Pentax Data MX User manual

SERVICE MANUAL

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23800 MX
Disassembly procedure
1. Peel off Body coverings (A19 & A20)
2. Remove Bottom cover (A400), Connector seat (A34) and Tripod screw (All).
CSS 1.7 x 2.2 x 3, CSM 1.7 x 3.5 x 2
3. Remove Top cover (A300)
a.) Retainer screw (Left handed)
Winding lever assembly (C300)
Cover ring B (A329)
b.) Shutter dial— ASA100, 1/1000
Shutter dial screw (E231) — 23800K-E321A
Shutter dial assembly (0-E223), Hook pin (E228)
Speed dial assembly (0-E229)
c.) Knob assembly (0-D1)
Nut (D12)—23110-D16-1-A
Cover ring (D7)
• d.) Top cover retainer screw (A15 x 2)
CSS 1.7 x 2.2 x 2
Top cover assembly (A300)
4. Unsolder 7 lead wires
5. Front board plate assembly (A100)
— Not necessary to cock self-timer.
Cover (A24)
0.1mm washers are underneath the Front board plate.
6. Sv resistor assembly (J300)— Retainer screws (E208 x 2)
7. Hot shoe contact (3204) — Hot shoe contact screw (3209 x 2)
8. P.C.board retainer plate (J205) — P.C.board retainer screw (J208), Spring (J206)

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9. P.C.board assembly (J500) — CNM 1.7 x 2.5 x 2
Base plate screw (A41-01)
10. Unsolder lead wires. 8 pcs
11. Mirror housing complete assembly (B000)
a.) After loosening Screw (M75), disconnect Idle gear assembly (0-M74) and Supporter plate
assembly (0-M53).
b.) Remove Mirror housing complete assembly (B000) together with Prism seat assembly
(0-M1), Penta prism assembly (0-L3) and Cell frame (J201).
12. Terminal contact assembly (0-J611) — CNS 1.7 x 2.5
13. Battery seat assembly (0-A8) — CNS 1.7 x 2.5 x 2
14. Restitution spring assembly (0-M62)
a.) Idle gear assembly (0-M74), Idle gear supporter plate (M73)
Screw (M75)
b.) Remove Bobbin (M85) — CNL-B 1.4 x 2.0
Without turning brass gear.
c.) Adjusting plate assembly (0-M68), Pulley seat assembly (0-M76)
Left handed screw (M72)
d.) Restitution spring.assembly (0-M62), Hinge retainer spring (A5)
— CNM 1.7 x 2.5 x 2, W3
15. Governor actuator plate (C252) — Screw (C253), CNL-E 1.7 x 2.5
After removing (C252), install CNL-E 1.7 x 2.5 again.
16. Slow governor assembly (C100) at 1/125 shutter speed.
— CNM 1.4 x 2.0, CNM 1.7 x 2.0
17. Governor restitution plate (E407), (E408), (E409), W3
18. Slow speed cam assembly (0-E402), Nut (E406) — 23800K-E406-A
Caution:
a.) Remove Nut (E406) grabbing slow speed cam shaft (E401) with plier, without turning
(E401).
b.) Remove (0-E402) by loosening two set screw, at 1 sec shutter speed.

