Measuring the voltage, current, and light output of a strobe flash lamp (Speedotron 4803)

I wired up a high-power photography strobe light to my oscilloscope and made some measurements of the input voltage, current and light output.

Hybrid rocket engine with acrylic and gaseous oxygen

I built a small rocket engine for demonstration purposes. The engine is built from a 2" diameter acrylic rod through which I drilled a 0.5" hole. The oxygen at 80 psi or less is passed through the hole and then is forced through a convergent-divergent nozzle at the tail end. The nozzle's throat is about 0.25" and expands to 0.625". I lit the engine by inserting a burning cotton swab (with wooden stick) while a small amount of oxygen was flowing. The acrylic catches fire very easily in a pure oxygen environment. The engine can be throttled and shut off completely, which is a major benefit to hybrid engine designs. Solid-fuel rockets cannot be throttled or shut off, which makes them difficult to control.

Viewing an active electronic circuit with a scanning electron microscope

I used my DIY scanning electron microscope to view a 555 timer circuit while it was powered. The circuit is a simple oscillator with a very long time constant to make the changes easy to see. My plan was to view the silicon die itself, and hopefully discern changes in its internal circuitry as the oscillations occurred. As it turns out, I was only able to "see" the charge of the electrical wires going to the chip socket. There is likely a clear oxide layer that covers the silicon die, and needs to be removed with hydrofluoric acid in order to use the SEM to inspect the die itself while powered.

First test with eBay x-ray tube

 I found an X-ray tube on eBay and fired it up with my Spellman high voltage supply. I ran the tube at about 35-40KV at 180uA. This required a filament current of about 1.5A at 2.5V DC.  With the room very dark, I could clearly see the phosphorescent screen glowing green. It wasn't bright enough for my eye to discern details in the X-ray images, but the camera with a 4 second exposure at f/5.6 and ISO400 was perfect. I took some pictures of various electronic components. I also X-rayed a dead, dried-up bumble bee, and it produced no image at all! The X-rays completely penetrated the insect without any visible absorption. I should have turned down the anode voltage, but I didn't think of this until after I threw away the bee.
The tube is a Nago GFH2-0.3-85-60

First test with 4.8KJ xenon flash lamp (Speedotron 4803 strobe light)

This video shows my entry into the world of high-intensity flash tubes. I was inspired by the work done by the famous Doc Edgerton who built a strobe system for nighttime aerial photography. I've heard the biggest system he built was somewhere between 50 and 75 KJ per flash -- the power needed to illuminate the ground from 1000 feet in the air!

The system in this video is a Speedotron 4803, which delivers up to 4800J per flash. Photographers use the units watt-seconds (Ws) to describe the energy in each flash, which are the same as Joules. I plan to add capacitance to the bank in order to increase the total discharge power, but the voltage may also need to be adjusted since the higher power flashes also tend to require higher voltages. I'm also planning to try different xenon flash tubes, which are capable of more intense flashes.