This website is about a boat with a rotating radar made from tuna cans.
You can see my toy working in those videos:
Step 1: Attach the Motor
I found an old foam packaging material in my garage.
I purchased a low cost gear motor on eBay. This motor included a thin and long rod attached to motor gear output shaft. I used blue tack and thin insulated metal wire to attach the motor:
You can see in the second photo that underneath the motor there is a small weight. This weight is attach to the motor rotor and spins quickly with the rotor and used to drive additional loads. I had the make sure that the movement of this weight is not impeded by the foam structure.
Step 2: Attach the Radar
You can see the end of the motor shaft here:
I attached the two tuna cans with blue tack:
Step 3: Build the Receiver
My friend ordered this radio receiver from Oatley Electronics:
For more information click on this link:
Step 4: Connect the Wires
Design the Circuit:
Connect the circuit (I used soldering):
Step 5: Testing On Ground
I tested the motor spinning on the ground after assembling the boat:
Step 6: Testing In Water
I had to adjust the centre of mass because the radar was not spinning when the boat was slight tilted:
Probably the real source of problem was not tilted boat but the rusty motor gears. After a few minutes the radar would spin without any issues as you see in my videos:
Step 7: Distance Testing
The distance of the receiver could be at least 10 metres.
I had to drive the relay with two 9 V batteries making a total of 18 V. If I created 18 V by connecting D or even C batteries in parallel I would definitely burn the relays. The kit has a 9 V input but the relays were not turning ON even after I connected 3 V AA battery block in series with 9 V battery making a total voltage of 12 V that is needed for the relays.