Turn a 'toy' radar gun into a more pratical, useful radar gun with better features! While this is a completely new and different design, my inspiration for this project came from an article I read by Ken Delahoussaye. Check out the video and see it in action!

Step 1: The Brains...

This is the Hot Wheels Radar Gun. They are available at toy store and the internet. Cost: Approx $25. This is a real radar gun that shoots doppler radar at 10.525GHz. It has a trigger you hold down and will adjust to 1:1 or 1:64 scale for shooting Hot Wheels cars in action. It also will display MPH or KPH. Time to hack it!

Step 2: Parts You Need...

1. Drill with various bit sizes.
2. Cheap plastic bottle at least 8" long X 3 1/2" in diameter. ($1.50)
3. Assorted screwdrivers
4. Dremel and hack saw
5. Soldering gun with solder
6. Assorted wire
7. DPDT Toggle switch Radio Shack #275-0663 ($4.99)
8. 4-AA Battery holder ($1.59)
9. 1/4 X 20 Coupler nut and bolt with washers. ($.85)
10. Altoids tin
11. JB Weld

Step 3: Dissasemble the Radar Gun.

Using a drill, drill out the plastic filler caps that cover the screws holding the Radar Gun together. There are a dozen or so screws. After you open it up, remove the waveguide, LCD display, switch and battery compartment connector.

Step 4: Build It.

Cut off one end of the drink bottle and drill 4 holes. 1 dead center on the other side. One off center. 1 on topat the back end and one at the bottom on the back end (See the video for exact locations but these need to be measured up based on your bottle)

Step 5: Prep the Waveguide...

I JB Welded a bolt at the back of the waveguide to be used to fasten the waveguide to the drink bottle. Any size bolt will work as long as you have a matching nut.

Step 6: Wiring...

After making a note of where all the wiring is, unsolder all of the connections. You will end up with a waveguide, switch (not used), LCD diplay and battery compartment connector (not used). Solder new wire to the new toggle switch following the same pattern as the old one. Solder new wire to the waveguide.

Step 7: LCD Display Mount...

Cut a square in the Altoids tin bottom to match the size of the opening in the back of the LCD display and then mount the display on the tin using screws. I also used a little bit of hot glue to be sure. Drill two holes the top of the tin to match the holes drilled in the bottom of the drink bottle. Make sure things are lined up before you drill and hole!

Step 8: Assembly...

Install the tripod mount (coupler nut, bolt and washers). Install the toggle switch and route the wiring out the back. Install the waveguide, route the wiring through the hole in the Altoids tin, route the wiring from the waveguie through one hole in the tin and secure the waveguide with a nut over the other hole.

Step 9: Finish It Up!

Solder all of the wiring to the back of the LCD Display. Run two wires from the red and black power wires to the 4-AA battery holder. I hot glued and taped the connections so there would be no shorting going on inside the Altoids tin. I also secured the battery holder to the side of the new waveguide housing using heavy duty Velcro.

Step 10: Extra Touch...

for a little extra touch, I made a homemade hot shoe mount so it could be attached to a video camera. How come the poilce never thought of doing this? Maybe they have, but I have not seen it! Now, just a switch on to get your readings and increased life with the AA batteries instead ot he original AAA batteries. Have fun, Be safe!