Hi All,

it has occured to me that my analysis of the circuit was wrong.  I did not see that even if the pulse generator was momentarily inactive, as soon as the inversion command is clocked through the delay flip-flop, the EX-ORs will flip with full voltage stroke.  This can be considered a glitch and will mess things up.

So I am now back to the beginning where the task appears to be difficult.  I know exactly what I want to do, but the schematic to achieve this is still out of my reach.  Only the pulses may be inverted, but not any steady-state voltage levels.  Not easy to see a solution at the moment.  Back to brain storming.

Regards, Earl

Hi All,

I have been busy cleaning up the "big mess" in my laboratory and workshop, and this will continue to take some time away.  Want to make another shelf and having some trouble how to fasten it to the wall.  You all probably know that "big messes" have a tendency to avalanche unless they are cleaned up and organized from time to time.

As you remember, I had this idea to use both outputs of a flip-flop, each going to an opposing excitation coil.  I found out that this meant reversing pulse polarity during rotation just like the commutator does on a DC motor/generator.  The circuit I devised did invert pulse polarity, but also inverted the base signals of Vdd and Gnd.  This glitch would always happen unless the pulse length would be increased until it is 50% square wave, at which point the glitch would happen at the correct time.  However, I don't want to be fixed to a square wave where the pulse width varies with frequency.

I have been brain-storming about how to find a solution to this problem and although possibly with a tri-filar coil and switching I could do it, I have come across another idea where switching polarity is not necessary.

This idea is that the Q and Q/ outputs go to a balanced transmission line that is wound around 90 degrees of the core.  Each coil is identically wound to the others.  One thought is that the coil could be distributed around the full 90 degrees, ending just under the start of the next coil.  Then the pulse width would be adjusted until the pulse ends just as the pulse beginning edge reaches the end of the transmission line.  Now as the frequency input of the quadrature-generator shift-register changes the pulse repetition rate changes, but the pulse widths always stay the same.  Each coil is excited in a rotary fashion at exactly 90 degrees.

By using a pulse width of 10ns in a rat race, the field would be rotating at about 1.5 billion RPM.  Here is where my traditional brain half gets in trouble with the RE brain half.  I can see where the 10ns pulse travels down the transmission line of about 3m, reflects from the open end and returns to the excitation source in the correct phase to get whacked again at just the right time.  It seems most of the field would be between the two conductors of the transmission line.  There would be relatively little current because the transmission line is voltage fed.  My big question is whether all this happening in an open-ended transmission line accomplishes anything?  Four of these excitation devices are arranged in physical and electrical phase quadrature.  I can easily see that a single-wire arrangement with opposite coils being excited in a dipole fashion from Q and Q/ will cause an electrostatic field to become a rotating electrodynamic field when using phase quadrature.  In effect this electrodynamic field is no different than an electric charge orbiting the nucleus and causing a strong magnetic field.  But will this also happen when using 4 balanced transmission lines in phase quadrature ?

The general idea would be to use a 74HC164 shift register to do the quadrature phase shifting, which drives D-F/F pulse generators.  Either these F/F outputs drive the transmission lines directly or the voltage level is boosted by a dual FET driver using both drivers for each segment.  Another option would be to follow the FET drivers with FETS driving a tri-filar transformer.  One winding for the FET and the other two to drive the transmission line.  In this case, it would be better engineering to add a balun to interface the unbalanced FET switch to the balanced transmission line.  This could boost the voltage shock up to 1 to 4 kV.

I am also thinking about using transistors or diodes in a pulse avalanche fashion to generate HV pulses with rise/fall times in low ns or even ps range, but there would be a lot of engineering to do since avalanche pulse generators are very phase unstable.  The pulse repetion rate would probably top out at 10-100 k pulses/sec.  I don't think I will put much time in this since FET transistors are so much easier and the engineering is routine.  Depends on whether or not lower voltages work well with sharp rise/fall times at thousands, millions, or billions of RPM.

Regards, Earl

Hi All,

I have managed to invent a new way to mount shelves to vertical metal supports, so I finally finished installing the last shelf in the electronics laboratory.  In next next days, will continue to clean-up and organize.  Since I will be leaving for the FE congress in Switzerland this week, I won't be able to get that much done.  I'll report if I see anything interesting at the congress.  Erfinder, who is well-known and appreciated here at OU.com will be giving a talk.  I am sure it will be interesting to meet him and chat in person.

