven
with
a
kitchen
towel
or
a
napkin
left
between
the
door
and
the
front
wall
of the oven.
Do
not
press
the
cook
button
when
the
oven
is
empty.
Keep the inside of the oven clean.
.
Avoid
cooking
a
small-volume
of
food
for
a
long
period of time.
.
If
any
visible
steam
or
moisture
is
found
on
or
around the door just wipe it off. There is no need
© MNO
A10
10.
11.
12.
for concern and this never causes any microwave
leakage.
Cautions when operating the control panel.
A. Do not touch control pads with water or oil on
your finger.
When the control panel is dirty, wipe with a
damp cloth first and then finish with a soft dry
cloth. Do not use harsh detergents or abrasives.
B. Do not try to touch the pads while wearing
gloves or while holding any insulating materials.
C. For most accurate programming of the unit,
tap the center of each pad firmly.
D. Do not hit or strike the control panel since this
is made of glass and may be broken.
When power select is set at a setting other than High,
the intensity of the oven light will vary. This is
normal and indicates that the oven is operating
normally.
Do not put your watch directly on the turntable.
Mechanics of the turntable utilize magnetic capsules
and might damage your watch.

SCHEMATIC DIAGRAM
NOTE; DOOR IS CLOSED.
GROUND
7} CHASSIS
PLUG
WHITE BLACK
ud
= OVEN LIGHT
= 125V 30W
AC 115V
60Hz 3
Cd
[SWITCH ®
S| VARISTOR aes
reo
OVEN LIGHT
SWITCH
THERMAL
CUTOUT
(OVEN)
GREEN
BLACK
Low
THERMAL] VOLTAGE
CUTOUT| TRANS.
(MAGNETRON
DIGITAL
PROGRAMMER
» CIRCUIT
IMPORTANT SAFETY NOTE;THE SHADED AREA ON THIS SCHEMATIC DIAGRAM INCORPORATES SPECIAL FEATURES
IMPORTANT FOR PROTECTION FROM MICROWAVE RADIATION. FIRE AND ELECTRICAL SHOCK HAZARDS. WHEN SERVICING
IT IS ESSENTIAL, THAT ONLY MANUFACTURERS SPECIFIED PARTS BE USED FOR THE CRITICAL COMPONENTS
IN THE SHADED AREAS OF THE SCHEMATIC DIAGRAM.
Ww WHITE
OR ae ee
aw BROWN-BIU
W/OR | WHITE-ORA NGE
LATCH
SWITCH A
eS
INDICATES
HARNESS LEAD
-OVEN LIGHT
SWITCH
SHORT
SWITCH
SHIELD WIRE-LEAD
SENSOR ELEMENT
NOTE;( )ONLY APPLY FOR NE-8020.
manual.
AN
Fig. 6
NOTE:
This
circuit
does
not
contain
102
resistor.
Please
refer
to
the
component
test
procedure
on
page
28
of
te
service

PS HIGH-VOLTAGE
VARIABLE POWER
SWITCH
HIGH-VOLTAGE
TRANSFORME R
Fig. 7
CIRCUIT
Refer to the schematic diagram on page 11.
1. When the food is placed inside the oven and door is
closed.
(A) The low voltage transformer supplies the necessary
voltage to the digital programmer circuit when
power cord is plugged in.
The contacts of the short switch open. This switch
creates short circuit to blow 15 A fuse and stop
magnetron oscillation when door is opened during
operation under abnormal condition (i.e. both the
contacts of latch switch A and B do not open the
circuit to stop oscillation.)
The door keyes are caught by the door hooks, the
contacts of latch switch A and B close the primary
circuit.
(D) The oven light. switch is activated to turn off the
oven light. The oven light turns on while the door is
opened or the magnetron oscillates.
(B)
(C
2. When cooking power and cooking time are set.
(ONE-STAGE COOKING)
(A) Power indicator light above the power selected
turns on and stage 1 indicator light for model
NE-8020 turns on.
(B) The time you set appears in the display window.
(C) The digital programmer circuit memorizes the
function you set.
3. When the start pad is touched.
(A) 115 V A.C. is applied to the high voltage trans-
former through the power relay contacts which are
closed by the digital programmer circuit.
