Panasonic PT-302 User manual

ORDER NO. VED86100027C3
ervice Manual
Colour Video Projector
PT-302
chassis No. Q5
The service technician is required to read and follow the ‘‘Safety Precautions’ and ’’Important Safety Notice” in this
service manual.
Specifications
Power Source: AC 220V ~ 240V, 50/60 Hz 4318 mm (170 inch) Picture size:
Power Consumption: 179W (average) 5102 mm (200 7/8 inch)
Projection T ube: 7 inches (179 mm) specially developed 5080 mm (200 inch) Picture size:
High-Brightness liquid cooled 5963 mm (234 3/4 inch)
CRTs (R, G, B). 6350 mm (250 inch) Picture size:
Lenses: Double Focus, Three F 1.0 145 7400 mm (291 11/32 inch)
Lenses (HYBRID) 7620 mm (300 inch) Picture size:
Resolution: Video...... 650 TV Lines (typical) 8835 mm (345 27/32 inch)
RGB........ 1000 TV Lines (typical) Light Flux: 500 lumens (typical) at white peak
Video Input Level: 140.3Vp-p 75Q Operating Ambient
Line in/out Level: 1+0,3Vp-p 75Q or high impedance Temperature: 32°F ~ 104°F (0°C ~ +40°C)
RGB Input Level R: 0.74+0.3Vp-p 752 Operating Ambient
G: 0.7+0.3Vp-p 75Q Humidity: 20% ~ 80%
(GSYNC: 140.3Vp-p 75Q) Supplied Accessories: AC Cord (3 types)
B: 0.7+0.3Vp-p 75 Mounting kit (1 set)
H/HV: 0.3 ~ 6V, high impedance Dimensions: Height: 290 mm (11 13/32 inch)
V: 0.3 ~ 6V, high impedance Width: 576mm (22 11/16 inch}
Screen Size: 3810 ~ 7620 mm (150 ~ 300 inch) Depth: 606 mm (23 29/32 inch)
Throw Distance: 3810 mm (150 inch) Picture size: Weight: 77 \|bs. (35 kg)
4528 mm (178 1/4 inch)
; Specifications are subject to change without notice.
Weight and dimensions shown are approximate.
a
rs Fy
5
Panasonic
Matsushita
Elecite
Weds
Co.

PT-302
CONTENTS
FEATURES oc. o's Sys ase 8 ad Reece che erarae Beddacs ar ahaa Ay. eee a eee RO oes ee A 2
SAFETY PRECAUTIONS 225.25 iecce Sie 5 ata ela alee le esti ee tee as Wwe Gee a Ste 9 She 3
LOCATION OF CONTROLS, OPERATIONS AND
CONNECTION OPTIONAL EQUIPMENT........... 0.00 cue ue c ences 4~8
DISASSEMBLY INSTRUCTIONS ........... 00. ccc cere eee ne eres 9,10
MAIN PARTS LOCATION CHART .......... 0... cc cece cece ee tee ere eens 11
CAUTIONS FOR SERVICING ......... 0... ccc ee ee eee eens 12,13
FIELD ADJUSTMENTS. ..... 2... .. eee e ee eee eee eee eee eee ane 14 ~20
INSTALLATION/ADJUSTMENT PROCEDURE ..............0 000 ec ucuae 21 ~ 32
LOCATION OF TEST POINT AND CONTROLS ............ 00 veer e eee eee 33 ~ 35
BLOCK DIAGRAM). 6.5.4.0 6-06 eee g ow be Ses COS Se EO Hews Gee Rae 36 ~ 38
INTERCONNECTION... 0... 0... cc cee eee eee ee ee eee eee ee eee 39, 40
TERMINAL GUIDE OF IC’S, TRANSISTOR AND DIODES. ..............0 0000 ae 41
CIRCUIT: BOARD i oie: oa hia ish ae. hb Gee ie ee SPR ew le Ge Oe bala wee 42 ~ 54
SCHEMATIC DIAGRAM ......... 0.0. ecw ee ee ee eee eee anaes 55 ~ 74
F/K/P/Q/V/X-BOARD Sections. ......... 0.00 cece eee ee eee eee ee ees 57, 58
M-BOARD Section ....... 0.0... ce eee eee ewe eee ee eee eens 59, 60
B/S/LR/LG/LB-BOARD Sections... .......... 00 cc eee uceceucuveees 65 ~ 68
C/J/TR1/TR2-BOARD Sections... 2.2... 0.0... cece ee eee ee 69 ~ 71
A/G/R/T-BOARD Sections... 0.0... 0... cece ee ee et eee eee 72 ~74
EXPLODED: VIEWS en. 5: ees cece ese el a a ote eae eae eee. AS. rete bl ce 75 ~ 80
TROUBLESHOOTING. .... 0.0... cece ccc eee eee te eee 81, 82
REPLACEMENT PARTS LIST... 0... .. eee ee ee eee eee ees 83 ~ 110
FEATURES
1 Superb bright picture: High luminance output: 5 Improved raster quality:
500 lumens (typical) at white peak High voltage regulation characteristic: 0.3 MQ
2 Superb resolution: 1000 Lines (RGB) (typical) 6 eee installation and front/rear projection easily
selectable.
650 Lines (Video) (typical)
RGB character reproduction:
e Ceiling mount/front projection
e Ceiling mount/rear projection
equivalent to 2000 characters e Floor placement/front projection
(80 x 25) e Ceiling mount rear projection with mirror
3 Compact size and light weight (35 kg, 77 Ibs), for easy ¢ Floor placement rear projection with mirror
7 Wide-range computer compatibility
placement/installation.
aor . : . : 8 Four broadcast system capabilit
4 Compatibility with various signal input sources: sys Spe arty
PAL, SECAM, NTSC and M-NTSC 4.43
VTR/VCR Video Disk
Video Camera RGB Computer
TV Tuner

