SHAME! Shame on me… shame on me a million times. I haven’t been
posting like I meant to the past few months but I’m still here and still gladly accepting cameras for repairs. I’ve even found the time to post a few for sale
here and there. In fact, this is the most steady amount of cameras I’ve had in
quite some time – on average 3 cameras a week. I’ve also been building a new
portfolio for my artwork. Times are a changin' and I need to be prepared to
pick up and “go” at any time so I’ve been dedicating some more afterwork time
developing and maintaining my artsy fartsy skills. Add a day job on top of that
and weekend travel, that leaves about 8 hours a week for me to turnaround
cameras. I’m not complaining at all though. It keeps me out of trouble… :)
I had some time to go through my inventory and see what I
have as far as parts and donor cameras go and I realize that I’m getting low on
a lot of common needed components. The 3 most common parts that I use right up are lenses (half
of the submissions I receive are coated with fungus), motors (time takes a toll
on these suckers… most can be reconditioned), and sonar assemblies which I’ll
focus on in a bit. When I first started doing this repair gig as a hobby I’ll
admit I had no idea what I was doing or how to efficiently go about a repair.
If the autofocus wasn’t working, the natural thing to do would be to strip it
off of a donor camera and *blam*… good as new. Well now I have all these
components that have been stripped off of several other cameras and I can no
longer just swap assemblies because even trying to find a good donor anymore is
a hair pulling experience. So the next step would be to buckle down and learn
how to properly repair a specific problem with the AF. I’ve been doing this the
past few weeks… relying a ton on my multimeter and troubleshooting charts.
Most of the Sonar cameras I receive for repair have a common
problem - they all only focus only between 3 and 5 feet. I’ve had one that just
coasts… it can’t settle on a specific distnace, and I’ve had a few that jump their
focus directly to 10.4” (also known as ringing). Those two were relatively
simply fixes that require adjustments. However, the 3 – 5 feet only problem
requires sleeves rolled up, music cranked up loud, a non-shakey hand, 3 hours of
spare time, and a HUGE pile of patience. There’s a little component known as
the “pick-off” or it could also be called the encoder sensor. This part
essentially “counts” the number of holes on an encoder gear as it quickly
rotates. The transducer sends off a “chirp” that bounces off the subject back
to the camera and tells the gears to set in motion… the pickoff counts how many
revolutions the encoder gear has turned and based on the subject’s distance,
determines where the gears, in relation to the focal distance, should stop… now
focused on the subject. I’ve gone crosseyed thinking about how this works but
let’s just say the repair manual does a much better job describing the theory
of operation.
Long story short (too late), these pickoffs can go bad after
time and need to be replaced. I performed this procedure last night and I’m
very happy to say it was a complete success!! Pickoffs can be tested on their
own using a multimeter and I found that I have a ton of them in my parts bins. The
transplant required quite a bit of disassembly of the Sonar components in order
to unsolder the 4 wires that connect to the PCB board so having a good solder
workstation is a must for procedures like this. I couldn’t imagine trying this
with my 15 dollar Radio Shack iron. Reassembly was the biggest pain as the
gears need to be held in a particular spot in order to secure the lever arm
that adjusts the flash tilt as well as maintaining proper focal calibration. So there's a new repair that I can advertise!
*phew* I want to keep writing but I’m breaking my own
rule that there should be more pictures than words. So I’ll just add that I also
found a decent remedy for overexposed prints by removing corrosion from the
photodiode located on the back of the shutter PCB board. Removing the corrosion
allows more light to the photodiode which results in faster shutter speeds and
less light being allowed for exposure. So now I’m trying to make it a habit to
check the photodiodes for each repair. Although it’s more work and in some
cases, with older cameras, there’s risk of delaminating a board it’s worth it
in the long run knowing the camera goes back to the customer working properly.
Here's a shot of the pickoff replacement in progress... final assembly is shown in the diagram.
Before and after of the photodiode cleaning...
These cameras are currently for sale and are in need of a good home!
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