Fan motor starts rotating and cools the magnetron
by blowing the air coming from the intake on the
back panel over the magnetron fins. Also the fan
motor drives the turntable by means of gears,
belts and pulleys for uniform cooking. (See fig.9)
The oven light turns on.
Power indicator light (NE-7920 and NE-7920C)
or stage 1 indicator light (NE-8020) starts blinking
to indicate magnetron oscillation.
Cooking time starts counting down.
(B)
(C)
(D)
VARIABLE POWER
HIGH-VOLTAGE = SWITCH
CAPACITOR
CHASSIS HIGH-VOLTAGE
TRANSFORMER
Fig. 8
DESCRIPTION
—At2
Fan motor
Pulley D
MAGNET POLARITY
Turntable
5
Pulley D
Oven cavity bottom
Fig. 9
(E) 20V A.C. is supplied to the digitd programmer
circuit from the high voitage transform er.
3.2 volts AC is generated from the filament winding
of the high voltage transformer. This 3.2 volts is
applied to the magnetron to heat tne magnetron
filament through two noise preventing choke coils.
A high voltage of 2,800 volts AC is generated in the
secondary of the high voltage transformer and this
secondary voltage is increased by the action of the
diode and the charging of the high volage capacitor.
This resultant DC voltage is then applied to the
anode of the magnetron. As shown in fig.10, the
first half cycle of the high voltage proaduced in the
high voltage transformer secondry chyrges the high
(F)
(G)

voltage
capacitor.
Current
flow
is
in
the
direction
of
the
dotted-line
---»
During
the
second
half
cycle,
the
voltage
produced
by
the
transformer
secondary,
and
the
charge
of
the
high
voltage
capacitor
are
combined
and
applied
to
the
magnetron
as
shown
by
the
solid-line
—-=so
that
oscillation
begins.
the
disturbance
wave
generated
by
the
magnetron
is
prevented
by
the
choke
coils
of
1.6uH,
filter
ca-
pacitors
of
500pF
and
the
magnetron’s
shielded
case
so
that
TV
and
radio
programs
are
not
impaired
by
noise.
MAGNETRON
‘ VARIABLE
HIGH-VOLTAGE | POWER
CAPACITOR SWITCH
A.C 2800V
TRANSFORMER
Fig. 10
(H) The coil of variable power switch is energized
intermittently by the digital programmer circuit,
when the oven is set at any power selection except
for High power position. The digital programmer
circuit controls the ON-OFF time of the variable
power switch contacts in order to vary the output
power of the microwave oven from ‘‘Warm" to
“High'’ power. One complete ON and OFF cycle of
the variable power switch is 22 seconds.
The relation between indications on the control
panel and the output of the microwave oven is as
shown in fig.11.
OUTPUT POWER ON, OFF TIME ON
INDICATION AGAINST VARIABLE
HIGH POWER POWER SWITCH
22/22 (100%) |S Fn
01S}.
20/22 (91%) aon fol on ote
Me
fe]
Warm 2/22 (10%) ON es OFF °
Warm
in Auto 1/22 (4.5%)
Cooking
d fe]
OF
OFF
Fig. 11
A13
4. When the door is opened during cooking.
(A) Latch switch A (primary) and latch switch B
(secondary) open to cut off the primary voltage
to the high voltage transformer to stop microwave
oscillation.
(B) Power indicator light (NE-7920 and NE-7920C)
or stage indicator light (NE-8020) stops blinking
but stays it.
(C) Power relay stops functioning.
(D) Oven tight remains on.
(E) Fan motor and turntable stop rotating.
(F) As soon as the door handle button is pressed, the
short switch contacts close and create the short
circuit.
(G) If the contacts of latch switch A and the contacts of
latch switch B both malfunction, the 15 A fuse
blows open due to the large current surge caused by
the short switch activation, and this in turn stops
magnetron oscillation.
HIGH-VOLTAGE
TRANSFORMER
15A LATCH POWER LATCH
FUSE SWITCH A RELAY SWITCH B
Fig. 12
5. When Reset/Stop pad is tapped once during cooking.
(A) The digital programmer circuit cuts the voltage
supplied to the power relay coil causing the mag-
netron to stop oscillation.