I had another idea for symmetrically exciting a coil, which is attached, but my gut feeling is that my previous idea of an open-ended transmission line is better.  I can't think of any other ways to excite a coil, both symmetrically and balanced.

I am totally convinced that very rapid rise and fall times are extremely important.  Less important, but perhaps crucial is a small pulse width.  I have various parts that will arrive in the near future, and I may just take a detour to investigate the behavior of diodes and transistors in avalanche breakdown mode.  If it is not too much of a detour, I would be thrilled to be able to create pulses of a hundred or two hundred volts with rise times and pulse widths way below 1 ns, say 350 ps.

This implies that I can measure such pulses and my present Textronix scope probes, even if they are rated at 500 MHz do not please me.  The only ground I have is a short ground lead.  If I take the tip attachment off, there is no ground ring surrounding the probe tip, as I have had with other scope probes.  I think I will fabricate myself some HF scope probes using SMD components, where I have the scope tip surrounded by a ground ring that also has a small probe.  This will give me very short tip and ground leads.  With only 2 resistors and one or two capacitors, I think I should be able to design and build my own high-quality 500 MHz 10:1 scope probe.  It may not be a beauty, nor have exact DC calibration, but it should have good HF fidelity and shorter than short ground lead.

Earl

As you raise potential, you can narrow the pulse width and still get more response. So your reasoning is valid.

Bob

I have returned from the Swiss FE conference, which was very interesting even though I did not see any OU devices with certainty.  One Belgian M.D. showed up with a new way of placing magnets and coils in an AC alternator and was claiming 4:1 OU, although his measurements were not scientific enough to give a conclusion.  I liked his original way of thinking.  He was a very funny presenter, quite a live wire and had everyone laughing a good part of the time.  Mike Bradey from Prenderev canceled his Saturday evening talk with demo at the last minute.  There were 50+ people who had paid him money and wanted to have a serious talk with him.  My opinion now is that he is a bla-bla.  I had an after hours discussion with Erfinder and others that lasted until 02 AM.  In general, it was a very interesting conference, and I would not have wanted to miss it.  Oh, there was a German researcher that built an uni-polar machine out of two alu wheel rims.  He made the interesting discovery that he could mount the center and the rim on ball bearing and pass huge currents through the bearings with absolutely no negative effects.  He was passing currents like up to 16kAmps through the bearings. And also very high RPMs.  He said he had an anomaly whereby at high currents and high RPMs he could get in a fraction of a second a speed-up runaway.  There was a very interesting talk by an older German fellow who worked on the VRIL flying saucer project and also with Hans Kolar.  His brain and memory were still sharp as a needle.  I am fluent in German so the conference was no problem for me.

So now I am back and have to finish cleaning up my electronics lab.  Unfortunately, my notebook LCD decided to have problems, so I am limping along on a replacement that consumes many times more power.  Since I am 100% solar powered, this limits my computer time, especially on cloudy days.  I have ordered a new notebook to use while the defective one is repaired.  As soon as my lab is operational again, I will continue my research with narrow, fast pulses.  Will investigate transistors and diodes in their voltage breakdown region.  If a transistor is just under its breakdown voltage and is pulsed on its base, it can avalanche on this sync.  In order not to destroy the transistor, a choke or resistor is used to supply collector voltage to limit breakdown current.  The collector current is provided by a small capacitor of roughly 2 pF and the emitter goes to ground through a 50 Ohm load.  Will try both bipolar and FETs.  I have some HV avalanche rated diodes so will also try these.  I figure if the diode is just under breakdown limit and I hit it with a pulse that brings it into breakdown, then I can control the pulse timing.  Another idea is to use the standard "short the Vsupply to ground through a choke coil" and feed the back EMF to the avalanche breakdown circuit.  I.E. don't use a standard HV pulse directly, but pass it through a shaper circuit consisting of an avalanche device.  Instead of limiting device dissipation by keeping the collector or drain capacitor low, this idea would use pulse width modulation to limit the joules dissipated in the shaper semiconductor.  I believe this detour could pay big results if the circuit could provide HV pulses of 50 to 350 ps rise/fall times.  Will be calculating the SMD R's and C's needed for a 10:1 probe and home-brewing my own 1 GHz scope probe, which will be needed for such fast pulses.

Earl