Pentax ME Super User manual

PRODUCT No.23900
ASAHI PENTAX
SERVICE MANUAL ENGLISH

23900 Page 1of 15
23900 ME
Disassembly Procedure
1. Self-timer charge lever assembly (0-A118)—Self-timer screw left-handed (A122)
— 231K-H50
2. Body Covering, left and right (A19, A20)
3. Install self-timer lever assembly (0-A118) temporarily.
4. Bottom cover assembly (A400) — CSS 1.7 x 2.8 x 3
Connector seat (A23), R button (C117)
5. Winding lever assembly (0-C69)
Cover screw (C139) — 23600K-C135-A (left handed)
Winding lever nut (C8) — 23600K-C134-A2
Cover ring (A321)
6. Shutter dial
Shutter dial at AUTO
Loosen set screw (A319) — Shutter dial (A316)
Release pin (A313) — Release button (A317)
7. Rewinding knob
R Rewinding knob assembly (0-D6) — Nut (D15) - Washer (D21)
- ASA dial assembly (0-D11-01)
23600k-D4-A2
8. Top cover assembly (A300) - 4 screws - cover frame (A131)
9. Unsolder 12 lead wires and one contact piece
Take out lead wires from cord holder
Lead wire No. 21 (K100), No. 24 (T100), No. 22 and No. 23 (T100),
No. 19 and No. 20 (N4), No. 15, No. 16, No. 17, No. 18 and one
Contact piece (A129), No. 26 and No. 27 (0-A21).
10. ASA volume assembly (R100) - Top cover screw (A16) - CNL-d 1.7 x 2.5
11. Hot shoe contact piece (N4)
12. P.C. board retainer (I1) - W14
13. P.C. board retainer plate (N5) - T-CNS 1.7 x 5
14. LED retainer screw - CNL-D 1.4 x 2 - W31
15. P.C. board assembly (T100)
16. Front board and mirror housing
Cocking the shutter
Removing 5 screws - W14
Shutter light seal cover (A8)
17. Bulb actuator plate (A504) - CNL-D 1.4 x 2
18. Cocked indicator assembly (0-C23)
SW actuator lever shaft (C49)

23900 Page 2of 15
19. Counter dial Back cover open
Counter dial spring (C57) - Counter retainer plate (C25),
Counter dial assembly (0-C34)
Come off transporting claw spring (C65)
Remove (C146) (C53) and CNS 1.7 x 3
Winding seat assembly (0-C2) - (0-C5) - (C7)
20. Shutter block (S000) - CNL-D 1.7 x 3 x 3
21. Bottom release assembly (0-C147)
Winding up little from bottom part with tool (23900K-C207-A)
To remove retainer screws of (0-C147).
22. Release plate assembly (A500)
Guide screw (A507) - Release plate restitution spring (A510).
When removing (A500), detach hook lever (C108) from (A500)
23. Shutter charge lever assembly (0-C129)
Loosening joint (C207) with tool (23900K-C207-A), remove (0-C129)
and (C144).
Fasten joint (C207) again.
24. Winding guide plate assembly (0-C102)
25. R lever assembly (0-C105)
LW-13 - (0-C105) - (C126)
(C145) - LW13 - (C144) - (C107) - (C130) - W14 - (C108) - W8 - (C125)
(C207) - (0-C106) - (0-C12).
26. Back cover assembly (0-C26)
27. Winding stopper assembly (0-C26)
28. Winding shaft assembly (0-C22) - Main gear (C30)
29. Sprocket shaft pin (C40) - Loosening set T 1.7 x 1.6
30. Top mec. Plate assembly (0-C1) - (C146) x 2 - CSS 1.7 x 3
31. Spool cam assembly (0-C202) and spool assembly (0-C204)
- W17 (t=0.2mm)