(B) Power indicator light (NE-7920 and NE-7920C) or
Stage indicator light (NE-8020) stops blinking and
stays on.
(C) Oven light turns off,
(D) Fan motor and turntable stop rotating.
NOTE:At this moment, the oven is in “hold’’ condition
and when the start pad is touched again, the oven
starts to operate as originally programmed.
6. When Reset/Stop pad is tapped twice during cooking.
(A) The digital programmer circuit cancels al! instruc-
tions given.
(B) Power relay stops functioning to stop magnetron
oscillation.
(C) Any indications displayed during cooking turn off
and display shows TOD.
(D) Oven light turns off.
{E) Fan motor and turntable stop rotating.

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO
AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY
(A)
Do
not
operate
or
allow
the
oven
to
be
operate
with
compartments,
check
the
magnetron,
wave
guide
or
the
door
open.
transmission
line,
and
cavity
for
proper
alignment,
(B)
Make
the
following
safety
checks
on
all
ovens
to
integrity
and
connections.
be
serviced
before
activating
the
magnetron
or
other
(D)
Any
defective
or
misadjusted
components
in
the
microwave
source,
and
make
repairs
as
necessary
:
interlock,
monitor,
door
seal,
and
microwave
(1)
Interlock
operation
generation
and
transmission
systems
shall
be
re-
(2)
Proper
door
closing paired,
replaced,
or
adjusted
by
procedures
de-
(3)
Seal
and
sealing
surfaces
(arcing,
wear,
and
scribed
in
this
manual
before
the
oven
is
released
other
damage)
to the
owner.
(4)
Damage to
or
loosening
of
hinges
and
latches
(E)
A
microwave
leakage check
to verify compliance
(5)
Evidence
of
dropping
or
abuse
with
the
Goverment
performance
standard
should
(C)
Before
turning
on
microwave
power
for
any
service
be
performed
on
each
oven
prior
to
release
to
the
test
or
inspection
within
the
microwave
generating
owner.
CAUTIONS TO BE OBSERVED WHEN TROUBLESHOOTING
Unlike many other appliances, the microwave oven is high-voltage, high-current equipment. Though it is free from danger
in ordinary use, extreme care shoud be taken during repair.
| CAUTION |
SERVICEMEN
SHOULD
REMOVE
THEIR
WATCHES
WHENEVER
WORKING
CLOSE
TO
OR
REPLACING
THE MAGNETRON.
4. Check the grounding
Do
not
operate
on
a
2-wire
extension
cord.
The
micro-
variasle
|
~——llll/
wave
oven
is
designed
to
be
used
when
grounded.
It
is
imperative,
therefore,
to
make
sure
it
is
grounded
properly
before
beginning
repair
work.
2.
Warning
about
the
electric
charge
in
the
high
voltage
capacitor
For about 30 seconds after the oven stops, an electric
charge
remains
in
the
high
voltage
capacitor.
When
replacing
or
checking
parts,
short
between
oven
chassis
and
the
lower
terminal
of
variable
power
switch
by
an
insulated screw driver to discharge.
See figure 13.
Fig. 13
THERE IS HIGH-VOLTAGE PRESENT, WITH HIGH-CURRENT CAPABILITIES IN THE CIRCUIT) OF THE
HIGH VOLTAGE TRANSFORMER SECONDARY AND FILAMENT TRANSFORMER SECONDALY’. IT IS
EXTREMELY DANGEROUS TO WORK ON OR NEAR THESE CIRCUITS WITH THE OVEN ENIRRGIZED.
NEVER TOUCH ANY CIRCUIT WIRING WITH YOUR HAND OR INSULATED TOOL DURING OPIRZATION.
A114

3.
When
parts
must
be
replaced,
remove
the
power
plug
from
the
outlet.
4.
When
the
15
Amp
fuse
is
blown
due
to
the
operation
of
short
switch:
(A) Replace the latch switch A (primary), latch switch
B (secondary) and short switch. This is mandatory.
Refer to pages 19 & 20 for the necessary adjust-
ments for these switches.
(B) When replacing the fuse, confirm that it has the
appropriate rating for this model.