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19. Pinion coupler gear assembly (0-C249) — CNL-E 1.7 x 2.5
20. Pinion coupler lever assembly (0-C254), (C257) (C 137)
21. Coupler lever spring (C266).Coupler lever spring hook screw (C214), Cord holder (J525).
22. Coupler lever assembly (0-C244), Coupler lever retainer screw (C248) — left handed.
23. Installing seat assembly (0-A508) — CSS 1.7 x 2.2 x 2
24. SW plate assembly (0-J521) — CNL-D 1.7 x 3.5
25. Bulb coupler lever spring (C263)
26. Install Winding lever assembly (C300) with Retainer screw (C305) temporarily, and cock the shutter.
27. Shutter seat plate assembly (E200) — CSS 1.7 x 3.0 x 3
High speed cam assembly (E210)
Selector gear collar (E123)
28. Slow speed cam shaft (E401)
LW 17, W70
29. Winding seat assembly (C100) — Nut B (E144).CNM 1.7 x 3.0, CSS 1.7 x 2.5
30. Release plate assembly (0-A502) — CNL-D 1.4 x 2.0
Shutter actuator plate A assembly (0-A504)
31. Shutter rod spring (A514)
Shutter rod assembly (0-A501)
32. Self-timer (H100) — CNM 2.0 x 9.0, CNM 1.7 x 3.0
33. X contact seat assembly (0-J621) — CNS 1.7 x 2.5 x 2
34. High speed lever assembly (0-E126)
a.) Indication spring (E134)
b.) Nut A (E133)
c.) (0-E126) Indication plate assembly (0-E132)
35. Bottom winding mechanism
a.) Bottom main gear screw (C265) — left handed
b.) Winding transmission plate (C221)
c.) Bottom main gear retainer plate (C220)
d.) Bottom main gear (C219)
e.) Bottom main gear retainer (C269)
f.) Winding shaft supporter plate (C270) — W24
g.) Winding shaft receptacle (C218)
h.) Spool gear assembly (0-C216) — W16 (0.3t)

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36. Winding shaft assembly (0-C19)
37. Restitution retainer lever (C22)
a.) Supporter screw (C24)
b.) (C22)
c.) Restitution lever spring (C25)
d.) Collar (C23)
38. Coupler pinion (E11) — Retainer screw (E12)
39. Reversing plate (E111)
a.) C137 — b.) E111 — c.) E112 — W6
40. Intermediate gears
a.) E107 — b.) E106 — c.) E104 — d.) E105 — e.) 0 E101
41. Hook plate (E153)
a.) E154 — b.) E155 — c.) E153 — W1
42. Top 2nd gear assembly (0-C9)
Top 2nd gear shaft retainer nut (C11)
231K-E111-A or 234K-B83-A
• 43.Bounce stopper (E145)
a.) E147 — b.) E146 — c.) E145 — W3 — d.) E152
44. Shutter curtain light seal (A17)
After releasing the shutter, remove (A17)
— CNS 1.7 x 2.5 x 2
45. Curtain stopper (E139)
a.) After releasing curtain tension, remove Worm (E41 x 2)
b.) Worm wheel (E42 x2) — left handed.
c.) Curtain stopper screw (E143) — 23800K-E143-A
d.) Curtain stopper retainer screw (E142)
e.) (E140), (E141)
f.) Not removing Curtain stopper (E139), retain it with (E142)
46. Shutter curtains
a.) (C27) & (C28)
b.) Curtain plate assembly (0-A25)
c.) Shutter curtain mechanism
0-C1, 0-E36, 0-E38, etc.
47. Top shaft receptacle (C17)
Stopper retainer screw (C18) — CNS 1.7 x 1.8 x 2
48. Idle gear (C624) — CNL-F 1.7 x 1.8
49. Bottom shaft receptacle (C202)
W73, CNS 1.7 x 1.6 x 2, CNS 1.7 x 2.5

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50. Coupler gear assembly (0-C222)
Coupler gear retainer screw (C226) — left handed
51. Rewinding actuator lever assembly (0-C241)
a.) CNL-B 1.4 x 2.0
b.) Spring retainer.(C243)
c.) Rewinding actuator lever spring (C242)
d.) 0-C241
52. Bottom mec.plate assembly (C200)
a.) Stopper pole (C267) — CNS 1.7 x 2.5
b.) Coupler guide (C268)
c.) C200
d.) Sprocket (C236)