SAFETY PRECAUTIONS
GENERAL GUIDELINES
1. It is advisable to use an isolation transformer in the AC
line supply before servicing this model.
2. When servicing observe the original lead dress, especially
in the high voltage circuit. In case of a short circuit,
replace every part which has overheated.
3. After servicing observe that all protective devices such as
insulation barriers, fish paper, shields, isolation networks
and fuses are properly installed.
4. Before turning the receiver on, the resistance between
the B+ line and chassis ground should be checked.
Connect the © side of an ohmmeter to the B+ line and
the @ side to chassis ground.
Each line should have more resistance than specified,
as follows:
B+ (B—) Line Minimum Resistance
206V 10kQ
116V 3kQ.
27V 30022
17V 2002
12V 10022
10V 3Q
* -17V 150Q
* — Side to ground
5. If the set is not intended to be used for a long time, the
power cord should be unplugged from the AC line outlet.
6. Potentials, as high as 32.5 kV are present when this
set is in operation. Removal of the covers involves the
danger of a shock hazard from the set’s power supply.
Servicing should not be attempted by anyone who is not
thoroughly familiar with the precautions necessary when
working on high-voltage equipment.
Always discharge the anode of the projection tube to
the set chassis before handling the tube.
7. After servicing, make the following leakage current
checks to prevent a shock hazard.
LEAKAGE CURRENT COLD CHECK
1. Unplug the AC cord and connect a jumper between the
two plug prongs.
2. Turn on the set.
3. Measure the resistance value with an ohmmeter between
the jumpered AC plug and each exposed metallic part
such as screwheads, input terminals, control shafts, etc.
When the exposed metallic part has a return path to the
chassis, the reading should be between 490 k{2 and
9 M&2. When the exposed metal does not have a return
path to the chassis, the reading must be infinite. —_
PT-302
LEAKAGE CURRENT HOT CHECK (See Fig. 1)
I
Plug the AC cord directly into the AC outlet. Do not
use an isolation transformer for this check.
. Connect a 2 kQ, 10W resistor, in series with an exposed
metallic part on the receiver and an earth such as a
water pipe.
. Use an AC voltmeter, with 1000 ohms/volt or more
sensitivity, to measure the potential across the resistor.
. Check each exposed’ metallic part, and measure the
voltage at each point.
. Reverse the AC plug in the AC outlet and repeat each of
the above measurements.
. The potential at any point should not exceed 1.4 volts
RMS. _ In case a measurement is outside of the limits
specified, there is a possibility of a shock hazard, and the
receiver should be repaired and rechecked before it is
returned to the customer.
HOT- CHECK CIRCUIT
AC VOLTMETER (High Impedance)
TO WATER PIPE
INSTRUMENT ’S 2kn, LOW J (EARTH)
EXPOSED
METALLIC PARTS
Fig. 1
X-RADIATION
WARNING: | The potential source of X-Radiation in the
color Projection System is the High Voltage
section and the projection tubes.
NOTE: it is important to use an accurate, peliodically,
calibrated high voltage meter.
1. Turn the Brightness control fully counterclockwise.
. Measure the High Voltage. The high voltage meter
should indicate 32 kV + 0.5 kV. If the upper meter
indication is out of tolerance, immediate sevice and
correction is required to prevent the possbility of
premature component failure. (Refer to hich voltage
adjustment in the manual.)
. TO prevent an X-Radiation possibility, it ig esen tial to
use the specified projection tube only.
. To prevent exposure to X-Radiation, the groy ection
tube shield must be kept in place with power ap lied to
the set.
WARNING: When using a projection tube tet jig for
service, ensure that jig is capable otha Nndling
32.5 kV without causing X-Radiati«n.

