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Part I: Basic Hacks, Tools, and Techniques
Reinstall the camera on top of the pole and reattach all of the wiring. You
now have a video periscope that will allow you a unique view of traffic!
Test out the camera assembly
Take the entire assembly out to the car, but do not attach the trunk
mount—you first want to see if everything works. Plug in the video camera
to the LCD TV set and plug the power cable into the power supply. Connect
the power supply to the 12V cigarette lighter and see if there is a video pic-
ture on the LCD TV.
Close the trunk of the car over the cables and connect the camera. Plug in
the cigarette adapter and look for video. Don’t go for a ride just yet—you
will need to check the weatherproofing at the enclosure and tighten all of
the tie wraps.
Adjust the Madol antenna mount to give you the view you want. It can be
oriented forward to get a peek at traffic up ahead, or backward to see what
(or who) is behind you.
Extensions
Once you have the camera working, you may want to experiment with dif-
ferent configurations. Here are four examples.
Multiple cameras
Multiple cameras can be attached
around the car. Simply purchase and
build additional cameras and hous-
ings and add a multi-pole switch to
rotate the power and video among
the different cameras. Figure 6-21
shows an example of how multiple
cameras can be connected.
Motorized mount
If you want to be able to rotate the camera left and right, you can use a
model airplane servo. Pick up a medium-size servo and mount it to the pole
and the camera. You will need some sort of control circuit to send position
information to the servo; a simple circuit that accomplishes this is shown
in Exhibit C. The circuit consists of an LM55 timer IC, a few resistors and
capacitors, a transistor, and a potentiometer. Build the circuit and mount
it in a small box with a large potentiometer sticking out. Add a knob that
allows rotation of the camera to be controlled from the front seat of the car.
Color LCD TV
Digikey
401-1027-ND
Digikey
CKC7007-ND
Camera #1
Camera #2
Camera #3
Video input
12V from car
Figure 6-21: Multi-camera setup
Extensions
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Chapter 6, How to Hack a Video Periscope for Your Car
If you feel ambitious, you can build a microprocessor-based servo control-
ler and have the camera pan automatically. I will leave this as an exercise
to you.
When mounting the servo, you will need to build a small cover to prevent
water from getting inside the case. (This cover is not needed if you only
want to use the camera inside the car.)
Battery-powered version
If you want to use the camera as a portable periscope, you could use six D
batteries to power up the set. Put them in a small case, and you can now
look over fences and walls without being detected.
Connect a video recorder
You have probably seen the television programs “COPS,“Dangerous Car
Chases, or similar real-life highway patrol programs. Much of the video
from these shows is from in-car video cameras and recorders. Using the
video periscope and an old VCR, you can set up a similar system for your-
self.
Locate an old but functional VCR, a 12V to 120V voltage converter (available
at Radio Shack and many auto-supply stores), and a basic microcontroller.
Connect them as shown in Figure 6-22. You will need to connect the con-
troller to the remote control so that the Record button is pressed 10 to 20
seconds after the system is powered up. I will leave the details of this project
up to you.
Figure 6-22: Camera recording system
LCD TV
Camera
Power
Video
VCR
Video in
Video out
Video
Power
Camera and LCD TV
power supply
12VDC to 120VAC
converter
120VAC 12VDC from
cigarette lighter
Basic microcontroller
VCR remote control
Extensions
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