About:
There have been several times where I wish I could make my camera take pictures via remote control for things like group photos, nature shots, or self pictures. The time delay works fine, but really if there are pets in the shot or you want to take several to choose the best, then a wireless control is really they only way to go. So one day I had an idea, why not combine a tethered-gps-shutter-button with a wireless toy car? Brilliant! Granted this product already exists, but anything less than $50 is junk, dont believe me? Read the ratings on Amazon. Mine works at 35ft, can remain on for 14days continuously (provided the camera doesnt die first), and cost me less than $15! The GPS Shutter was $3 on Amazon, and the Coke Can Remote Controlled Car was from eBay for $5. The rest was spent on parts here and there.
Failed First Attempt:
This technically worked, but I wasn't happy with how it worked. First off the range was pretty bad, like 5ft bad. At that distance you might as well have a cord. Turned out the way I moved the antenna in the car-remote was responsible for this. Instead of having it stick out the top while the remote is laying down, I tried to mount it such that it stuck out the top when standing up, like a phone. Since this killed the range, I had to go back to the ugly way.
For the tethered camera shutter button thing, I had to give it an external port. To do this I soldered a 1/8 mono mini jack to the ground and shutter contacts, bypassing the focus thinking if you go straight to shutter it will focus anyways. Not in the D3100. So the tethered shutter has a liitle lock over the button so the button can be held down, but doing this pressed all 3 contacts together, gnd, focus, shutter, so inside I shaved away some plastic so the lock would only touch the gnd to focus. NOW my device would work. If you lock the tethered shutter into focus, then my remote would take the picture by shorting to shutter, BUT to use my remote means the camera has to be stuck in focus mode, which would run down the camera battery, so after a few hours I abandoned this implimentation. I removed the mono mini jack, connected a stereo jack, and soldered the third wire, focus. Now my remote can short all 3 contacts (gnd, focus, shutter) when sending the desired command, allowing the camera to remain idle when not in use; saving precious battery life.
Coke Can Car:
The most fun part of this project was figuring out what all the contacts did on the toy car circuit board. Once documented, I could desolder everything and save only what I needed. Not wanting to waste anything, however, I put the toy car back togehter such that it would still drive, just with out control, only on or off, something for the kitties to chase.
Final Revision:
With the main circuit modified, the tethered shutter fixed, and the remote-antenna moved back to the way it was, the thing works fantastic! By placing a longer antenna on the reciever circuit attenuated to exactly 1 wavelength I can now squeeze 35ft out of this thing! And the best part, despite a few hours of my time, it was fun and only a fraction of the cost of a comparible unit.
