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Transmitter Test Failure!
Updated: May 25, 2007

We had a very encouraging series of hideous failures during the transmitter bench testing on May 25. The photos and captions below will walk you through it from start to finish.

Test Bench Setup
In this picture you can see that we have remounted the microwave innards on a vertical transmitter assembly. Ideally, I would have liked to have kept the entire unit intact, and simply mounted the entire oven on the main boom 20 ft. in the air. This is not practical, as it would mean that someone would have to sit up there and push the "start" button when we wanted to transmit, and practicality became an overwhelming consideration. As it stands, the vertical transmitter assembly will be covered and mounted on the boom, and wires will run down the structure to the original oven controls on the ground.
Another Test Bench Angle
You can see that the fire extinguisher has been removed from its less than optimal position 15 inches from the transmitter. Generally, you don't want to put the fire extinguisher in the location that is likely to be engulfed in flames. For the testing we moved it to the far corner of the shop by the power cutoff where we crouched during the experiments.
Top View
A view from the top of the assembly showing particular detail of the startup capacitor. If you ever see one of these laying on the ground or on the seat of your car, do not, I repeat do not touch the two terminals on the end at the same time. Capacitors store a huge amount of burst energy (kind of like a battery that blasts out all its energy in 2 seconds) and can really do a lot of damage fast. Just back away and call the authorities if you ever see one laying around.
Top View 2
Top view showing the thermometer in the test medium. We removed it for the actual test, as it would have gotten fried.
Reverse Angle
There was some concern that the preponderance of wood in the assembly and test area might be a fire hazard. The concerns were dismissed as namby pamby, and the tests continued!
Top View 3
With unchecked electromagnetic radiation flying everywhere, it was deemed too risky to take any closeup pictures of the assembly while the transmitter was actually on.
View from the Test Bunker
This photo is taken from the "observation area" which we located at the far end of the shop behind a very sturdy looking '63 Chevy truck. From this location we could see the transmission unit in operation and our eyeballs were protected by several layers of shatterproof glass (our vitals, of course, were shielded by at least 4 inches of good ol' Detroit sheet metal from back in the day). From this location we were confident that we could see anything major developing (fire, flash-boiling water, melting metal, etc.) and cut the power while keeping our exposure to flying debris to a minimum. The photo isn't so good, partly due to the flash reflecting off the glass, but mostly because an OBBR technician has just lunged out of the frame to disconnect the power in response to an extremely menacing hum emanating from the transmitter (this test was aborted after 4 seconds).
Failure!
After 60 seconds of point blank microwave blasting, the test medium shows zero change in temperature - indicating, what we believe to be - total failure. The weird hum might have had something to do with it, the splicing in of copper leads instead of the factory issue Ni Chrome wire connecting the transformer to the magnetron or just general negligence/incompetence might have caused it. It isn't really that complicated a machine, and we didn't really modify it that much in constructing the vertical housing, but it appears to have defeated us for the moment. Whenever I have a project catch fire, short out the power for a city block or simply fail to work at all, I am always encouraged however. I just think of NASA's Redstone rockets blowing up on ignition, spinning out of control or moving 6 inches upwards before gracelessly falling to the side and exploding. Just a few short years after those numerous and spectacular failures, they had guys flying all around space talking with Texas accents. I view failure, therefore, as the sure sign of imminent success.


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