PT-302
LOCATION
OF
CONTROLS,
OPERATION
AND
CONNECTING
OPTIONAL
EQUIPMENT
LOCATION OF CONTROLS
AC IN
MAIN POWER SWITCH
IMPEDANCE SELECTOR SWITCH
LINE IN/OUT TERMINAL
VIDEO INPUT TERMINAL
G/EXT
SYNC
SELECTOR
SWITCH
V
INPUT
TERMINAL
H/HV INPUT TERMINAL
B INPUT TERMINAL
G/G SYNC INPUT TERMINAL
R INPUT TERMINAL
BLUE SELECTOR
@prower SWITCH
SWITCH
TV SYSTEM
SELECTOR
SWITCH
COLO
R
CONTRAST
SHARPNESS
OPERATION
TO
Operate
the
projector
switches
@
and
@
must
be
turned
ON,
and
switch
@
must
be
set
to
the
proper
input
signal
type.
Note:
When
the
separately
supplied
remote
controller
(ET-12R)
is
connected
to
the
video
projector,
switches
@
through
@
and
@
through
@ are
inoperable.
Please use
the
remote
controiller
for these
functions.
= AS

Switch. PURPOSE
MAIN POWER
SWITCH
OFF BL = ON Switches main power supply ON/OFF.
MAIN POWER
Power ON/OFF switch.
POWER SWITCH
REMOTE BH = ON This switch is set to the OFF position, when the remote control
is in use.
RGB LINE VIDEO VIDEO---Push this button to view signals input via the VIDEO
input terminal.
LINE ---Push this button to view signals input via the LINE
input terminal.
RGB_---Push this button to view signals input via the RGB
INPUT SELECTOR input terminal.
INPUT SELECTOR
SWITCHES
This switch is operable only when RGB signals are being re-
NORMAL . a ceived. Use this switch when the blue portion of the picture is
weak.
FINE BLUE + NI) NORMAL ---Normal blue.
BLUE MONO- FINE BLUE -:--A finer , easier-on-the-eye, blue.
BLUE MONO:-:--White picture on a blue back ground.
Note: When Linear or TTL RGB signals are input at inappro-
BLUE
SELECTOR
priate
levels,
the
FINE
BLUE
and
BLUE
MONO
modes
might not operate properly.
BLUE SELECTOR
SWITCH
SECAM , This switch is normally set at AUTO.
PAL. i i ity i
TV SYSTEM igre: eiedel if the isk eae bad . the use of dubbed
SELECTOR SWITCH Nee: pes, etc., reception may not be satis ac ory.
AUTO * In that case, set the switch to the appropriate input signal using
a screwdriver.
SYSTEM
The click-stop indicates standard, brightness.
=== (y EDO Adjust to the appropriate brightness level for current viewing
- conditions.
Decrease Increase
EC ds Adjust to a desirable color intensity.
Decrease Increase
E=0 ==) Es. To obtain a sharper picture rotate the control clockwse.
For a softer picture rotate the control counter-clockwse.
soft sharp
|
EC
DO0-
Adjust
to
a
comfortable
viewing
level,
a
slightly
less
iniense
Low High picture is easier on the eyes.
Color Color
0 eB Adjust for proper skin tone.
red gree
If the picture rolls, as shown, adjust
E) ED ttre contro uP or DOWN until it
UP DOWN stabilises.
Sh

PT-302
CONNECTING OPTIONAL EQUIPMENT
Connect optional equipment (example) according to following illustration.
CASE 1: Connection to a video source —_—TV Monitor
Video Projector
HIZ M0750
VIDEO IN aa
eT
Video
Camera
Hifi VCR
beveneaienenenene 2 es |
TV Tuner
PERSONAL COMPUTER
RGB INTERFACE (optional)
ET-11G/12G
=
—
SELECT THE
APPROPRIATE
SYNC TYPE
G. G/SYNC

