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Author Topic: Circuit sj1. Terse and Technical only.  (Read 167554 times)
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PhysicsProf,

Ex has pointed out K1 (coupling). This, and the circuit values of the secondary components, will have an effect upon the result frequency compared to the results of the web calculator you used.
An increased secondary load will increase the frequency since this decreases the primary inductive impedance reactance (more appropriate).

I would expect the measured frequency to be a bit higher than the web calculator says.

When all of these factors are entered into the sim the simulator should reflect what you are seeing, as far as frequency goes. I'll not speculate on the rest.
   
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Professor,

I'm currently on vacation. When I return, I will likely be building the oscillator Rose is currently working on. Glen has sent me some additional MOSFET's, so I can build the full version. I'll be doing some testing on that circuit.

Hopefully the sim for your circuit can be developed to produce results closer to what you are seeing. That way you'll be able to probe anywhere in the circuit and perhaps determine where the differences are between the sim and bench unit.

Regards,
.99

Good luck on that Rose oscillator testing.  And have a good vacation ;)
I'm more interested in real replications of the sj1 circuit than sim runs, fun as they are, and appreciate exnihiloest for the schematic-drawing.

I'm consistently double-checking things.  The Pout/Pin results seem quite solid, results given above. 
About the "opposing LED's" however, I double checked the yellow LED which I had not used before -- and bottom line is that I got the direction wrong for it.
So I had two LED's in series in the SAME direction...  nothing surprising there that they both lit up.  Again, that was not the basic circuit in any case (was just for fun and learning) and in no way affects the measurements done on Pin and Pout given.
   
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Thanks for the change, .99.   Any chance you'll do a replication of this circuit, and tests including Pout / Pin?

In my 2nd post above, I noted good results with Rr = 3.1 ohms.
...

I have added Rr and replaced the standard diode by a low power LED from the LTspice library. It doesn't change much. We see that the frequency is less than 100 Khz, which is compatible with the time constant 1/Rb*Cb.
See first trace in: FEosc-traces.png

Then I have considered the capacitance between Lb and L0 due to their proximity. In real life, there are always parasitic capacitors  :(. So I added Cp=20pF connecting the two coils.
The simulation seems much more realistic, see the second trace in: FEosc-traces.png.
The time constant 1/Rb*Cb still plays its role, but modulates a new signal due to Lb/Lo/Cp ringing (around 2 Mhz).

Then I replaced the ideal NPN by the LTspice model of 2N2222.
Now the time constant 1/Rb*Cb does no more appear except for the first burst.
See the third trace in: FEosc-traces.png

Finally I visualized the power and the energy (COP<1, no surprise). The output power is calculated from the product of the voltage available at the emitter by the current passing through the LED/R0/CSRout.
See the final circuit and the traces of the power in FEosc-Power-Energy-schematics.png

For those not familiar with LTspice, one can get the energy or rms values by a ctrl+click on the title of the trace in the simulation window.
LTpsice model is in FEosc-2N2222.asc.

May be I will duplicate the circuit if time permits.

   
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Thanks again, XN.
So the SIM can't get the Pout/Pin that we see on the Tek 3032 -- as you say, not surprising that the SIM can't get it.

  I wonder if it can do another task.  With these conditions:
Rb = 2K
Rr = 0
D = 1n4148 diode
Vin = 2.6 V
10,000 uF (16V) cap IN PLACE OF Rout, oriented as shown in schematic below.

Then, I measure with a stop-watch that the Co cap charges from 0 to 7 volts in 2.5 seconds, as soon as I turn the circuit on.  Can the SIM get any thing like that?

I thought this was a significant result.  Eout can be calculated from E = 1/2 CV**2.

I'm open for suggestions on determining Ein with this Cap-charging test.  Remember that if I connect a charged cap  to an equal C uncharged cap, I lose half the energy in the process, so I' rather not use a charged-cap as the input Ein. 
I also bought a few high-C caps, hoping to use these in lieu of a battery for Vin.  BUT -- I found that they "leak" somehow, rather steadily.  The 10,000uF caps hold the charge better, but I run into the problem alluded to above ( if I connect a charged cap  to an equal C uncharged cap, I lose half the energy in the process...).
   
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I put the conditions:
Rb = 2K
Rr = 0
D = 1n4148 diode
Vin = 2.6 V
Cout = 10,000 uF (16V)

I have had to reduce the calculation step otherwise the simulation fails. With short steps, the sim is very slow (each HF period must be sampled in many steps and there are more a million periods/s). I must end the sim after around 10ms.
Nevertheless the sim shows that the capacitor charges very linearly at 6.5 mV/ms and the power provided by the battery is a stable 272mW.
After 1s, we can estimate that the sim would give a wasted energy of 272mJ and the capacitor would be charged at 6.5v, storing an energy of 0.5*C*U2 = 0.5*10-2*6.52 = 211mJ.