23900 Page 3of 15
Assembly Procedure
1. Spool assembly (0-C204) and spool cam assembly (0-C202)
W17 (t=0.2mm)
2. Top mec. Plate assembly (0-C1)
Pulling back transport indicator
3. Sprocket shaft pin (C40)
Apply screw lock on Set T 1.7 x 1.6
4. Winding shaft assembly (0-C22) - Main gear (C30)
5. Winding stopper assembly (0-C26)
6. Winding spring assembly (0-C12)
Proper tension of the spring is shown in figure.
After installing (0-C12), install (0-C106) and (C207) temporarily.
- 23900K-C207-A
7. Perforation adjustment - Tool 23102-C57-A
Same adjustment with K2 camera.
Choosing proper 2nd gear (C31).
8. Bottom mechanism
a) (C125) - W8 (t=0.1) - Winding hook lever (C108) - W14 (t=0.05, 0.1) -
(C130) - Winding lever ratchet (C107) - LW13 - (C145)
b) (C126) - R lever assembly (0-C105) - LW13
c) Winding guide plate assembly (0-C102) - (C146) - CSS 1.7 x 2.5 - CNS 1.7 x 3
d) Shutter charge lever assembly (0-C129)
Loosening (C207) - (C144) - (0-C129) - fastening (C207)
When fastening (C207), winding shaft should be in the wound position, at
the same time, mirror charge lever (0-C102) should be moved to a correct
position
9. Shutter release plate
Release plate restitution spring (A510)
(Take care to install spring in correct direction)
Release plate assembly (A5000
(Take care not to bend winding hook lever (C108).)
Guide screw (A507), connection spring (A511)
(Engaging (A510) to (A500).)
10. Bottom release assembly (0-C147) - CNM 1.7 x 2.2, CNM 1.7 x 2.8
Winding shutter a little

23900 Page 4of 15
11. Shutter block (E000) - CNL-D 1.7 x 3 x3
Light seal plate (A8)
12. Bulb actuator plate (A504) Temporary installation
- CNL-D 1.4 x 2
13. Back cover assembly (A200)
14. Winding seat assembly (0-C2) - (C53), (C146), CNS 1.7 x 3
Install (0-C2) with back cover open
Winding lever click cam assembly (0-C5)
Winding lever friction spring (C7)
Engage transporting claw spring (C65)
15. Counter transporting adjustment
a) Check the function of counter dial stopper lever (C4) and transporting
claw assembly (C18).
b) If the vertical black lever of (0-C26) is bent forward, bend it straight.
c) Adjust the counter transporting function using the temporary counter
transporting gear (C34).
When back cover is closed, receiving claw (C16) and transporting claw (C18)
should be engaged to the first tooth of (C34) simultaneously with enough
gearing portion. Bend the tip of the claw which couples with the gear (C34),
If not enough gearing portion.
When back cover is opened, claw tip of (C16) must detach from the gear (C34)
with a clearance of about 0.5mm.
If there is not enough clearance, bend the other end of (C16) opposite from
the claw as shown in the figure.
16. Counter dial
Counter dial assembly (0-C34)
Counter dial spring (C57)
Counter retainer plate (C25)
(C25) is installed in left side gutter as shown in figure.
Give the spring (C57) 1/2 or 3/4 turns of tension.
17. Bulb off adjustment (Winding lever is at pre-advance position.)
After releasing the first curtain, adjust "B" off position with eccentric
screw riveted on bulb actuator plate (A504). When shutter rod comes back,
0.2mm clearance is necessary after releasing the 2nd curtain.

23900 Page 5of 15
18. Cocked shutter assembly (0-C23) - SW actuator lever shaft.
19. Main SW adjustment = (I200)
When shutter actuator plate is held in "ON" position, 0.2mm clearance is
necessary between longer contact piece of main SW and insulation blue
collar.
To adjust the clearance, bend the shorter contact piece.
When both contact pieces touch each other, and the shorter contact piece
is pulled down, the longer one should be down also as the shorter one does.
If there is not enough tension on the longer contact piece, it may show
uneven shutter speed.
When winding lever is at closed position, 0.2mm clearance is necessary
between both contact pieces.
20. Front board and mirror housing
When the above mentioned parts are installed, shutter block (E000) should
be cocked but not charge mirror housing.
Put on W14 (0.1mm) underneath front board and fasten it with (A132),
pushing down left. Confirm the function of self-timer, shutter mechanism
and mechanical back.
21. Parallax adjustment
22. P.C. board pattern assembly (T100)
(I1) - CNL-D 1.7 x 2.5 - (N5) - T-CNS 1.7 x 5 - (N4) - (N6 x 2)
23. ASA volume assembly (R100) - (A16) - CNL-D 1.7 x 2.5
24. Soldering 13 lead wires
25. Bottom cover assembly (A400) - (A23) - (C117)
26. LED positioning adjustment
27. Temporary top cover and installing ASA dial assembly (0-D11-01) and winding
lever temporarily.
28. a) Shutter speed adjustment - VR-A
ASA 100, X1, f8, (KA-00-1A), 2.8V
EV12 - 1/60
EV16 - 1/1000
EV8 - 1/4