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Assembly procedure
1. Bottom mec.plate assembly (C200)
a.) Sprocket (C236)
b.) Bottom mec.plate assembly (C200) — positioning with (C202)
c.) C268, C267, CNS 1.7 x 2.5
2. Spool a.) Install spool (0-C20) and Spacer (C29)
b.) Top shaft receptacle (C17-01)
c.) Bottom shaft receptacle (C202)
Vertical clearance of Spool is adjusted with W73
(t=0.5 or 0.6mm)
d.) Idle gear (C264)
3. Rewinding actuator lever assembly (0-C241)
As shown in Parts list
4. Coupler gear assembly (0-C222) — (C226) = left handed
a.) Sprocket teeth is positioned as shown in Figure
b.) When installing Coupler gear assembly (0-C222), it should be positioned as shown below,
besides sprocket teeth should not be moved.
5. Shutter curtains
a.) Top mec.plate assembly (0-C1) — C27, C28
Curtain strings should not be off from rollers.
b.).Curtain plate assembly (0-A25)
Arrangement of both curtains is opposite from SP type camera.
6. Worm (E42) and Worm wheel (E41)
Turn worm wheel two rounds to give the tension to both curtains.
7. Check 2nd curtain position after releasing 1st curtain
a.) Install High speed lever assembly (0-E126) temporarily.
Cock the shutter, and release 1st curtain, 2nd curtain should be staying at 5mm distant
from picture frame.
Shutter cocking tool — 23800K-E113, E124-A.

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b.) When both curtains are wound and hooked with 1st curtain ratchet assembly (0-E135), adjust the
clearance at 0.1mm between high speed.lever and Bottom selector gear assembly (0-E124) with
turning Adjusting stud (E122).
8. Curtains overlapping
After cocking the shutter, both curtains should be overlapping completely or within ± 0.1mm
deviation.
9. Bounce stopper (E152)
E152 — W3 — E145 — E146
10. Curtain stopper (E139)
E139 — E140 — E142 — E143 — 23800K — E143-A — E147
11. Top 2nd gear assembly (0-C9)-C11
12. Coupler pinion (E11) — E12 before cocking the shutter.
13. Restitution retainer lever (C22)
C23 — C25 — C22 — C24
14. Winding shaft assembly (0-C19-01)
a.) Clearance between (C22) and (0-C19-01) should be 0.4mm

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b.) Bottom winding mechanism
W16 — 0-C216 — C218 — W24 — C270 — C269 — C219 — C220 — C221 — C265
(left-handed)
Caution;
* W16 should be installed first separately from (C216), otherwise (C216) can not be installed
together with W16.
* When (C219) is installed, sprocket teeth should be positioned correctly as mentioned before.
Perforation is adjusted definitely here.
15. Reversing plate (E111) and hook plate
a.) E112 — C26 — W6 — E111 — C137
Check the function and play of (E111), the play should be
within 0.1mm
b.) W1-E153 — E155 — E154
16. Intermediate gears — Shutter cocked
a.) Sprocket teeth should be positioned correctly as mentioned before.
b.) b.) 0-E101
c.) Spill (E105)
d.) E104
Clearance between (E104) and (E105) should be desirably closer to (0), but (E105) must move up and
down smoothly without catching (E104).

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17. High speed lever assembly (0-E126)
— 0-E126 — 0-E132 — E133 — E134
* After installing the above parts, 1st curtain ratchet assembly (0-E135) functions
automatically.
18. X contact seat assembly (0-J621) — CNS 1.7 x 2.5
19. Self-timer (H100) — CNM 2.0 x 9.0, CNM 1.7 x 3.0
* Install self-timer pushing upper left.
20. Shutter actuator plate A assembly (0-A501)
0-A501 — A514 — 0-A502 — 0-A504 — CNL-D 1.4 x 2.0 x 3
21. Winding seat assembly (C100) — together with winding lever
— Back cover open.
* Confirm the position of transporting claw before installing as shown in figure.
* Straight parts of transporting claw should align with the center of Nut B (E144) with shutter
cocked and back cover close.
* Check counter dial movement, counter dial should be transported till 37 point, not 38. If
counter dial proceeds till 38 point, reinstall Winding seat assembly (C100) as mentioned
above.
* After cocking shutter, check the clearance between Curtain stopper (E139) and Top selector
gear assembly (0-E113), 0.1mm is enough.