A sim will never show OU (if there is no bug :-) ).
I suggest that you build a second strictly identical circuit but no battery, and you power it with the capacitor of the first one. A 2.6v zener in parallel with the capacitor will limit the voltage at the same value as the battery.
If the second circuit can also charge its own capacitor to 2.6v, there is suspicion of OU. Then to be sure, measure the currents in the Csrin of the 2 circuits. If they are equal, or if the second one is more than the first one, there is clearly OU, and to loop the two circuits without the battery should be conceivable in a next step.

   
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  I'll try your suggestion, XN, or equivalent...  Again, just discharging a cap into a 2nd equal cap will necessarily involve a loss of half the initial stored energy.  (Doing the math, E = 1/2CV**2)  But I'll give your idea a go to see what happens, experimentally.  I have several errands this morning first...

Meanwhile, could you kindly post your circuit diagram for the above from SPICE?  thanks for doing all that work, BTW -- very helpful.
   
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« Last Edit: 2011-05-27, 05:16:39 by duff »
   
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(deleted per request of person to whom I was replying)

  Thanks for doing the SIM, though -- these can be a lot of work, and its a learning opportunity for us all.
« Last Edit: 2011-05-27, 05:41:06 by PhysicsProf »
   
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« Last Edit: 2011-05-27, 05:17:18 by duff »
   
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This is interesting...  Glad we agree on the use of the MEAN rather than RMS.

I like your positioning of Rr in this instance also.
« Last Edit: 2011-05-27, 05:46:32 by PhysicsProf »
   
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« Last Edit: 2011-05-27, 05:17:43 by duff »
   
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(deleted per request of poster to whom I was replying)
« Last Edit: 2011-05-27, 05:39:41 by PhysicsProf »
   
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« Last Edit: 2011-05-27, 05:18:07 by duff »
   
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« Last Edit: 2011-05-27, 05:18:31 by duff »
   
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 I'll try your suggestion, XN, or equivalent...  Again, just discharging a cap into a 2nd equal cap will necessarily involve a loss of half the initial stored energy.  

The loss of half the energy is true only when the capacitor is charged from a voltage source, not true when it is charged from a current source. When a magnetic field through a coil collapses, the coil acts as a current generator, charging a capacitor without losses (allowing for example LC oscillators weakly damped in spite that the capacitor is periodically charged and discharged from the coil).  We see that it is the case here, because the capacitor is negatively charged: only the coil can provide such a current. So this point is not worrying.
There is an equivalent way to charge a capacitor theoretically without losses and from a voltage source, which is named "adiabatic charge". It had been studied by IBM to reduce the consumption of VLSI circuits due to the gate capacitance of MOSFETs: the voltage source must be controlled. It is increased slowly and maintained very near and just above the capacitor voltage.

Quote
Meanwhile, could you kindly post your circuit diagram for the above from SPICE?  thanks for doing all that work, BTW -- very helpful.

See the attachment. The Trtol parameter of the simulation (in control panel, "SPICE" tab) is put to 0.01 instead of 1, its default value.

Another point: when the capacitor is disconnected, the sim shows that the emitter of the 2N2222 is periodically at a positive voltage up to 10v (even more at the begining). We had seen elsewhere that this transistor presents a negative resistance when reverse polarized around 6v. I had checked that LTspice fails in simulating this negative resistance. In the circuits with negative resistance, the transistor base is disconnected but I had also tested the negative resistance with the base connected in some ways. This point could be of interest in the functioning of the real circuit.

« Last Edit: 2011-05-27, 10:13:30 by exnihiloest »
   
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In an effort to optimize Rb again (now looking at 2ms of data), I step through standard values of resistance from 51K to 20Meg.
The highest COP resulted with Rb = 3.3Meg which gave a COP = 4.1.
Frequency of 1.3MHz.

t2: v(vout)=2.0v AT 1.49641e-006
t1: v(vout)=2.0v AT 7.29945e-007
freq1: 1/(t2-t1)=1.30469e+006
ir1: AVG(i(csrin))=-1.20317e-005 FROM 0 TO 0.00209
ir2: AVG(i(csrout))=-1.01898e-005 FROM 0 TO 0.00209
ir3: AVG(i(rr))=2.22216e-005 FROM 0 TO 0.00209
vout: AVG(v(vout))=0.00748531 FROM 0 TO 0.00209
vr1: AVG(v(vcsrin))=-1.20317e-005 FROM 0 TO 0.00209
vr2: AVG(v(vcsrout))=-1.01898e-005 FROM 0 TO 0.00209
vr3: AVG(v(vrr))=2.22216e-005 FROM 0 TO 0.00209
cop: ( (vr3*ir3) + (vr2*ir2) ) / (vr1*ir1)=4.12836


AVG(v)*AVG(i) is not equal to AVG(v*i).
You must use instantaneous values of u*i and integrate the product over time.
(LTspice obeys Kirchoff's law: sum of currents in a node must be zero. So it can't show COP>1).

   
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AVG(v)*AVG(i) is not equal to AVG(v*i).
You must use instantaneous values of u*i and integrate the product over time.
(LTspice obeys Kirchoff's law: sum of currents in a node must be zero. So it can't show COP>1).