5.
Avoid
inserting
nails,
wire,
etc.
through
any
holes
in
the
unit
during
operation.
Never insert a wire, nail or any other metal object
through the lamp holes on the cavity or any other
holes or gaps, because such objects may work as an
antenna and cause microwave leakage.
6. Confirm after repair
(A) After repair or replacement of parts, make sure that
the screws of the oven, etc. are neither loose nor
missing. Microwaves might leak if screws are not
properly tightened.
(B) Make sure that all electrical connections are tight
before inserting the plug into the wall outlet.
(C) Check for radiation leakage, (Refer to procedure
for measuring radiation leakage on pages 21 & 22)
DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE
1. Removal of outer panel
Remove
the
four
screws
from
the
front
section
and
seven
screws
from
the
rear
section.
The
outer
panel
must
now
be
pushed backward to be lifted off.
2. Replacement of the magnetron
SERVICEMEN
SHOULD
REMOVE
THEIR
WATCHES
WHENEVER
WORKING
CLOSE
TO
OR
REPAIRING
THE
MAGNETRON.
(A)
Discharge
the
high
voltage
capacitor
(see
page
14)
(B)
Remove
the
air
guide
A
by
removing
2
screws
holding it to the oven cavity.
(C)
Remove
two
high
voltage
leads
from
filament
terminals.
(D)
Remove
two
screws
holding
thermal
cutout
to
magnetron.
(E) Remove four nuts holding the magnetron.
NOTE 1: Make sure that the embossed ring is rigidly
attached on the magnetron anode. (see
fig. 15)
NOTE 2: To prevent microwave leakage, tighten the
mounting nuts properly making sure there is
no gap between the waveguide and the
magnetron.
THERMAL
CUTOUT
Fig. 14
MAGNETRON
Fig. 15
3. Replacement of the fan motor assembly.
(A) Remove the variable power switch and the high
voltage capacitor.
(B) Remove the rubber belt from pulley C.
(C) Remove 5 screws holding fan motor bracket.
(See figure 16 & 17)
(D) Pull the fan motor with the bracket and gear box
toward you.
(E) Remove the belt A from fan motor’s pull ey.
(F) Remove three screws holding the fan motor assern-
bly. (See figure 18)
(G) Remove the wire pin to remove pulley.

NOTE:
When
installing
pulley
A
to
the
shaft
of
the
fan
motor,
pulley
A
should
be
positioned
over
the
hole
on
the
shaft
end
and
then
insert
the
wire
pin.
FAN MOTOR vt
i
i (GH-VOLTAGE, F
VARIABLE
POWER
SWITCH
Fig. 16
Fig. 18
4.
Replacement
of
the
digital
programmer
circuit
(D.P.C.)
for
NE-8020
NOTE‘Be
sure
to
ground
any
static
electric
charge
in
your
body
before
handling
the
digital
pro-
grammer
circuit.
(A)
Disconnect
10-pin
connector
and
plastic
connector
of
tow
voltage
transformer.
(B)
Unsolder
two
lead
wires
connected
to
the
two
inside
terminals
on
the
humidity
sensor.
(Fig.
20)
NOTE:
A.
When
replacing
the
digital
programmer
circuit,
you
must
unsolder
the
two
wires
from
the
humidity
sensor.
Never unsolder the wires from the digital pro-
grammer circuit board itself.
B.
When
reconnecting
the
two
wires
to
the
humid-
ity
sensor,
follow
the
wiring
of
the
sensor
on
page
11
of
this
service
manual.
(C)
Remove
three
screws
holding
the
escutcheon
base
to
the
oven
chassis
(See
fig.
19
}.
(D)
Remove
8
screws
holding
the
digital
programmer
circuit
to
the
escutcheon
base.
NOTE:
Before
installing
a
new
DPC
into
the
oven
es-
cutcheon
base,
you
must
remove
the
two
screws
holding
the
low
voltage
transformer
to
the
PCB
during
shipping.
In
addition
you
must
reinstall
these
same
two
screws
into
the
defective
PCB
to
hold
the
low
voltage
transformer.
This
will
prevent
any
damage
to
the
PCB
during
shipping.