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22. Slow speed cam shaft (E401)
E401 — E405 — LW17 x 3 — W70
* Up and down play of (E401) should be within 0.1mm.
23. Shutter seat plate assembly (E200)
a) Cock the shutter
b) Put on selector gear collar (E123)
c) High speed cam assembly (0-E210)
d) Install (E200) taking care of jointing part with slow speed cam shaft.
24. Bulb coupler lever spring (C263)
25. Switch plate assembly (0-J521) Main SW
— CNL-D 1.7 x 3.5 x 2
* When installing it, take care of shortage or leakage to camera body.
26. Installing seat assembly (0-A508) — CSS 1.7 x 2.2 x 2
27. Coupler lever assembly (0-C244)
a) Cord holder (J525) — Coupler lever spring hook screw (C214)
b) (0-C244) — Coupler lever retainer screw (C248) — left handed
c) Coupler lever spring (C266)
d) Check the function of (0-C244)
28. Pinion coupler lever assembly (0-C254)
W70 — 0-C254 — C257 — C137
29. Pinion coupler gear assembly (0-C249)
* After installing (0-C249), (0-C254) should not touch to (0-C249).
See Figure (a)
* After winding up, the least clearance (0.1 — 0.2) is necessary between the rivet of
(0-C249) and the lever of (0-C254). See Figure (b)

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30. Slow speed cam assembly (0-E402)
a) Shutter speed at B
b) Small rivet of (0-E402) should align straight with the center of (E401) and sprocket shaft
as shown in Figure, and fasten Nut (E406) catching (E401) with pliers.
Fasten set screws also.
* When (E406) is fastened without catching (E401) with pliers, jointing split part underneath (E200)
spreads with revolving power of (E401), and slower shutter speed will be affected.
31.Governor (G100) — CNM 1.7 x 2.0, CNM 1.4 x 2.0
a) Shutter speed at 1/125
b) Install (G100) without bending small levers (such as angle lever etc).
32. Governor actuator plate (C252)
a) Shutter speed at B
b) Cock the shutter
c) (C252) — (C253) x 2 as shown in Figure
33. Shutter curtain light seal (A17)— CNS 1.7 x 2.5 x 2

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34. Tv indication
a) Shutter speed at 1/1000
b) Lower pulley of Pulley seat assembly (0-M76) should be in parallel with camera.
c) Adjusting plate assembly (0-M68) — (M72) = left handed
d) Restitution spring assembly (0-M62) — (A5) — (M85)
* Turn wire 1 turn counter-clockwise around the pulley of (0-M62)
* After installing (0-M62), Tv wire should not be loose.
•If it is loose, give tension by moving (0-M68), but too much tension makes it harder to
adjust the position of Indication plate (M61).
e) (M73) — (0-M74) — (M75)
* Gear of (0-M62) and (0-M74) should be gearing not too deep, and check the function.
35. Mirror housing complete assembly (B000)
a) Battery seat assembly (0-A) — CNS 1.7 x 2.5 x 2
b) (B000) should be installed taking care of coupling two gears (M74) and (0-M53).
c) (E407) — (E408) — (E409) — W3

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36. Terminal contact assembly (0-J611)
Soldering lead wires 8 pcs.
37. Shutter speed adjustment
a) Curtain speed 12.2 — 12.3ms
Same way with SP camera.
b) High speed adjustment 1/1000 — 1/60ms
Same way with SP camera
c) Slow speed adjustment 1/30 — l sec
1 Loosen screw
2 Adjust with eccentric screw
3 Fasten screw
4 Apply red lacquer on screw
38. Shutter stroke — Shutter dial at B
a) Install Top cover assembly (A300) and Winding lever assembly (C300) temporarily.
b) Depressing shutter button gradually, shutter starts working at 2.1 ± 0.2mm from origina1
position.
c) Self-timer exposure time adjustment at B.(Around 1000ms)
39. Main SW keep adjustment Main SW stroke
— 0.6 ±0.2mm
40. Tv indication
a) Shutter speed at 1/1000
b) Positioning adjustment of Supporter plate assembly (0-M53).

