This is it !

[Farmhand]

If somebody could work out this equasion we would know how much power is needed to drive each mosfet gate properly. The Qg for an IRF540Z is 42 nC typical and 63 nC max. No idea what the rest means. The formula comes from the drive current and power requirements.

P = C × V2 × f = Qg × V × f

Cheers

[gmeast]

driver

From the "input stage" section



That's why it's called a low side driver. 3.3 volts on the input side will drive the output MOSFET all the way to Vdd. But, the input also supports full voltage signals, so no need to worry about frying it.

The logic gates aren't going to provide much current and the output side of this thing supports up to 9 amps, so I think frying it would actually be an amazing accomplishment.

Hi 7imix,

Thanks! Ha ha! ... but you've never seen me in action. In my immediate circle, I'm known for making the 'unlikely' happen on a regular basis ... that means good AND bad!

And Farmhand, now that you are aware of THAT, would I still be welcomed in Australia?

Thanks again 7imix. Now I will take them out of the box.

And @ both of you and anyone else following, I have begun on my primaries. I did the layout on the yellow tape for the 90deg worth of tuns on 120deg centers, staggered around the secondary exits by + & - 15deg ... as prescribed in the Toroid Winding Guide and depicted on the color-coded winding protractor.

I used the radius-long-chord piece of wire (1/2 diameter) to layout the 120deg steps then spaced the 90deg sections using another chord of 45deg which calculated to 0.76(something) Radius. That's really close to 0.75R, so I cut off 25% of my R (folded the wire) and used that to step off the rest of the layout. I'll wind a little before and beyond those angular thresholds. The first wrap will say much about what follows (does I gots enough wire for the full 90 deg and all).

Pictures here:
http://02d1852.netsolhost.com/radian...es/layout0.JPG
http://02d1852.netsolhost.com/radian...es/layout1.JPG
http://02d1852.netsolhost.com/radian...es/layout2.JPG
http://02d1852.netsolhost.com/radian...es/layout3.JPG
http://02d1852.netsolhost.com/radian...out_finish.JPG


Later

[Farmhand]

Hey Greg i'm thinking we might want to go with 50 winds to make the coil leads longer. Mine are too short really, I think.

And Farmhand, now that you are aware of THAT, would I still be welcomed in Australia?

I'm not sure what you mean by "THAT", but you look like a hard worker and hard workers are always welcome.

Haha 7imix beat my post by 2 minutes. I'll have to learn how to type with a few more fingers.

Don't forget you'll have to pulse those 3-2-1- as they are marked CCW .

Hey I was thinking if there is a pole reversal of the planet we might have to unwind and rewind our toroids, cause i'll be up there and you'll be down here.
Or we could send them to each other !

[gmeast]

Hey Greg i'm thinking we might want to go with 50 winds to make the coil leads longer. Mine are too short really, I think.


.................................................. .................................................
.................................................. ................................................
Don't forget you'll have to pulse those 3-2-1- as they are marked CCW .

Hey I was thinking if there is a pole reversal of the planet we might have to unwind and rewind our toroids, cause i'll be up there and you'll be down here.
Or we could send them to each other !

Hi Farmhnad,

I think we should just move to the equator, Either it won't matter there, or they won't work at all.

50 turns is a good number for me too. It will give me good lead lengths also. I'm not sure I like wrapping over that tape. Because the wire is fairly small, even the wrinkles in the tape squirt the wire off position. I think it would have wrapped much nicer right over the secondary and wax. I worked very hard to make that smooth and flat only to cover it in wrinkles ... stupid!

Got P1 done (except for evening out the spacing on the periphery).

Some pics here:

http://02d1852.netsolhost.com/radian...maries/P-1.JPG
http://02d1852.netsolhost.com/radian...aries/P-1a.JPG
http://02d1852.netsolhost.com/radian...aries/P-1b.JPG

Later

[gmeast]

finishing a primary

Hi Farmhand and 7Imix,

Here's some toroid-progress. I wound all three primaries on the toroid and taped the ends to secure it. I decided to completely finish each primary before staring the next ... meaning straightening, waxing, vinyl taping and transformer taping.

In the pictures it looks like some of the spacings were off ... and they were. With the wax still a little soft, I was able to push things into place and they stayed put instead of springing back.

The pics are here:
http://02d1852.netsolhost.com/radian.../begin_wax.JPG
http://02d1852.netsolhost.com/radian...irdle1_off.JPG
http://02d1852.netsolhost.com/radian...irdle2_off.JPG
http://02d1852.netsolhost.com/radian...rdle2_off1.JPG
http://02d1852.netsolhost.com/radian...es/end_wax.JPG
http://02d1852.netsolhost.com/radian...inyl_tape1.JPG
http://02d1852.netsolhost.com/radian...nyl_tape1a.JPG
http://02d1852.netsolhost.com/radian...ormer_tape.JPG

AGAIN ... who would ever use 2" wide tape on these things? It's hard enough to do a good job with 1" wide tape!