Fig. 19
SENSOR ELEMENT
Fig. 20

DIGITAL
PROGRAMMER
CIRCUIT
1-35 — re
aan BiG
LOW VOLTAGE
TRANSFORMER
Fig. 21
5.
Replacement
of
the
digital
programmer
circuit
for
NE-7920
and
NE-7920C
NOTE:Be
sure
to
ground
any
static
electric
charge
in
your
body
before
handling
the
digital
pro-
grammer
circuit.
(A)
Disconnect
10-pin
connector
and
the
plastic
con-
nector
of
low
voltage
transformer.
(B)
Unsolder
two
lead
wires
connected
to
the
two
inside
terminals
on
the
humidity
sensor.(Fig.
23)
NOTE:
A.
When
replacing
the
digital
programmer
circuit,
you
must
unsolder
the
two
wires
from
the
humidity
sensor.
Never
unsolder
the
wires
from
the
digital
pro-
grammer
circuit
board
itself.
B.
When
reconnecting
the
two
wires
to
the
humidi-
ty
sensor,
follow
the
wiring
of
the
sensor
on
page
11
of
this
service
manual.
(C)
Remove
three
screws
holding
the
escutcheon
base
to
the
oven
chassis
(See
fig.22).
(D)
Remove
7-pin
connector
from
the
membrane
switch
assembly.
(E)
Remove
6
screws
holding
the
digital
programmer
circuit
to
the
escutcheon
base.
(See
fig.24).
NOTE:
Before
installing
a
new
DPC
into
the
oven
es-
cutcheon
base,
you
must
remove
the
two
screws
holding
the
low
voltage
transformer
to
the
PCB
during
shipping.
In
addition
you
must
reinstall
these
same
two
screws
into
the
defective
PCB
to
hold
the
low
voltage
transformer.
This
will
prevent
any
damage
to
the
PCB
during
shipping.
Fig. 22
SENSOR ELEMENT
Fig. 23
DIGITAL
2
LOW VOL_TAGE
TRANSIORMER
Fig, 24
BS

6.
High
voltage
circuit
wiring
Two
types
of
high
voltage
diodes
will
be
used
in
the
high
voltage
wiring.
These
wirings
are
shown
in
figures
below.
WIRING A
\ HIGH-VOLTAGE
CAPACITOR
VARIABLE POWER
SWITCH
HIGH-VOLTAGE
TRANSFORMER
Fig. 25
VARIABLE POWER
HIGH-VOLTAGE SWITCH
CAPACITOR
CHASSIS HiGH-VOLTAGE
TRANSFORMER
Fig. 26
When ordering a diode (ANE6202-C90), you will
receive either an A type or B type diode for your
order. If you receive a different type from the de-
fective one, change the high voltage wiring as shown
in above figures.
7. Replacement of the door assembly.
(A) Remove the 4 bolts holding the upper hinge and
lower hinge to the oven assembly.
(B) Open the door and while pulling the door toward
you, work the upper hinge out through the hole
in the oven assembly. The door will be simply lifted
off the bottom hinge pin at the same time.
(C) When mounting the door assembly to the oven
assembly, be sure to adjust the door assembly
parallel to the sash by moving the upper hinge and
lower hinge according to the directions in fig.27.
Also adjust so that the door has no play between
the inner door surface and oven frame assembly.
lf the door assembly is not mounted properly,
microwaves may leak from the clearance between
the door and the oven.
B4
Fig. 27
Fig. 28

MEASUREMENTS AND ADJUSTMENTS
NOTE: Please note this model has no test resistor for measuring diode or anode current. When you check the high voltage
Circuit, follow the procedure in the troubleshooting guide on page 24.
§ WARNING §
FOR
CONTINUED
PROTECTION
AGAINST
RADIATION
HAZARD,
REPLACE
ONLY
WITH
IDENTICAL
REPLACEMENT
PARTS
(PART
NO.
ANE6142-780,
TYPE
NO.V-15-3C28
FOR
LATCH
SWITCH
A
AND
B
AND
PART
NO.
ANE6158
B60AP,
TYPE
NO.
V-5-3C244
FOR
SHORT
SWITCH).
