Bogging Down the Bedini

[earthbound0729]

Carroll, thank you for your earlier congrats.

are the ends of the diodes soldered together or just twisted together?

All soldered. I have 2 soldering tools: a heavy gun and pen type for finer work, but not too fine.

Some good things I noticed with my setup last night was that neither the coil nor the transistor actually warmed up. After everything had been running for an hour, they were cool to the touch, which did not seem normal since there is an applied voltage and current of some value running through that system. Plus, not to mention the field collapses.

I have to assume you were measuring the AC with a meter.

Yes.

You really need a pot in the trigger circuit.

Got one I just soldered leads to a few nights ago. Never knew I would need it this soon.
Most circuits including Daftman's show the middle lead soldered or connected to one side, so I essentially end up with a voltage divider with no real off point. I don't know that that is essential per se in this circuit, but I also know if I connect 1 side to ground and the other to positive I can actually control the voltage output better using the middle lead as my hot wire. If the potentiometer is used merely a a variable resistor then the 2 wire setup should be fine for this experiment. I'll await your clarification on that Carroll.

My Understanding of the Dual Battery Circuit by just looking at the circuit design-please make any corrections.

1. The trigger coil never is actually energized by any battery. The base of the transistor receives its momentary power from the collapse of the magnetic field after any magnet passes by the iron core. According to the Bedini layout, at least, the assumption is made, and then proven, that this collapse and then transfer of Radiant energy must be away from the Top of the Trigger coil down through the outgoing wire into the resistor and is prevented from going through the reversed diode into the negative of the run battery, thereby forcing it into the Base of the transistor.
2. The main coils seem to have 2 components on the mulitifilar wind.
     a. The first component is when the electromagnetic portion occurs as soon as the Main coil(s) are (is) energized by the Run battery (Mine is setup in Push mode, ie repelling the magnet after the pass) as soon as the Trigger coil field collapse energizes the Base of the transistor.
     b. The second component involves the magnetic field collapse of the Main coil(s) which must also send the Radiant spike into the Charge battery Negative side-apparently-I am not sure here. I think this is in line with Bedini's teaching.

I realize all this is happening at the rotation speed multiplied by the number of magnets in rotation on the rotor.
I'll await any updates and corrections.

dave

[citfta]

You are pretty close but not quite right.  The magnet passing the coil starts the process by inducing a current into the trigger coil.  If the coil is connected correctly that current will be positive on the end going towards the base.  When the base of a NPN transistor is about .6 to .7 volts more positive than the emitter then the transistor will be turned on almost all the way.  Anything above that and the transistor will be on all the way but you don't want it to go too high or you can damage the transistor.  You also don't want the base to be forced too far in a negative direction and that is why there is a diode connected to the base.  The diode will turn on if the negative voltage from the trigger signal goes over -.7 volts in reference to the emitter which is connected to ground.

The positive going signal from the trigger coil turns on the transistor and current starts to flow into the power coil or some call it the motor coil.  As that current builds up it induces a current into the trigger coil also.  But in a negative direction.   If the magnets are moving too slow or the resistance is too high in the trigger circuit the signal on the trigger coil can go negative enough to turn the transistor back off before it gets the magnet kicked completely out of the way.  You can sometimes hear that high pitched whistling sound of the circuit oscillating as the coil keeps getting turned on and off at a high speed.  When the rotor gets up to speed you want to adjust the pot so there is only one pulse for each time a magnet goes by the coil.

Then as you said when the power is turned off by the transistor the collapsing magnetic field sends the spike to the charge battery but not to the negative side.  It sends it through the diode to the positive side of the charge battery and then because the negative of the charge battery is connected to the top of the coil the current completes its path back to the coil until all the magnetic field has collapsed. I am talking about the conventional idea of current flow.  Actual electron flow is opposite to the conventional idea of current flowing from positive to negative.  Just ignore this part if it confuses you.  Just remember that the diode connected to the collector of the transistor has to have the cathode end (the one with the band) connected to the positive of the charge battery.  That is all that is really important about connecting the charge battery.

The proper way to connect the pot is like this.  With the pot laying on its back so the shaft is sticking straight up, position the pot so the legs are facing you.  Now connect the trigger coil to the leg on the left.  Connect the middle leg to the resistor going to the base of the transistor.  Now when you turn the shaft you are moving a wiper that is connected to the middle leg so that it is moving closer or farther from the end going to the trigger coil.  That is how you change the resistance for the base.  Start your system with the pot turned most of the way to the left and as it gets up to speed start turning it slowly to the right and listen for the highest speed you can get.  For this circuit we don't need to wire the pot as a voltage divider.  But you are correct if you connect one outside leg to the high side and one to the low side you would have a voltage divider but we don't need that here.

You mentioned nothing was getting hot and that is the way this type of circuit should be.  It is a pretty efficient circuit and the pulses are so short there should never be any heat anywhere in the circuit.  It there is any heat at all something is not right.

For the most part you seem to have a pretty good grasp of what is supposed to happen.  Find you a copy of the ARRL Radio Operators Handbook or take some online classes to help you understand better what you are doing and what you should be seeing in your circuits.

I'll still be glad to answer any questions you have along the way while you are getting educated in electronics.  I'll leave my settings for this thread set so anytime someone posts here I will get an email and can then come see what is going on. 

Take care,
Carroll

[earthbound0729]

A couple of more things Carroll, and then I'll be off and running for awhile.

1. How many Main coil sets can be run through 1 bridge rectifier circuit since they are all firing at the same time?
2. Why doesn't the Bedini circuit show bridge rectifiers, or most any other Bedini type circuit, especially since an alternative storage or boosting system such as electrolytic capacitors do better with AC to
DC converted electricity. I imagine DC batteries would do better being recharged by dc current also.
3. So, in view of the end of my last query, should I also use a bridge rectifier to the Charge battery? And if, what would be the best way to connect it?