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1 Tv indication dial should be set just
center portion of viewing finder.
2 Tv indication (1000) should be set as
shown in Figure.
3 Three jointing gears (0-M53), (0-M62)
and (0-M74) must function well.If they
do not, adjust the position of Idle gear
supporter plate (M73) with eccentric
screw A
4 Each figure of Tv indication must come
in the center portion, adjusting eccentric
screw B
41. Front board plate assembly (A100).
Mechanical back 45.46mm
42. Sv resistor assembly (J300) — (E208)
43. P.C.board assembly (H500)
a.) LED
(A41-01) — W3 — CNM 1.7 x 2.5 — CNL-D 1.4 x 2.5
b.) GPD
(J205) — (J206) — (J208)
c.) Bonding (J500) to Penta prism cover
d.) (J204) — (J209) x 2
44. Soldering lead wires — 7pcs
45. Bottom cover assembly (A400) — CSS 1.7 x 2.2 x 3
Tripod screw (All) — CSM 1.7 x 3.5 x 2
46. Adjustment of LED indication place

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47. Light measurement
a.) Temporary setting — Top cover tool, shutter dial, winding lever
b.) Battery checker — VR A
EV12, f8, 1/60, ASA100
2.6V Light off
2.7V Light on
c.) Light measurement — VR Bor VR C
EV12, f8, 1/60, ASA 100, 2.8V
When shutter dial is turned 1EV step (1/60 — 1/30 and A/60 — 125), and both red LED
(over and under) light on, it shows within 0.1EV difference.
d.) Confirmation of voltage reliability
EV12, f8, 1/60, ASA100
When voltage is dropped down from 2.8V to 2.7V, LED indication should not change.
e.) When mirror stays up, LED should not light on.Check it at B.
48. Focusing adjustment
a.) Removing Top cover tool and others
b.) Adjust focusing with Focusing screw (M6) x 4
49. Adjustment of Focusing plate holder assembly (0-B101)
If vertical play is felt on (0-B101), remove Cover plate (B109) and adjust the position of
Hook metal assembly (0-M107) with eccentric screw.
50. Top cover assemb1y (A300)
Winding lever, shutter dial, rewind knob and other small parts.
Tools — 23110K-D16-1-A
23800K-E231-A
23600K-C135-A
51. Bonding Coverings (A19 & A20)

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ASAHI PENTAX MX (23800)
Curtain assembly
1. Curtain inspection
Check if Aron-alpha is applied to curtain string as shown in
Figure.
Aron-alpha is applied to increase durability.Curtain string
should be, bent parallel with shutter curtain.
2. Install 1st and 2nd pinion shafts (0-E2, 0-E7), (0-E118), (0-E108), (0-E135) and 2nd curtain assembly
(0-E38) to Top mec.plate assembly (0-C1).
3. Install Top mec.plate assembly (0-C1) to camera body temporarily.
4. Give slight tension to 2nd curtain.
5. Install 1st curtain assembly (0-E36) and Curtain plate assembly (0-A25).
Give slight tension to 1st curtain.
Arrangement of both curtains is opposite from SP type
camera.
Install 1st curtain (0-E36) engaging 2nd curtain string
with the rollers.
6. Removing Top mec.plate assembly (0-C1) from camera body for a while, engage 1st curtain string with
the 2nd curtain pinion rollers and re-install Top mec.plate assembly (0-C1) to camera body without
slipping off the string from rollers.
7. 2nd curtain hold position — with shutter cocked 2nd curtain should stay at 5mm distant from picture
frame when High speed lever hooks Bottom selector gear assembly (0-E124).
Adjust the position of 2nd curtain with changing the coupling between 2nd pinion gear and (0-E124).
8. Install Top selector gear assembly (0-E113) with shutter released, facing the retainer screws of 1st
curtain pinion 45°forward.

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9. Install adjusting plate (E120) and other parts.
Adjusting plate (E120) is installed after
turning Top selector gear and Selector
retainer (0-E118) to cocked position.
10. Install 1st curtain string to bobbin (E3).
Confirm curtain overlapping and slit parallel, with adjusting the
length of 1st curtain string.Aron-alpha is applied to curtain string
and its retainer screw (CNS 1.4 x 1.6) after adjustment is finished,
and cut the curtain string after turning around the Bobbin one time
on the other way.
11. Clearance between Bottom selector gear assembly (0-E124) and High speed lever assembly (0-E126)
should be adjusted at 0.1mm with cocked position by turning Adjusting plate (E120).
After adjustment, apply aron-alpha to Retainer screw (E121).