The Underground Lab

[darkwizard]

very good job

[ren]

Cool Seph.

Lookin forward to seeing that nsns!

If you have an all north rotor on all ready it's perfect to try just the half circuit on. I'd recommend building a half circuit before the full, just to get a feel for it.

Yes, it doesn't make alot of sense, you'd think that it's top pnp wouldn't make much difference. But, as you know, there is always more than meets the eye with these designs That top pnp you'd think wouldn't do much, but it changes the whole process IMO.

Grab yourself some mpsa06 x 5 (spares) and a couple 2n3055s and MJ2955s, just make sure they are complimentary ie same packaging.

When your ready to go hit me up, if you need a hand. You don't really need a charging battery to start with, that is, it shouldn't pop your circuit without one.

Regards

[tjnlsn255]

So is that why the 1/2 circuit might be used on a system with a seperate generator coil to feed back to the source battery?

Hopes and Dreams.....

Tj

[Sephiroth]

Cool Seph.

Lookin forward to seeing that nsns!

If you have an all north rotor on all ready it's perfect to try just the half circuit on. I'd recommend building a half circuit before the full, just to get a feel for it.

Yes, it doesn't make alot of sense, you'd think that it's top pnp wouldn't make much difference. But, as you know, there is always more than meets the eye with these designs That top pnp you'd think wouldn't do much, but it changes the whole process IMO.

Grab yourself some mpsa06 x 5 (spares) and a couple 2n3055s and MJ2955s, just make sure they are complimentary ie same packaging.

When your ready to go hit me up, if you need a hand. You don't really need a charging battery to start with, that is, it shouldn't pop your circuit without one.

Regards

Hi Ren,

I have a surplus of MJL21194 transistors so have ordered half a dozen MJL21193 to go with them. Would another MJL21194 be ok to use in place of the SPSA06?

[ren]

Hmm.not ideal I'd think, but would probably still work. Could use 2n3055 too I guess. Any small signal transistor (npn) should be ok. 2n3440 mje340 mj3055

If you pm me your postal details I'll send you a string of mps if you like, they are cheap as chips, actually cheaper, considering the price of chips these days.

Give it a go with what you got and we can go from there.

Regards

[Sephiroth]

Cheers Ren I might take you up on that. The PNP transistors arrived today and I have a few other little transistors I've pulled out of an amplifier that I'll give a go... if they fail I'll let you know

Many thanks

EDIT : Forgot to mention I finally got the main portion of the website back online last night
The Underground Lab : Studying Bedini Technology

[Sephiroth]

THANKS REN!



Full Sequential Bipolar Circuit





Haven't had time to do test yet but will fiddle with the tuning and get some performance measurements this weekend.

EDIT : It will get up to 5600rpm for 12watts, which is 1000rpm faster than the ssg or half bipolar circuit for the same input power but will have to see how well it performs under load.

[ren]

HEY HEY HEY!

Looks awesome dude! Did you use MJE340 as your signal transistor?

Now as you already noted, it functions differently to the SG, here are some things to consider.

1. You can fill a cap off the bridge rectifier, Which should (in my case anyway) usually reach double the voltage of the input. You might get different results, but thats what I found. That cap can run a CEMF load, or you could use it to charge another battery (not as well as the SG) OR you can set it to fill up and be pulsed back to the primary. This method seems to be what the bipolar circuit is all about. You can short the bridge rectifier straight back to the input permanently, for a small decrease in input power, but it seems to slow the top speed a little. Thus the best method IMO is to dump the cap or connect the bridge when the motor circuit is OFF. "S1" in all of Johns diagrams Now doing this at 5krpm plus could be a little difficult You may be able to configure a timing belt or such to flip a double pole relay ever so often or something. Use a 20000uf+ cap over the input terminals as well.

