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Old 08-28-2009, 09:22 AM
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Aaron Aaron is offline
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Join Date: Feb 2007
Location: Washington State
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Tuning the circuit


For tuning, focus on the dc value at the shunt compared to the rms at the shunt. Have both readings on screen at same time. It isn't necessary to try to get negative like I did. If heat is your goal, you need positive wattage flowing into the circuit to do that.

That one piece of advice that originally came from Rosemary, about focusing on dc/rms comparison, will save you LOTS of time from trial and error.

You want the biggest spread you can get so that the dc at the shunt is much, much lower than the RMS at the shunt.

The bigger the spread, the better your efficiency and COP. The dc reading, the lower it is, the more balanced your waveform is above and below the ground level.

At lower DC readings, you'll have less heat but will probably be much more efficiently produced than the control. If you want more heat, you may need more DC at the shunt but make sure the circuit is tuned so the RMS is way high.

It is a waste of time to do any draw down test or otherwise if those numbers aren't far enough apart. Once you have your best settings by doing that and you could analyze the power like I did with the data dump, but then do the draw down. That saves lots of time so you won't be doing drawdowns on trial and error basis. The drawdowns take a LONG time. Good to have 2 people that can watch it around the clock.

When tuning your dials, look at the waveform and just go through every combination you can between the 3 pots just for the learning experience. You will get the feel for how to even out the waveform above and below.

There is a very profound implication here about the balanced waveform. Everyone is programmed to see a positive on pulse then a spike that is a very narrow width - it appears to have been widely assumed that the collapsing magnetic field

Did anyone ever say or prove that we can't WIDEN out its time frame in the negative zone? I don't think so. The more you can widen it out, the less positive there is of the waveform and that brings it towards balance.

Of course the amplitude reduces but the area under ground area starts to mirror the positive side. And you can then get more under than over.

At this point, I see a limit as to how much negative it can go with this switch. There may be other switching methods that can bring it more negative - I'll leave it to the open minded EE's or engineers to come up with something for that.

With my parts, I'm limited to this basic circuit that has been posted for years but with a few minor modifications.

And use liquid lead acid batteries and not gel cells.

And 10 turn tuning pots in the right ranges.
Aaron Murakami