WHEN
THE
15
AMP
FUSE
IS
BLOWN
DUE
TO
THE
OPERATION
OF
SHORT
SWITCH,
YOU
MUST
REPLACE
LATCH
SWITCH
A,
LATCH
SWITCH
B
AND
SHORT
SWITCH
THEN
FOLLOW
THE
ADJUSTMENT
PROCE-
DURES BELOW.
1. Adjustment of latch switch A (primary)
(A) Mounting of the latch switch to the door hook.
Mount latch switch A to the door hook assembly by
securing the screws as shown in fig. 29 & 30.
Door hook
assembly
Fig. 29
(B)
Installation
of
the
door
hook
assembly
to
the
oven
assembly,
When mounting the door hook assembly to the oven
assembly, be sure to adjust the door hook assembly
by moving in the arrow direction so that the oven
door will not have any play in it.
Check for play in the door by pulling on the door
NOTE:No specific adjustment during installation of
latch switch-A to the door hook is necessary.
Latch switch A
Fig. 30
handle without pushing the handle’s latch button.
Make sure that the latch key positions correctly
during adjustment. Also make sure that the latch
key moves smoothly after adjustment is completed.
Completely tighten the screws holding the door
hook assembly to the oven assembly.
Latch switch A
Door hook assembly
Oven surface
Fig. 31

2.
Adjustment
of
latch
switch
B
(secondary),
short
switch
and
oven
lamp
switch
(A)
Mounting
of
latch
switch
B,
the
short
switch
and
oven
lamp
switch
to
the
door
hook
assembly.
Latch
switch
B,
short
switch
and
oven
lamp
switch
are
installed
onto
the
door
hook
assembly
as
shown
in
fig.32
NOTE:No
specific
adjustment
during
installation
of
latch
switch
B,
the
short
switch
and
oven
lamp
switch
to
the
door
hook
is
necessary.
Oven lamp switch
2return springs
Latch switch B
CI
Y . Actuating lever
LZ,
Gi
<|com
Short switch
Door hook
assembly
Fig. 32
(B)
Installation
of
the
door
hook
assembly
to
the
oven
assembly.
Adjust
the
door
hook
by
moving
it
in
the
direction
of
arrow
in
fig.
33
so
that
the
oven
door
will
not
have
any
play
in
it.
Check
for
play
in
the
door
by
pulling
on
the
door
handle
without
pushing
the
handle’s
latch
button.
Make
sure
that
the
latch
key
moves
smoothly
after
adjustment
is
completed.
Completely
tighten
the
screws
holding
the
door
hook
assembly
to
the
oven
assembly.
Latch key =|
Fig. 33
3.
Measurement
of
the
magnetron’s
output
The
power
output
of
the
magnetron
can
be
measured
by
performing
a
simple
water
temperature
rise
test.
Equipment needed for the Test:
*Two 1 liter beakers
* One glass thermometer
B6
NOTE:
Check
the
line
voltage
under
load.
Low
voltage
will
lower
the
magnetron
output.
Make
allt
temperature
and
time
tests
with
accurate
equip-
ment.
(A)
Fill
the
two
1
liter
beakers
with
water
and
mark
one
A
and
one
B.
(B)
Stir
the
water
in
each
beaker
with
the
thermometer
and
record
each
beaker’s
temperature.
Beaker
A’s
temperature
=
T1A
Beaker
B's
temperature
=
T1B
(C)
The
average
value
(T1)
of
T1A
and
T1B
is calcu-
lated
as
follows:
Tie TIA su B
(D) Place both beakers on the center of the glass cook
plate.
Set the oven for High power and set two minutes.
Heat the water for exactly two minutes.
(E) When the heating is finished, again stir the water
with the thermometer and measure the temperature
rises as T2A and T2B.
(F) The average value (T2) of T2A and T2B is calcu-
lated as follows:
T2= T2A a
(G) Subtract T1 from T2. This will give you the tem-
perature rise.
(H) The normal temperature rise for this model is 16°
to 20 F (8.9 to 11 C) at the ‘‘High’’ power selec-
tion.
*If no temperature rise is noted, refer to the
“TROUBLESHOOTING GUIDE"