2. Amp draw is not necessarily reliable on this thing. I have seen my motor draw significant amperage (1 amp plus) for some time, only to have to battery come back to within 0.04v of the starting resting voltage, which it should not have done. There would appear to be sweet points still in the tuning, but take your time. You may see the voltage decreasing under load, but dont terminate your test on that alone. Make sure you check to see what the voltage bounces back to after the run. If you tweak the tuning right, it wont draw alot more under load, but if not, loading the shaft does increase the input current. But once again, read above. All is not what it seems. Especially if you are returning power to the input via full wave bridge.

3. Hall sensors would allow you to get even faster for less input IMO, though a timing disc would be another accessory needed. Ive also seen reed switches used to trigger the base of the sig tranny too.

Its a bit of a dog to tune with the pots on the full bipolar. If possible you could get a dual pot to tune both banks at the same time, rather than adjusting each bank separately like I did in my RPM TEST video. Also, you can just put high resistance on the triggers and use a DPDT switch to short a low resistor on the trigger to start it. Once running you just switch to high resistance.

Also, consider a little bit of flywheel added to the shaft.

Check this video out I just posted. YouTube - Westons Magneto

I cant turn the shaft on this one by hand without the flywheel connected. The magnetic lock is too strong. The thing runs fine with that big flywheel on it. 3000 turn generator coil fills up the caps on top. Flywheel seems to make all the difference.

Great work again Seph. Glad you are havin fun. Looking forward to seeing a video soon.


Regards

[Mark]

Nice looking motor Ren!

Lol, I was trying to slow motion thru the video so I could study it better but its not in high def. Looks like 6 trans and 4 motor coils, cap discharge with comutator set up. Sweet! I liked to here more about your set up.

Mark

[ren]

Hi Mark,

Maybe in another thread

I just wanted to show how some added flywheel helped.

Regards

[Sephiroth]

Looks awesome dude! Did you use MJE340 as your signal transistor?

I've no idea what those transistors are. I pulled them out of a pc fan. I tried looking up a datasheet for them but can't find one. All I know is that the a relatively sensitive compared to the mjls and they are npns...

Now as you already noted, it functions differently to the SG, here are some things to consider.

1. You can fill a cap off the bridge rectifier, Which should (in my case anyway) usually reach double the voltage of the input. You might get different results, but thats what I found. That cap can run a CEMF load, or you could use it to charge another battery (not as well as the SG) OR you can set it to fill up and be pulsed back to the primary. This method seems to be what the bipolar circuit is all about. You can short the bridge rectifier straight back to the input permanently, for a small decrease in input power, but it seems to slow the top speed a little. Thus the best method IMO is to dump the cap or connect the bridge when the motor circuit is OFF. "S1" in all of Johns diagrams Now doing this at 5krpm plus could be a little difficult You may be able to configure a timing belt or such to flip a double pole relay ever so often or something. Use a 20000uf+ cap over the input terminals as well.

Unfortunately I am limited on space with the MG2... I'm learning what I can from it before I start building the MG3 which I think this circuit will be better suited for. The MG3 will have more space to add a more complex circuit and I think your right that a timing wheel is going to be necessary...

3. Hall sensors would allow you to get even faster for less input IMO, though a timing disc would be another accessory needed. Ive also seen reed switches used to trigger the base of the sig tranny too.

Will give hall sensors a go

Its a bit of a dog to tune with the pots on the full bipolar. If possible you could get a dual pot to tune both banks at the same time, rather than adjusting each bank separately like I did in my RPM TEST video. Also, you can just put high resistance on the triggers and use a DPDT switch to short a low resistor on the trigger to start it. Once running you just switch to high resistance.

Great minds think alike I noticed during the first tests that the circuit performed completely differently when the trigger resistance was identical on both sides regardless of what that resistance was... obviously due to the self resonance, so I am using a dual pot

Also, consider a little bit of flywheel added to the shaft.

Check this video out I just posted. YouTube - Westons Magneto

I cant turn the shaft on this one by hand without the flywheel connected. The magnetic lock is too strong. The thing runs fine with that big flywheel on it. 3000 turn generator coil fills up the caps on top. Flywheel seems to make all the difference.

WOW!!! Where did that come from!?! You have certainly been keeping busy!