CASE 3: Connection to the remote controller ET-12R (optional)
REMOTE CONTROLLER (optional) hee
ET-12R
ERTAMIPILIER
Presentation System
This is the most orthodox VTR playback
system. Various variations can be de-
veloped on this system according to the
required applications.
Applications:
®@ Conference Rooms
® Classrooms
@ Public Areas
REMOTE IN
Note:
The PT-302 operates on positive or
negative SYNC. The SYNC inverting
switch is factory preset to the ‘““NOR-
MAL” position for negative SYNC.
For positive SYNC set the switch to the
“REVERSE” position.
During installation set the SYNC invert
switch for the appropriate SYNC polarity.
~#—_
REMOTE
CONTROL
CABLE
(opticonal)
ET-11C15.......
ET-11C30.......
ET-11C50.......
50 feet (15 m)
100 feet (30 m)
164 feet (49.5 m)
GRRE EE
Entertainment System 1
This system is ideal for use for parties,
ceremonies, etc. to’ be held in large
places. Great effects are possible with
the powerful video images from colour
video projectors, when combined with
video cameras and audio equipment.
Applications:
@ Banquet Halls
@ Lounges Discos
Video Camera
aaa
1
Remote Control _ Monitor
Unit
Effects
AV Switcher
Controller
Monitor Microphone
[ ¥y 7 ---
aa
Es
Controller
Audio
Mixer
Amp
- Monitor Pa
i = i Wireless
Microphone
Tuner Wireless Amp
ERSTAIMIPILIERS
Business Application
This system is designed to concentrate
on data presentations for business, con-
ferences, showrooms, etc. Its superb re-
solution and capacity to match various
types of personal computers make it ideal
for upgrading office-automation systems
and diversifled video/data services.
Applications:
® Conference Rooms
@ Training Areas
@ Information Displays
ae I en HO
Video Projector
-————__——]
7 feos]
[ ¥ Special
Video Camera _ Monitor
Generator AV Switcher
Gal Sa — Pcl Screen
Hi-Fi VTR Monitor Video polices
ene
grttctt
His
T
ee oe
ices cea
v
ae
Had Vo
'
t
!
VTR !
rr en
i
j
7 Video Projector
i
i
I
OM eR Hm Mtn SHOE RON ONG nl en nenpncenteeon omen
:
RGB Interface ——
Computer ~T |
Be cece enw ae eer rannsieramanraes
crane
BREE EE &
Entertainment System 2
This system is particularly suited to such
recreational facilities as bars, restaurant,
dance clubs, etc. A wide variety of atmos-
pheric effects can be produced. When
used together with stereo sound, a re-
laxed aura of “background video“ and
“mood” music, or dynamic video images
with music with a beat to match.
Applications:
@ Lounges Discos
@ Restaurants
Hi-Fi VTR
Monitor
Controller
Hi-Fi VTR
r-
U
!
Monitor '
Controller a
a a eer 1
‘
—[ J O
Monitor Microphone Turntable
a a
ERIAIMPPILIERS
Educational System
Ideal for a wide range of educational acti-
vities, particularly as an effective teaching
aid.
Applications:
@ Classrooms
® Auditoriums
@ Lecture Halls
Screen
{ Video Projector
Ce
| AV Switcher =
reas)
rot
Jt
Audio Mixer Amp
PT-302
rv
t
1
-~ eall--!
Microphone
AV Switcher
aay
[
=
|
Video shea ctor

