Project:

A video transmitting remote controlled blimp.

Designer(s):

N8UDK / N8QPJ

Description:

Once a year the L'anse Creuse Amateur Radio Club does a great job promoting amateur radio by sponsoring a demonstration of the many facets of amateur radio at the Macomb Mall in Roseville Michigan. So not to leave ATV out, Mark N8REZ, Dave N8HUL, and Doug N8PYN do a great job of showing some really cool ATV applications. This year Jeff (N8QPJ) and I put together an RC (radio controlled) blimp as an extra attraction. For six hours on that Saturday we enjoyed flying a seven foot helium filled blimp which included a very small ATV transmitter and a gondola mounted camera.

Some Technical Information:

The payload consists of a 100 mw transmitter (434.00 MHz out) which uses a tuned wire for the antenna. The camera is a 225 line black and white model from ATV research. The transmitter and camera were selected for this project because of their weight (1 oz. total) and minimum power consumption (only 45 ma total). For reception I used the M2 eggbeater antenna with optional ground plane. I attached the antenna with a short mast to a patio umbrella stand. The antenna feeds my TV/VCR unit which is tuned to cable channel 59 . The blimp itself has two motor mounted push propellers which mount onto the ends of a dowel that intersects the gondola. The dowel rotates 180 degrees rotating both motors up 90 degrees and down 90 degrees. The motors have a speed control and useful reverse capability. So to gain altitude I pull back on the control box elevator stick which causes the propellers to rotate down and then I give the propellers some forward speed. To make the blimp lose altitude I push forward on the elevator stick causing the propellers to point up and once again apply some thrust. Turning is done by a technique called "differential thrust". Using the aileron stick on my control box I can cause one propeller to rotate clockwise and the other propeller to rotate counterclockwise. The balloon part of the blimp takes about 20 cubic feet of helium. Caution is required not to over inflate the balloon. As the gas warms it expands. I purchased an eighty cubic foot tank of gas so I can get four flights before having to get a refill. Once the blimp is filled it will remain buoyant for several days.

Hardware:

• Indoor seven foot blimp with gondola
• Fubuta FP-5UAP PCM RC transmitter and receiver
• 225 lines black and white camera
• 100 mw ATV transmitter
• Eggbeater 440 receiver antenna
• 8mm VCR and TV

Hardware Sources:

• Mobile Airships, Inc. (519) 756-1110
• ATV Research Inc. (800) 392-3922
• Tower Hobbies (800) 637-6050
• M2 (209) 432-8873

Conclusion:

The blimp flew flawlessly and the six hours of video was great. I believe we had success in drawing more passers-by to the L'anse Creuse displays. At least some were curious about what it looked like from the blimps point-of-view on TV. I was amazed how many people never looked up! Many interesting reactions once they did though. Regardless, it was a lot of fun. Hey, how often do you get a chance to fly a video transmitting seven foot blimp in the mall?

- Chris Oesterling N8UDK

Fig 1.0 - "The ATV blimp gondola"

Fig 2.0 - "The ATV blimp in the mall"

Fig 3.0 - "Received transmission from the ATV blimp"