23900 Page 6of 15
b) LED indication adjustment
High EV (EV12), EV16) - VR-B
Low EV (EV8) - VR-C
c) Battery checker - VR-D
2.45V - Turning on and off (flickering)
2.55V - Turning on
d) VR-E is prohibited to adjust
29. Counter indication (C15) - (A300)
30. Top cover
(A131) - (A300)
Set shutter dial at "B"
Shutter restriction lever is set at left (viewing from back)
Put on top cover softly and fix it turning shutter dial to AUTO position
Four retainer screws
Rewinding parts, shutter dial, winding lever, etc.
31. Shutter stroke adjustment
a) Set shutter dial at "B"
b) 0.2mm clearance is necessary after releasing shutter.
Adjust the shutter stroke with eccentric screw.
32. X Synchronization with self-timer operation at "B"
When camera is operated with self-timer operation at "B" position,
exposure time should be adjusted around 11~13ms.
To adjust the exposure time, bulb actuator plate (A504) should be moved
up or down with eccentric screw.
Also check shutter dial 100X with self-timer operation in the same manner.
If camera is not adjusted as mentioned above, it is impossible to take
pictures with complete synchronization with electronic flash, especially in
the following combination such as shutter dial at 100X, winding lever at
closed position and with self-timer operation.
33. Focusing

23900 Page 7of 15
34. Body covering, self-timer lever assembly (0-A118)
Self-timer screw (A122) - left-handed.
35. Disassembly of front board and mirror housing
a) Remove self-timer (H000)
b) Mirror release lever (0-A111)
c) Mirror housing
d) Connector (I100) - only loosening (I2)
e) Unsolder 5 lead wires
Purple 2, orange 2, black 1
36. SWg, SWm located underneath mirror housing
SWg = Magnet switch
SWm = Memory switch
a) SWg - Spring tension adjustment
8~10g spring tension is desirable: Check with tension gauge.
b) SWm adjustment
Bend longer contact piece as shown in figure.
Shorter contact piece should have proper tension.
(Check the tension after charging the mirror housing.)
c) SWg adjustment
When mirror housing is charged, 0.2~0.3mm clearance is necessary
between both contact pieces.
Bend longer contact piece as shown in figure.

23900 Page 8of 15
37. Adjustment of SWm and SWg
Time lag sequence of SWm and SWg
To check the time lag, an oscilloscope is necessary.
The time lag is determined by the variation in voltage when
SWm and SWg turn "ON" and "OFF".
Here is one example for time lag check with a single-trace oscilloscope.
Adapter should be made as shown below.
Adapter is connected to mirror housing connector and oscilloscope.
After charging the mirror housing and releasing it to put the mirror in
the "up" state, time lag appears on the oscilloscope screen.
The adjustment procedures can be referred to in item 36.

23900 Page 9of 15
PENTAX ME
Notes and Troubleshooting Tips
FIGURES:
Fig. 1 - Top cover removed
Fig. 2 - Bottom cover removed
Fig. 3 - Front of camera, wind side
Fig. 4 - Front view, mirror box removed
Fig. 5 - Bottom of mirror box
Fig. 6 - Current style, mirror switches
Fig. 7 - Circuit for testing mirror switches
Fig. 8 - Wiring diagrams
Fig. 9 - Modified bottom cover
ADJUSTMENT LOCATIONS:
Auto speeds A Fig. 1
Meter readout, high light B Fig. 1
Meter readout, low light C Fig. 1
Battery test D Fig. 1
Release overtravel E Fig. 3
Mechanical speed F Fig. 4
Travel time, 1st blade G Fig. 4
Travel time, 2nd blade H Fig. 4
Trigger switch (fast speed) I Fig. 4
Magnet switch J Fig. 5
ADJUSTMENT VALUES:
Blade travel time: 6ms (20mm distance)
Flange-focal distance: 45.46mm (flange to film guide rails)
Release overtravel: 0.2mm additional travel of release slide after
shutter releases
Mechanical speed: 11ms to 13ms exposure time when operated with
self-timer action at bulb setting
Battery test: Viewfinder LEDs to light steadily with 2.55V
supplied and to flash on and off at 2.45V
Memory time lag: Magnet switch SWg to close 10ms after memory
switch SWm opens