PT-302 PT-302
DISASSEMBLY INSTRUCTIONS 5) “G”-Board 5. HOW TO REMOVE THE PROJECTOR TUBE
1. HOW TO REMOVE THE TOP COVER 4, HOW TO OPEN THE PRINTED CIRCUIT BOARD © Remove 2 screws @ in fig. 8. (WHEN RED)
1) Open the cover of control panel. 1) Cand D, V-Boards @ Then pull the G"-Board toward the back side of 1) Remove the two retaining 2 screws (L) from the tube
2) Remove 3 screws () in fig. 2. @ Loosen 2 screws ©) to counterclockwise by 90° in the deck, and carefully lift it to open the 'G” Board. shown in fig. 12.
3) Then pull the Top Cover toward the back side of the fig. 5. 2) Remove the lens grill shown in fig. 3. (Remove 4 screws
deck and carefully lift it for removal. @ The lift the rear of the chassis to open the “C",- ®).
3) Remove the anode lead @) from the high voltage
distributor shown in fig, 13.
4) Remove the LR printed circuit board (N) in fig. 13.
5) Remove the retaining screw of the neck shield ©) and
“D" V-Board.
D-Board-7”
M-Board
3
screws
2
screws
G-Board
remove
the
neck
shield
©
in
fig.
13.
w
@
(3)
6)
Remove
the
retaining
screw
of
the
deflecting
coil
@
Fig.
8
and draw
out
the
centering
magnet
®
and
the
diflecting
Cover
of
6)
“K’’-Board
coil
S)
in
fig.
13.
<
control
panel
@
Remove
the
Front
Panel.
7)
Remove
the
grounding
lead
from
the
tube.
@
Then
carefully
pull
and
lift
the
Terminal
Panel
for
8)
Remove
the
4
retaining
screws
@® from the
tube
and
removal
in
fig.
9.
draw
it
out
shown
in
fig.
14.
@
Remove
2
screws
(1)
in
fig.
10.
2)
“A’
-
“B"-Boards
@
Then
lift
and
pull
out
the
““K’'-Board.
@
Remove
a
1
screw
©
in
fig.
6,
and
remove
the P.C-Board fixing metal.
Fig. 2 @ Then carefully pull and lift the ‘A’ and B” Boards
for removal.
2. HOW TO REMOVE THE LENS GRIL
1) Remove 4 screws in fig. 3.
2)
Remove
the
Lens
Gril.
Terminal
anel
Lens
Gril
pi
P.C Board Fixing Metal
Fig. 6
3) "F’-Board
@ Remove a 1 screw © in fig. 7, then open the F”-
Board.
Fig. 3
3. HOW TO REMOVE THE CONVERGENCE
CONTROL COVER
1) Open the cover of control panel.
7) “P” and ‘‘Q’’-Boards
@ Remove the Front Panel! and Terminal Panel.
@ Remove 2 screws YQ) in fig. 10.
@
Remove
4
screws
()
in
fig.
11,
and
lift
the
box
cover.
4
screws
(T)
@
Then
open
the
‘’P”’
and
‘‘0’'-Boards.
ee
2) Remove a1 screw ©) in fig. 4.
3) Then pull the Convergence Control Cover toward the
control panel side for removal.
Cover of Convergence Box cover
control panel control cover
1 screw ©
Fig. 7
4) “M"-Board
@ Remove 3 screws @) in fig. 8.
@ Then pull the ‘’M’’-Board toward the back side of
the deck, and carefully lift it to open the ‘‘M"’-Board.,
Fig.
4
Fig.
14

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Fig. 15

PT-302
CAUTIONS FOR SERVICING
HORIZONTAL OSC. DISABLE CIRCUIT TEST REPAIR PROCEDURES OF THE HORIZONTAL
This test must be made as a final check before the set is OSCILLATOR DISABLE CIRCUIT
returned to the customer. 1. Connect a DC voltmeter between capacitor C1413 +
1. With the chassis case removed, supply a nominal 120V on the D-PCB and chassis ground. If approximately
AC to the set, and turn the set on.. 150V is not present at that point find the cause. Check
2. Set the customer controls to normal operating positions. R535, R591, R1430, R534, C1413 and D1408.
3. Locate Q1404 and short it’s collector to the emitter 2. Connect a DC voltmeter between capacitor C518 + on
with a jumper wire. Confirm that this shorts the high the C-PCB and chassis ground. C518 + potential varies
voltage and that the raster disappears. from nearly OV approx to nearly 4V approx when
4. |f this does not occur, the Horizontal Osc. Disable shorting Q1404 (C-E). If this does not occur, find the
Circuit is not operating. Follow the Horizontal Oscil- cause. Check R530, R531, R537, R538, R539, R540,
lator Disable Circuit Repair Procedures before the set is R541, R542, R543, R544, C513, C518, C519, C520,
returned to the customer. D507, 0510, Q511 and O512.
NOTE: The power on/off switch must be turned off and 3. Carefully check the above specified parts and related
then on to restore operation. circuits and parts. When the circuit is repaired, try the
Horizontal Oscillator Disable Circuit Test again.
4. In case that at least one of R535, R591, R534, D507,
and the FBT is replaced follow the Adjustment Pro-
cedure for the Horizontal Oscillator Disable Circuit as
follows.
+27V
To 1C401
Pin ®
R542 R541
Q511
2SB709A 0.01 D1408 R1430
RvU1 220
R531. +} C513. +] C518 FBT PULSE
Q512
2SD601A QA207M3
—i2-—