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Liquidslow
Tinkerer
Username: Liquidslow
Post Number: 1
Registered: 06-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 11, 2008 - 01:33 am: | 
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Hello. I'm totally new to the forum, I hope no one gets offended if I ask some dumb question.
So here's probably some  .
I've just got a Canon A-1 body. I have no FD lens, since I bought it separate and it didn't arrive yet. I'm new to Canon FD.
I made some tests with no lens mounted. I don't know whether the camera will operate correctly with no lens.
The viewfinder info LEDs are suppose to light even with no lens mounted? Because it's not.
Shutter is working so-so. Shutter is cocked but sometimes it doesn't release. When it does, sometimes the mirror doesn't return. Magnets? I opened the bottom plate and the magnet to the right-hand is not releasing. I have to reset the camera to L or press the battery test button to return the mirror up.
Shutter speeds are odd, I think the AT dial is not setting any speed, apparently, not even bulb mode. It's the same for Tv or Av. The battery I'm using is not new, could it be that? Or is it all because of the no-lens situation?
The self-timer doesn't seem to be working, and strangely sometimes when I press the shutter when it's at A position, the 10 sec self-timer starts all by himself, apparently at random.
I'm really lost here, would anyone shine some light, please?
I'd really like to put the A-1 to work by repairing myself.
Thanks in advance! |
Scanogram
Tinkerer
Username: Scanogram
Post Number: 7
Registered: 04-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 11, 2008 - 07:20 am: |
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It's been years since I've worked on an A1 but I saw quite a few when I worked in camera repair full time.
Sounds like you have a lot of intermittant problems. First off, check the battery and look for corrosion in the battery box. Remove the bottom cover and look for corrosion around the motor drive contacts. Thats all the easy things I can think of.
The viewfinder LEDs should light even without a lens. The LED flex circuit could have a bad connection to the main flex circuit board. The circuits are press fit together and held with screws. When the LEDs failed I would replace the circuit board.
I would often find cracks in the flex circuit where it wrapped over the prism. If you see brown wire, you know someone has jumpered a crack in the circuit. Canon did not use brown wire in the A series cameras and that color was designated for repairs.
I have a few notes on the A1 and they say for top removal, Remove top with speed dial in "A" position. They also say to look for a bearing under the cover, not sure what this means, I wrote these notes over 20 years ago.
Be very careful and take good notes. Even then if you've never done this you could damage your camera or not be able to reassemble it.
My best guess is battery corrosion or the connections between the circuit boards. Battery corrosion can follow the wire from the battery box up to the circuit board and damage it. You have to remove the mirror cage to get to the battery box and wire. You probably don't want to attempt that. |
Peterclarke
Tinkerer
Username: Peterclarke
Post Number: 25
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 11, 2008 - 10:51 am: |
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Are the viewfinder LEDs switched on? The lever on the switch on the top plate between the prism housing and the rewind/film speed knob should be in the position nearest the prism housing so that the white dot is visible. If the lever is covering the white dot the LEDs are switched off. The button in the middle of the switch is for testing the battery. If there is enough power the red light next to the shutter release will flash when the button is pressed. Of course the camera must be switched on. I hope this information is helpful. Peter |
Liquidslow
Tinkerer
Username: Liquidslow
Post Number: 2
Registered: 06-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 11, 2008 - 06:38 pm: |
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@Scanogram:
Thank you for the tips. You are right, it's probably an electronic problem. I tested with fresh batteries and it's the same. I checked inside the top, bottom and the battery chamber and nothing is corroded, cracked or strangely bent. No brown wire either (nice tip). Bad sign, I guess...
@Peterclarke:
Ok, I checked that on both position. No go. And contacts are not bent inside the camera top. Another thing I noticed is the battery test button actually interferes with the camera shutter operation. Pressing the test button is possible to cancel the self-timer and to free up the jammed mirror. |
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