Later

[Farmhand]

Looks Good

Hey Greg, did you go with 50 turns ? How come you used the black tape ?

I got no reply from loadstone pacific. I'm going to town tomorrow so i'll try to get some then. I'll make a list of some parts to get and order too.

Might get to wax and space my primaries after i have a play tonight. I'll need the Vegemite.

Have you guys tried vegemite. It's good tucker.

Cheers

[gmeast]

black tape

Hey Greg, did you go with 50 turns ? How come you used the black tape ?

I got no reply from loadstone pacific. I'm going to town tomorrow so i'll try to get some then. I'll make a list of some parts to get and order too.

Might get to wax and space my primaries after i have a play tonight. I'll need the Vegemite.

Have you guys tried vegemite. It's good tucker.

Cheers

Hi Farmhand,

I have 50 turns on the primary with nothing to spare. My leads are only about 14 inches long. 50 Turns takes me to about 100degrees of turns.

The Toroid Winding Guide says on page 7, end of first 1/3 page just before the Loadstonepacific link:

"Tape the entire core well with tightly-stretched PVC electrical tape after winding, to ensure that the primary windings do not move and then add an outer layer of winding tape."

Since I'm fully completing each primary as I go I'm winding both tapes at that time.

The guide is obviously an assembly of several documents ... it's very poorly edited. I'm sure they meant to say to tape with the PVC tape after WAXING ... which would make more sense.

If I were building a cell, according to the formulas on that same page, I should only have 39 turns. That would put me at nearly a perfect 90degrees of turns (single layer).
But we're NOT doing cells.

The Toroid winding PDF is here:
http://02d1852.netsolhost.com/radian...oidWinding.pdf

Later

[gmeast]

quoting self ... what's up with 90 degrees?

Hi Farmhand,

I have 50 turns on the primary with nothing to spare. My leads are only about 14 inches long. 50 Turns takes me to about 100degrees of turns.
.................................................. .................................................. .................................................. .................................................. .......
If I were building a cell, according to the formulas on that same page, I should only have 39 turns. That would put me at nearly a perfect 90degrees of turns (single layer).
But we're NOT doing cells.
.................................................. .................................................. .......
Later

@ Farmhand,

Now, here's where we need some input from someone like Bob Boyce since he know what we're trying to accomplish.

In the guide, it says that you may need more than one layer (primaries). This, I assume, is based on the number of turns you ended up with on your secondary AND by applying the 'turns ratio' formulas.

Now I'm taking this to mean, also, that you may need more than one layer:

'... in order to meet the formulas' results' AND stay confined to within 90degrees angular on the toroid. I'm sure Bob didn't specify the '90deg worth of turns' figure 'cause it's a nice number ... it more likely has allot to do with phase angle, non-resonance and the generation of non Hertzian (waves) values.

If that's the case, then I need to unwrap as many turns as it takes to get me back to 90deg ... that would be about 5 turns off of each end of the winding ... then I would have LONG leads for sure.

I can't put my finger on it, but 90deg long coils centered on 120deg spacing must have some significance ... or not. Dunno.

Later

[7imix]

I got my clock chips, MOSFET drivers and MOSFETs today. Wow, that ltc6900 is insanely tiny. I'm going to need to get a board with the right spacing to install it on.

Greg, I worked on my op amp impulser build yesterday. I Had been experimenting on it so I went back to your original drawing and reassembled it so it matched what you posted at the end of last year. One thing about my build that I am having a problem with (and was having a problem with before as well) is dc bias. Even with the fourth dc offset op amp in the circuit, I always have a dc bias of about 800mV.

Oh, that gives me an idea... Maybe I just put an inverter or two after the output to lock it to rail to rail.

[rave154]

ya...i remember ordering two of those ltc6900, eagerly itching to get my hands on them so i could rig up a nice FG.....then i opened the anti-static bag..at first i thought the bag was empty lol

[7imix]

Ok I added two inverters as a buffer and hooked up the MOSFET driver. Running it on 6 volts, I get some beautiful spikes out of the MOSFET driver. I bet it would be even nicer with a faster buffer and higher slew rate op amps.

YouTube - Op amp pwm + inverter + mosfet driver = 3% pulse width

Rave154, how can I hook up something that small to a breadboard? There has to some trick to interfacing those pins without soldering...?

