Yes, I've seen the videos. Operation in a vacuum would not prevent the induction I mentioned earlier. The only way it would is if the vacuum chamber was also built to redirect external magnetic fields away from the interior. Faraday cages do not shield against static or slowly changing electric and magnetic fields. Ex: A compass will work just fine inside the best Faraday cage. A magnetic shield enclosure or any Faraday cage have their limitations. I worked as a SIGINT op during the cold-war. Believe me when I say, very few invoking the names of these devices really know how to build or use one correctly. On the capacitor powering an LED question...... I once ran a micro-power multi-vibrator powering an LED for several months off of a 68,000 uF 1000WVDC aluminum electrolytic cap after charging it to full operating volts for 60 seconds and discharging it for 10 seconds with a DC contactor. I don't remember how many volts it recovered to initially but it was high enough that a large zener and dropping resistor were needed between the cap and the LED driver circuit. After some minutes the voltage stabilized in the several hundred mV range while powering the LED circuit through the jumpered zener dropping resistor. It ran until I needed the cap for another project. I chalked the performance up to bad dielectric absorption, detector functions of the zener and ridiculously long jumpers. I didn't bother with a Faraday cage. I'm hoping this disc is an improvement over my results. It looks like a vast improvement In addition to hoping for measurements made with temporary connections I would like to see how the voltage builds after it was shorted for 10 seconds.
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