Thank you for all your help and time on a newbie.
dave

[citfta]

Hi again Dave,

Those are some good questions.   And you have a perfect system for answering some of them.

In regards to the question about using a bridge on the charge battery of the main circuit I can answer that one pretty easily.  If you connect a charge battery with a bridge across the power coil when the transistor turns on current can flow through the bridge and into the charge battery from the main battery if the voltage in the charge battery is pretty low in comparison to the run battery.  I do know of at least one other person who has a bridge connected that way and it also works to charge a battery.   I am not sure that it will charge any better than the single diode from the collector to the charge battery.  This is something you can test for yourself and see what works best.

Why do we need a bridge on the other non-powered windings?  That is also a good question for you to check out.  You are correct we have to have a way to convert the AC from the coil to DC before we can use it to charge a battery or cap.  But review what I posted earlier about the discharge of the coil.  When the magnetic field collapses the induced current is always in the same direction as it was previously going. 
That is why we only need the single diode from the collector to the charge battery to get a charge into the charge battery.

On the other coils that are not powered there is also a current being induced into them that is in one direction.  But we don't have either end connected to power or a transistor so we don't know which end is which.  It is easiest to just connect a bridge and then it doesn't matter.  I have not built a multicoil machine like yours so the next part is based on my experience in electronics and my knowledge of how electronic things work.

Almost any device has some capacitance like a capacitor only much smaller.  When a coil discharges into a capacitor even a very small one it will try to keep the current flowing to the point the cap gets charged to some voltage.  Now when the magnetic field is done collapsing the induced current stops but we now have a slightly charged cap connected to the coil.  The cap will then try to send the current back through the coil the other way until the cap is discharged.  This is why we get AC from a coil that is being powered by pulsing DC.  The bridge rectifier changes this AC into DC.  But it also helps to block the AC from even happening because the current from the first discharge is sent to a cap and the bridge blocks it from going back to the coil to discharge the cap.

When current flows through a diode there is a certain amount of voltage drop across the diode.  Usually that is about .5 to .7 volts. except for special diodes like shotkey diodes.  When you use a bridge the current in one direction has to go through 2 diodes to get to the cap or other load.  So a bridge causes twice the voltage drop of a single diode.

Now here is a test for you.  Take one of the extra coils and connect it with a bridge to a cap.  Take another coil and connect it with a single diode with the cathode (striped) end to the positive of a cap and the other end of the cap back to the other lead of the coil.  If the cap with the single diode does not charge then swap ends of the coil.  If you know which end is which (I think you said they were labelled) take the end that is the same phase as the primary that goes to the collector and connect it to the diode with the diode cathode going to the positive of the cap.  Now run the system and see which one charges to the highest voltage.  Since the current really only flows one way to start as the coil discharges there should be almost the same voltage in both caps.  Since there is less voltage drop in the circuit with the single diode it may even be higher.  Let me know what you find.  I am curious about this myself.

From you last couple of questions I think you might be confused about the difference between a diode and a bridge.  They both convert AC to DC but in a slightly different way.  A diode blocks current flow in one direction.  So the pulse from the discharge of the main coil can go to the charge battery but the charge battery cannot send any current back through the main coil.  That is why there is a diode from the collector to the charge battery.

A bridge also blocks current from the cap or battery but allows current from the coil to go to the cap or battery no matter which side of the coil is positive or negative.  Look up how a bridge rectifier works and you will see what I mean.  And then the test I proposed will also make more sense.

Later,
Carroll

[earthbound0729]

Thanks for this reply Carroll.

Why do we need a bridge on the other non-powered windings?

I have already read and checked that all these windings produce AC voltage, so bridges would be necessary.

When current flows through a diode there is a certain amount of voltage drop across the diode.  Usually that is about .5 to .7 volts. except for special diodes like shotkey diodes.  When you use a bridge the current in one direction has to go through 2 diodes to get to the cap or other load.  So a bridge causes twice the voltage drop of a single diode.

I have researched surface mount as being super fast switching with good voltage to > 100 volts and amps up to 30, while the Schottkys come in similar variety with various forward voltage drops as you noted but handling less voltage and amperage generally speaking. It appears that SMDs even have better values, definitely more difficult to work with due to their size.

I can see by merely using my 1N4001 or the 1N4007 both have a forward voltage drop of 1 volt, so I am wasting 2 volts right off the bat compared to the Schottkys or variants and with each lead putting out only 4.5 volts on the DC side  now. I can do better. With 6 filars left to use, that is 12 volts wasted currently if I used individual bridges to them all, while I am only getting 4.5 x 6= 27, compared to optimum 6.5 x 6 = 39 volts.
It would seem plausible Carroll that I could run the 6 filar through 1 bridge circuit and save all those lost volts except those sacrificial ones. And even the 1N4001 could handle that. I do have plenty of those and the 1N4007. It is worth the trial. Can't hurt. Trial one would have to be in parallel.

Trial 1 Parallel: Of course, the voltage has not increased 1 lick as expected, but the amps should have increased somewhat and when I connected the wires there was a definitely a noticeable spark.

Now Carroll, based on the data you covered in an earlier post related to the direction of travel of the Radiant pulse upon the collapse of the magnet field, should a series wound experiment be particularly profitable by causing an additive voltage effect?

From you last couple of questions I think you might be confused about the difference between a diode and a bridge.

I am definitely lacking in theory. I wasn't aware of that, I only thought the diode prevented reverse voltage from occurring through the path in which it was connected.

Thank you again for your continued help Carroll.
dave