Thanks
   
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I would like to thank Duff for his input.  And if there was a mistake, so what?  we are here to learn.  And to probe the frontiers of energy research.  Not likely we'll do this without a small mistake, or two. 

We don't expect LTSpice to tell us when a device is "overunity".  IMO, only experiments can do that -- experiments including careful measurements on Pinput and Poutput.  I agree with exnihiloest that a self-running device would be a compelling demonstration, if it could be replicated and done repeatedly.  Repeatability is the heart of good science and progress.  Such a device should also allow us to determine the source of the "anomalous" incoming energy.

Sterling Allan came by yesterday and videotaped some of the work I'm doing...  So you'll be able to see more of the device and results.
Traveling today and then a long trip next week -- cheers, then.

   
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Thanks

Think nothing of it. I saw that you used "AVG", a key word that I didn't know. I just found it now in LtSpice help. This opens me interesting possibilities. I thank you also.

   
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I apologize if these questions are stupid...

Regarding your CB - LB tank circuit.
90uH and 151pF = 1.37MHz (using my web LCR calculator)

151pF seems like a odd value so I was wondering what are your constant items and what are variable?

90uH is most likely constant (could be varied with +/- windings)
Was 151pF constant or a variable capacitor?
Is 1.37MHz a constant value you were seeking or just the end result of using those 2 components?

Thank you for your time,
DonL

   
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I apologize if these questions are stupid...

Regarding your CB - LB tank circuit.
90uH and 151pF = 1.37MHz (using my web LCR calculator)

151pF seems like a odd value so I was wondering what are your constant items and what are variable?

90uH is most likely constant (could be varied with +/- windings)
Was 151pF constant or a variable capacitor?
Is 1.37MHz a constant value you were seeking or just the end result of using those 2 components?

Thank you for your time,
DonL

Good questions, DonL.  151 pF is what I had several of, readily available -- a constant cap.
Yes, once the toroid was wound, it was about 90uH and could be varied with +/- windings, but left as a constant.
The combination in a tank circuit gives 1.37 MHz, as you say,  the end result of using those 2 components.
I should add that sometimes the scope has difficulty picking out the frequency... until I properly adjust the trigger (sometimes, I don't bother with that).

   
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@PhysicsProf,

Congratulation in making my circuit,  the one I made you aware of at 2011-03-11, 23:10:17, go over unity.
( http://www.overunityresearch.com/index.php?topic=764.0 ) I'm really pleased to see that it was possible
to tune my circuit design in the way you did. Keep up the good work. :-)

Groundloop.
   
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To
Ro 9.8K
Rr 3.1ohm
Rb 2K
No  Co
I(t) measured over 1ohm CSR's
Then see Tek3032 attached, Pin left red waveform, Pout right.

@PhysicsProf,

First of all, congrats on your progress! But I think we should also be very careful with the results. I noticed that the frequency shown in your picture are dramatically different (3.926MHz on the Pin measurement, 37.10MHz on the Pout measurement). Therefore I am wondering if it is because the circuit is so sensitive that by putting the probes at different places, the whole thing changed. If that's the case, your measurement might make little sense...

I suspect that the frequency should be the same on both the input and output side....but I could be wrong.  Therefore I think it would be great to measure the frequency on both input and output sides at the same time. Here is a possible way of measurement: put the ground at point 4. Then one probe at Point 2, another probe at Point 5. This way we can measure if the frequencies on both sides are the same or not.

lanenal
   
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 Thanks for this, exnihiloest...

  In my head, I get about 100 KHz for your simulation results... which indeed is far from the 1.4 MHz observed.  

Its late, and I need to retire, but I've checked the frequency for the Lb-Cb tank circuit... which controls the transistor gating, clearly.  I get 1.37 MHz (see attached), which agrees with observed.
  I'm surprised the sim is so far off from the observed freq.
Thanks again!

I noticed exnihiloest used Rb=51K in his schematic, and got roughly 100KHz. But in your second post, your value was Rb=2K. When I changed to Rb=2K in exnihiloest's schematic, I got 11/7 = 1.57 MHz, which is also close to your 1.4MHz observation...

lanenal

P.S.: when I changed the "K1 Lb L0 0.9" to "K1 Lb L0 0.5", Kb=2K, I got 1.38MHz with simulation.
« Last Edit: 2011-05-28, 12:01:11 by lanenal »
   
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I built the real circuit yesterday. I have some problem for it to work. I was unable to make oscillate a 2N2222A.
With a transistor better designed for HF frequencies, such 2N2369 or 2N2218, the circuit oscillates but at frequencies around 80 Mhz! Obviously this frequency is not related to L and C values. I tried with 2 different toroids and coils, and I got similar results. Moreover one of the two coils can be reversed and the oscillation remains the same.
The only result according to the simulation is the "modulation" of the HF signal by a signal of much lower frequency, linked to the time constant RbCb, only when Cb is exceeding a certain threshold value (that I don't know, I used a variable capacitor).
For me it is a variant of a Colpitt's oscillator, so I don't see what is wrong.   :(

   
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