[Farmhand]

@ Farmhand,

Now, here's where we need some input from someone like Bob Boyce since he know what we're trying to accomplish.

In the guide, it says that you may need more than one layer (primaries). This, I assume, is based on the number of turns you ended up with on your secondary AND by applying the 'turns ratio' formulas.

Now I'm taking this to mean, also, that you may need more than one layer:

'... in order to meet the formulas' results' AND stay confined to within 90degrees angular on the toroid. I'm sure Bob didn't specify the '90deg worth of turns' figure 'cause it's a nice number ... it more likely has allot to do with phase angle, non-resonance and the generation of non Hertzian (waves) values.

If that's the case, then I need to unwrap as many turns as it takes to get me back to 90deg ... that would be about 5 turns off of each end of the winding ... then I would have LONG leads for sure.

I can't put my finger on it, but 90deg long coils centered on 120deg spacing must have some significance ... or not. Dunno.

Later

Hi Greg, I just woke up from a 12 hour sleep so I hope this makes sense. This is how i'm seeing it, if the H20 cell required 56 turns I would wind 2 layers of 28 turns, is it ok to do like 48 turns with 8 turns on top, I wouldn't do that, I would do two even layers and that wouldn't be 90* either it would be a fair bit less. The only way to be sure would be to look at Waky's toroid untaped. There is no way to know how many turns he has untaped but you can see the imprint of the space between his primaries.

I think the 120 centers and some space between is important, if you are concerned about it at this point, you might as well wait and see it will be just as easy to unwind some later. Unless you haven't finished taping yet.

Hmmm hard to say.

Cheers

[gmeast]

parts

I got my clock chips, MOSFET drivers and MOSFETs today. Wow, that ltc6900 is insanely tiny. I'm going to need to get a board with the right spacing to install it on.

Greg, I worked on my op amp impulser build yesterday. I Had been experimenting on it so I went back to your original drawing and reassembled it so it matched what you posted at the end of last year. One thing about my build that I am having a problem with (and was having a problem with before as well) is dc bias. Even with the fourth dc offset op amp in the circuit, I always have a dc bias of about 800mV.

Oh, that gives me an idea... Maybe I just put an inverter or two after the output to lock it to rail to rail.

Hi 7imix,

Some op-amps will go to the - rail, some to the + rail and some to both rails. Allot of comparators will go 'rail to rail' ... good search parameter. My op-amp pwm has .8v too. That's the one on the perf-board. But the one on the solderless board goes down to 0.08V ... don't know why ... I'll send a picture:
http://02d1852.netsolhost.com/radian...ll-Out_PWM.JPG

Maybe if you used a real comparator for the 'comparator stage' ... like the 339 comparator it's pretty good.

Oh boy someone just gave me my mail. I has my DigiKey order with my LTC6900's and my SN74LS85's!!! I'm going to post two pictures when I'm done ... one with the 5-chip generic comparator and one with the 85.

What I've done with SOT packages is mount them on a piece of perf-board and and solder legs to it that way so I have a .300 spacing X .100 pitch ... it's never failed me. Then I can find it when I drop it.

Later

[Farmhand]

Hey Greg, Call me crazy but did you actually measure your core ? It looks kinda different, did it come wrapped like mine did ? If I went to 45 turns mine would be very close to 90*. Is there a chance your's is a different diameter or height or something.

I'm easy going about this because I won't be cutting the wire's, well not for a long while yet. So i'm happy to start with 90* of turns. It might be the more fail-safe approach. I think it's important to put aside any of my own pre-conceived idea's at this point and stick with the program. Even though sticking with the program is not usually in my nature.

I'm already getting funny idea's about filling the spaces between the primaries with one coil wound like three series connected coils, like three coils wound in series without cutting the wire. It could be used like another secondary maybe or pulsed aswell or instead of the other pimaries. But thats another one for later.

I can't help it I have an active imagination. I haven't spaced my primaries or anything yet. My neck is playing up again. Dammit. It make's me like chronic fatigued. I may have to dalay my trip to town a few days.

Cheers

[Farmhand]

Hey Guys I found a better place to buy electronic componants online, I think.
Not sure if they will have everything i need but maybe most.

Components Circuits - 74LS Series&category_title=74LS Series&main_menu=IC&sub_menu=IC74LS

I can get the 74LS85's for 42 cents each. Compared to $1.95 ech from the electronics store in town.

And IRF540's for 63 cents each. In town they want $6.95 each.

I think i will have to have a talk to those guys if I ever go back there.

Could those price's be for real, I will find out.

I have an idea for another practical use for this self charger effect. It's to do with self charging too.

Cheers