Pentax EPK-i - Service; Lamp Block Replacement

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Photo-2 Lamp block
Screw x3
Hook
Heat sink
Rear Front
6. Service
Note: Refer to Photo-1 for the location of the parts to be replaced. And also refer to appendix pages for wire routing.
6.1 Lamp block
A way of replacing the lamp bulb and reusing the heat sink is described below.
Important: 1) This job must be done by a person who has got the service training for the EPK-i.
2) The IR cut filter cannot be reused, must be replaced together with the lamp bulb. A spoiled
filter may cause heat injury due to intensive light through the scope.
1) Take out the lamp block from the lamp house.
2) To detach the old lamp, unscrew the three screws and release the hook.
See Photo-2. Remove Front heat sink by rocking it.
Hint: It may be hard to detach Front heat sink and occasionally Filter ring
comes off attaching on the lamp bulb. In this case, put Filter ring back
to Front heat sink.
3) Replace the IR cut filter with a new one in the following order:
a) To remove Spring ring from the ditch in Filter ring, insert the tip of
the thin screw driver into the hole of Filter ring and push the end of
Spring ring toward the center a little bit and lift it by the tip of the screw
driver. See Photo-3 left.
Hint: If the end of Spring ring is not located at the hole of Filter ring, rotate
Spring ring by pressing the other end with a screw driver to be so.
Caution: 1) Do not apply excessive force to Spring ring when detaching it so as not to spoil it.
2) Spring ring may pop out when detaching it. Cover it by a palm.
b) Replace IR cut filter with new one without tainting nor scratching it.
Hint: Confirm if IR cut filter has settled horizontally in Filter ring.
c) Pinch both ends of Spring ring (shown by coloring in red) with two pairs of tweezes and then put
Spring ring into the ditch of Filter ring while narrowing the cut in Spring ring. See Photo-3 Right hand
side.
Hint: The opposite part (shown by coloring in green) against the cut in Spring ring should be put into the ditch of
Filter ring first and the rest of the ring will be put into the ditch subsequently.
Caution: Do not taint nor scratch IR cut filter while attaching Spring ring. If it is tainted, clean it carefully with
isopropyl alcohol solution. If it is scratched, discard it.
d) Confirm if IR cut filter and Spring ring have been attached correctly by waving Front heat sink. If a
click sound can be heard from IR cut filter, it is OK. If not, do it from scratch.
Screw driver
Filter
End of Spring ring
Hole of Filter ring
Front heat sink
Filter ring
Spring ring
IR cut filter
Spring ring
Tweezes
Tweezes
Narrow the cut
Photo-3 IR cut filter replacement