"I'm just playing around...I mean," I quickly corrected myself, "I'm conducting an important experiment!"
"And what would that be?" he asked eyeing my setup.
"I am graphing the Hodowanec Offset Voltage on a capacitor.
"The who, the what?" he crossed his eyes and looked puzzled.
"The Hodowanec Offset Voltage," I repeated in italics. I placed another capacitor and digital multimeter on the workbench so as not to disturb the ongoing experiment. "First I am going to connect a one megohm bleeder across this 38,000 MFD computer grade capacitor. What does a bleeder resistor do?" I quizzed.
"It discharges the capacitor relatively quickly after power is disconnected from a circuit," Mike recited correctly.
"Good boy!" I said as I took a pretzel nugget from the jar on the bench and popped it into his mouth. "Now I am going to connect the multimeter across the resistor-capacitor combination and set it to its most sensitive DC range."
"Hey!" Mike exclaimed as I connected the meter. It's still charged.
"We can fix that easily enough." I picked up a screwdriver and shorted the capacitor.
"That did it," said Mike as the meter dropped to zero.
"Now watch what happens when I remove the short," I said laying down the screwdriver.
"Nothing," Mike observed and turned his attention to the jar.
"It's a good thing you're not a doctor," I observed. "You don't have any patience. Serves you right!" I added as Mike choked on his pretzel.
"Now look at the meter," I commanded as the display indicated one millivolt.
Mike came back from getting a drink of water at the laundry tub faucet as the reading climbed to two millivolts. He studied the simple setup for hidden wires. "Where's that coming from?" he asked as the reading flickered then stabilized at three.
Greg Hodwanec was the first to measure the self-voltage of capacitors. He believes it is caused by gravity." I lectured.
"Is it?" Mike demanded.
"I shrugged my shoulders. "I don't know. That's why I spent the money on this multimeter with a computer interface and am letting this computer run for days at a time playing havoc with my electric bill."
MIke walked over to the computer and looked at the screen. "So what am I looking at?" he asked.
"A computer screen," I replied off-handedly.
"Ask an intelligent question..." he snorted.
"The Hodowanec voltage contains many, many frequencies," I explained. "With such a large capacitor and bleeder resistor I am measuring a very slowly varying DC voltage. I call it the Hodowanec Offset Voltage. I have the program set to take a sample every four minutes and plot it on this graph. The vertical scale is calibrated directly in millivolts and the horizontal sweep is two hours per division or thirty-two hours total."
"Watching that move is like watching my spice garden grow," commented Mike sagely.
"In the experiment I am using a 27,000 MFD capacitor from my junkbox and a one megohm bleeder resistor. After I started by shorting the capacitor, the voltage slowly rose to the four to five millivolt area and has stayed there with only minor variations."
"What did you expect to find?"
"In checking at random times during the day in previous setups before I sprang for the new meter, I have seen the voltage anywhere from zero to over a quarter of a volt. I was hoping that the graph would allow me to correlate the variations with the positions of the sun and the moon... or something."
"So what caused this sharp drop?" he questioned pointing at the screen.
" That's the one correlation I have made so far. This plot starts at midnight so, at two hours per division, that makes it eight o'clock in the morning. That is when my programmable thermostat warms the house from sixty degrees to seventy degrees. I noticed that drop several days in a row. One day I set the thermostat up to seventy at seven in the morning and the voltage dropped at that earlier hour.
"So the temperature is affecting the voltage?" queried Mike.
"It seems to be." I agreed, then added, "So any serious experiment will require a constant temperature environment for the capacitor. I am already planning to build an insulated box with a light bulb heating element and a thermostat inside."
"When you're done with the experiment can you hatch some chickens for me?" Mike asked casually.
I gave him a foul look.
"It's yust a yoke," he crowed.
"Well, it layed an egg," I cackled in return.
"What's that, a mountain range?" asked Mike as he stared at my computer monitor a couple weeks later.
"That's a new Hodowanec Offset experiment I just finished last midnight," I replied proudly. "Do you remember how the 27,000 MFD capacitor appeared to follow the temperature in my house?"
"Yup, I remember," said Mike.
"Well, I was trying this blue 38000 MFD cap when I noticed something really odd..."
"Are you sure you weren't looking in a mirror?" joked Mike. At least I assume it was a joke.
"I had the meter across it and was checking the voltage occasionally when I noticed that it had gone negative," I continued ignoring him. "I couldn't wait to run a graph so I fired up the old clone, set the vertical axis for zero center and the horizontal for three hours per division so I could get an even two-day run. And that's the result," I said directing his attention back to the screen.
"It's pretty nifty," commented MIke agreeably. "What's it prove?"
"It seems to follow the temperature changes even more closely than the other. The graph starts at midnight. That's when the thermostat switched to sixty degrees. You can see the voltage rise as the house cools." I pointed to the graph. "Then at eight in the morning the thermostat switched back to seventy and the voltage promptly started to drop. In addition the cycle repeated almost identically the second day."
"Didn't we already know that the temperature affects it?" Mike questioned.
"Yes we did. And this run confirms it. But it's the fact that the voltage goes both positive and negative that I find fascinating," I said fascinated.
"Oh, yeah. I can see that," Mike yawned.
"No, you can't see it," I corrected him. "That's what makes it so interesting. If whatever is causing the voltage can make it switch polarity I would expect a discontinuity, a bump, as it goes through zero. But there isn't one!"
Mike stuck his face close to the monitor for a few seconds. "You're right. It's perfectly smooth," he observed. Then he sniffled and pretended to wipe his nose on the screen. One has to learn to ignore these displays. "How come?" he asked admiring his still clean sleeves.
I think there may be two effects operating," I opined. "One is trying to hold the capacitor at a steady voltage in one direction while the temperature change is having a greater effect pulling it in the other - dragging it right through zero and out the other side.
"So your whatsit is making it negative and the cold is making it go positive?" he queried.
"We don't know that. The whatsit," I corrected myself. " I mean the unknown factor, could be holding it positive and the heat could be pulling it negative. We don't have enough information yet to tell."
"So how do we tell?" he asked reasonably.
"I'm going to have to sleep on it," I told him.
"You go right ahead," he quipped. "Personally, I'm going home and sleep on my bed. It's not so lumpy."
Updated 04 JAN 2001