Thanks again Ren... couldn't have built it without your guidance.

[Sephiroth]

Ok, a few things that seem pretty certain about the full bipolar circuit:

1. Once the circuit has been activated it will always be in the "on" state. Either one half will be on or the other will be on because when one half turns off, the flyback current flows through the other half's trigger winding in a direction that activates the other half of the circuit. This is actually really annoying for several reasons, and has put me off using trigger windings with the full bipolar.

2. Increasing or decreasing the resistance on the trigger winding has little effect on total amp draw, though increasing resistance does increase the number of pulses per magnet pass and lowers the mechanical output (even though input power is the same). I believe this is because of the first point I made since it means the other half of the circuit will be activating out of phase.

3. Increasing and decreasing the resistance on the other pot coming from the PNP base to the signal transistor does increase and decrease amp draw but this seems undesirable. The reason it effects amp draw is because when the resistance goes over a certain point, then the current flowing through the NPN and PNP base isn't high enough to reach saturation so it turns the NPN and PNP into variable resistors that don't turn fully on and so they dissipated energy and lower the voltage across the coil. To tune this pot I started with a very low base resistor (100ohm) and then increased the resistance on the pot until I notice the pulse duration decreasing (this indicates that the voltage across the coil is lowering).

According to the datasheet, the minimum hfe of the MJL21194 is 25. This motor wants to run on about 1 amp at full speed so the required base current should be about 40ma. On paper the resistance I would require between the PNP base and the signal transistor would be about 250ohms (at 12v)... which is similar to what I am seeing when tuning the circuit.

What are your thoughts, Ren? Does this seem correct so far?

[citfta]

bipolar circuit

Ok, a few things that seem pretty certain about the full bipolar circuit:

1. Once the circuit has been activated it will always be in the "on" state. Either one half will be on or the other will be on because when one half turns off, the flyback current flows through the other half's trigger winding in a direction that activates the other half of the circuit. This is actually really annoying for several reasons, and has put me off using trigger windings with the full bipolar.

Hi Seph,

I know you directed your post to Ren, but I hope you don't mind if I make a comment or two. I came to exactly the same conclusions you did about the bipolar circuit and trigger windings. This was the reason I decided to try optical switching using some old CD discs and a couple of opto switches I got off Ebay. By making the window wider or more narrow I could control the on time and thus current through the motor very easily. It was also very easy to adjust the timing to right where I wanted it by watching the signal to the coil on my scope. I was also able to make the motor operate very efficiently by using a narrow window because I could keep my power transistors fully on or off as I wanted. If I want a lot of speed and torque I just use a wider window for the opto switch. Sorry for butting in but I thought these ideas might be some help to you.

Carroll

P.S. I didn't go with hall-effect pickup because I was afraid the strong fields around my neo magnets would just cause more problems.

[Sephiroth]

Hi Seph,

I know you directed your post to Ren, but I hope you don't mind if I make a comment or two. I came to exactly the same conclusions you did about the bipolar circuit and trigger windings. This was the reason I decided to try optical switching using some old CD discs and a couple of opto switches I got off Ebay. By making the window wider or more narrow I could control the on time and thus current through the motor very easily. It was also very easy to adjust the timing to right where I wanted it by watching the signal to the coil on my scope. I was also able to make the motor operate very efficiently by using a narrow window because I could keep my power transistors fully on or off as I wanted. If I want a lot of speed and torque I just use a wider window for the opto switch. Sorry for butting in but I thought these ideas might be some help to you.

Carroll

P.S. I didn't go with hall-effect pickup because I was afraid the strong fields around my neo magnets would just cause more problems.

You're not butting in at all All feedback is appreciated!

I haven't used halls before so I'm happy to consider other switching methods Are there any advantages to using halls over optical switching? Can the pulse width be easily tuned using halls?

[Sephiroth]

I've just had a better idea I've got six separate coils on this thing. I could always disconnect the power winding from the coil with the triggers and then it won't self oscillate (as long as the other coils around it don't trigger it) and I'll be able to adjust the pulse width as well