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Jenna_alive
Tinkerer
Username: Jenna_alive
Post Number: 1
Registered: 10-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 15, 2009 - 03:49 pm: | 
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Even after replacing the battery on my K1000, the exposure needle hovers at center. It jiggles slightly, so I know it's not stuck.
My research has basically led me to understand that it could either be a) a broken wire inside the camera, or b) a dead galvanometer.
So if a wire is broken, is this something that I can replace myself? If so, what kind of wire do I need, and will it need to be soldered?
If it's the galvanometer, am I out of luck, or are these things still get-able somewhere?
Thanks in advance! |
Chiccolini
Tinkerer
Username: Chiccolini
Post Number: 56
Registered: 06-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 15, 2009 - 05:13 pm: |
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Wires don't break. They may disconnect from where they were attached. Wires, usually, don't come loose.
First thing you need to do is check the battery compartment to be sure it is clean from haze, gunk or whatever. Clean the contact points with either lighter fluid or rubbing alcohol on a Q-Tip. If you don't have that try any hard liquor 35 proof or higher.
The metering system on these is a cds sensor wired to the meter (the needle in the vf). There is no on/off switch. The lenscap serves as the "off". Ok, if you move the camera around and see the needle moving that only means the needle is still properly mounted on its pivot points but the galvano may still be dead.
Set the ASA dial as high as it can go, point the lens at some intense light source, set the speed dial to 15 and turn the aperture dial back and forth to see if the needle responds. Moving the speed dial will also have a similar test effect.
If you have a cheap volt meter you can test the galvano or CDS cell. Either of these parts should be available from a friendly repair shop or http://www.micro-tools.com/store/home.aspx |
Rick_oleson
Tinkerer
Username: Rick_oleson
Post Number: 994
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 15, 2009 - 08:11 pm: |
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Actually, broken wires in meters are very common. They corrode, I believe it's accelerated by galvanic action due to the constant (-) voltage bias held on the wire when the camera is stored with a battery in place. Look for a broken wire right at the battery box terminal. If it's broken, it will probably be rotten for an inch or two up the wire under the insulation, so you'll have to replace the whole wire, or a good chunk of it.
Another possibility in the K1000 is the photoswitch that shuts the meter off when you put the lens cap on (this is necessary because the center-biased meter in the Pentax draws as much current in the dark as in the light, unless something shuts it off - and of course they didn't put a conventional on/off switch on it). I haven't seen one of those go dead but it's possible.
rick |
Jenna_alive
Tinkerer
Username: Jenna_alive
Post Number: 2
Registered: 10-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, October 16, 2009 - 09:34 am: |
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Ok, I'm going to brave trying to open this baby up this weekend. I'm really hoping I don't screw it up, because the camera has a lot of sentimental value. I'll let you guys know what I find! |
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