https://www.posetteforever.com/viewtopic.php?f=25&t=1342&p=19825#p19825 ----------------------------------- Visitor Friday, 25 March 2005, 04:51 AM ----------------------------------- Two years after I graduated from highschool, I was in college I was going from my office to the cafeteria to take a break before checking in at the computer lab to see if my job had ran yet, then back to the office. (Point of explaination, I was student at the college and I had a part time job there also. Computer jobs, in those days we used puch cards and printouts rather than video terminals). On the way, I encountered one of the students from my highschool. He was at the time a student in the highschool and was visiting the college campus to determine if he wanted to become a student there after his graduation. He was not one of those students who was in the class were I gave that presentation. When I mentioned that I was going to the cafeteria to get something cold to drink, he looked a little strange and asked me, If I was going to be drinking water. When I told him that I was going to get a half pint of milk, he looked relieved. I asked him, why whats wrong with water? He replied, "What? Don't YOU know?". That is when I learned that they were STILL telling each other the story of that presentation! On the other hand, there was another presentation that I did in highschool, it was actually more like a lecture and demostration. This one had to do with communications via various segments of the electromagentic spectrum and other vibetory medium. I had already been teaching myself electronics for years by that time so there was no real experimentation involved. For the demonstration, I set up a chain of different electronic devices that I had made on prefboards, so they were not pretty, but they worked. Starting with a simple free power radio reciever made from one salvaged variable capacitor, one diode, and one aircore coil. I wound the coil on an empty cardboard tube that was to core of a roll of toilet paper. Having to battery or other power source the radio was not very loud. I tuned it to a loud local broadcast radio station, then proceded to create a chain of electronics devices and mechanical devices that the sound passed though. In the chain the audio from the radio was passed though various trasmission mediums, such as: a magnetic field from by two home made coils brought in proximity to create a transformer; visible light by an led and phototransistor a few feet away; infrared same as the visible light; wood by a speaker rigged to be sound proof except in one direction and that direction being the top of a wooden bench and picked up a few feet away by a microphone (actually another old speaker that I modified) attached to the bench; by water via two old salvaged speakers rigged to work as underwater transducers placed suspended in water at the opposite ends of an aquarium. Combined that with proof of how the vibrations and transducers worked. While by the final stage the quality of the sound had degraded consideribly, it was still understandable. About six months latter, what do you think was remembered about this presentation? That I made a tiny disco strobe light blink to the music from a crummy sounding radio. After summer vacation, I overheard one returning student telling a new student about the presentations we have to do, and described it that way. He used it as an example of how people can just mess around and do nothing and still get credit. But the water, they remembered even after I was gone from that school! Pangor