Hello ALL,

A fellow member of this forum, JDO300, asked me to post this for him.  He is busy working on his new sine wave generator. 

"Hi Bruce,

Here's the schematic I mentioned to you. Rather than using the 4017, this circuit uses a 74HC164 Shift register. That in combination with a NOR Gate produces the same effect as the 4017 (and the circuit could easily be modified to use the 4017 instead). But the useful thing here is that the signal source's pulse width is used to control the output pulse widths of the three channels simultaneously through the use of the three AND gates.

I didn't bother to redraw the circuit with the 4017 since I already had it in my stash so I thought I would pass it along. The signal source can be a 555 timer or any other suitable clock source." 

Any questions can be directed towards Jason.  Thank you.

Here's some info on port registers for the Arduino. Being a software dev I'm sure you will have no problems getting the Arduino to do what you like. This is just for future reference should you need the functionality;

Thanks, that looks handy.

Have you seen this example:

http://arduino.cc/en/Tutorial/Fading

You could use a single analog output to keep it on high and fade it out afterwards.

I am not looking to fade for now. Those were digital ports.

It's pretty easy to have overlapping signals. Instead of using the delay function and letting the whole microchip do nothing for a while, you check if a certain time limit has passed if not you ignore the code block and move on to the next. Here's yet another example:

http://arduino.cc/en/Tutorial/BlinkWithoutDelay

An arduino is really a must next to an oscilloscope and a singal generator in this field, it allows for fast prototyping and feedback without too much headaches and it's cheap. I know tony wanted to keep things simple, hence the simplified decade timer, but an arduino offers much more control and is very simple to adjust on the fly thus ideal for finding the right parameters.

Thanks. Yes I agree. Actually Arduino will also keep it simple.


@Nikola Tesla

Yes I did try these things a year ago and worked but used flyback diodes and thicker for primary thus blown my PSU, later PG and other instruments so I gave up at that time.

@Lindsay

1. Set the PG to 1kHz/50% and leave it as a constant reference signal, that should always work. And BTW it is not sensitive for frequency like a radio device. Think of the importance of frequency like at a switching PSU. Nothing more.

2. Make sure the IGBTs turn on properly.

3. Check the primary if it's not too thick. Mine is 0.38mm.

4. Check the left/right handed winding thing on both primaries and secondary. Perhaps it also counts. Take it as a reference:
http://www.samsonium.org/sites/default/files/P1060253.JPG
(That is equivalent with 1 primary)

5. Make sure the signal is square wave, not sine or "flatter". (it works correctly with poor squarewaves as well)

6. Remove the bulb and let it to run without load for now.

7. Make sure the gaps are correct between the turns. If they are too close you really need the juice to see something on the scope.

8. If you still have problems please don't hesitate to send photos or we can chat on Skype if you'd need further help.

UPDATE

9. Make sure the secondary is tight enough. No need to force it just make sure it's not loose. That gives much worse output.

Some simple math:
1 KHz @ 50 % driving e.g. coil that is powered by 12 V and has a resistance of 1 ohm.
- Max. current in the primary will be 12 A
- Power consumed by the primary is 12V x 12A x 0.5 = 72W

I am sure the primary will get hot with these settings.

Yes, I am aware that impedance will limit the current somewhat more, but with 36 windings it will hardly count.

Tony
Something is different in this thread!
Feels very good.

Perhaps they tried out what I said and fight with their breaths.

@ tony .. ok more work tonight when the heat dies down here.

try one primary at a time?
I only have one primary. Have i missed something there?

thanks

lindsay

@teslaalset

Thanks for the useful advices. I put more caps in parallel just to be sure. BTW I am moving on to decrease the current intake and step a bit higher with voltage as it more behaves as a voltage device rather than a current one. So I placed current limiter resistors in series with the coils.

@Lindsay

Yes we are optimising my old design to make the fact of OU less questionable, more compact and more visual  without using more TPUs. In my original design I used 2 stages of TPUs to boost up the output with LC stages and full bridge rectifiers to keep the field spinning. We are about to repeat it with a single TPU without ugly spikes, inefficient back EMFs and heating problems.

Some major modifications:

1. Gaps between secondary windings to decrease back EMF, power consumption and remove many components intended to smooth the output. With this configuration for one shot all you have to see is a big exponentially rising hump with the same falling edge and 2 or three hard to see long and almost completely flat waves as back EMF oscillation. See the 2 scope shots I sent for comparison, those were taken by the 9 turn secondary coil of mine.

2. More primary coils to distribute heat on the coils and (it is important) to fill the gaps between the pulses as it seems the winding gaps give the pulse delay not the driving frequency. We layed 2 other primary between the already wound one and shoot them in 120 degrees phase out. (I'm currently simplifying the circuitry to make it cheaper to build and more available to all testers)

The correct output signal with one primary at 50% is like this: -__-__-__-__-__.

If you increase or decrease the pulse width you'll get smaller peak, instead of shorter or longer in duration, also the gaps remain stable at any frequencies. This is why the 2 more primary.

Input signals:
---___---___---___---___
_---___---___---___---__
__---___---___---___---_

Output signal:
--------------------------

So you should get a stable HV high current DC with some insignificant waves on it's top without LC.

3. We use thinner primary wires than the original has, as it seems the device likes to spin electrons in thicker conductors in its environment. By using thinner wires we decrease the weight on the IGBTs and we can step below to low power transistors or darlington array or similar.

4. We use thicker on the secondary to get the power collected there rather than on the primary.

@wings
Thanks for the link. I tried the arduino stepper motor library last night but it doesn't really comply my demands. It has inaccurate output and needs feedback to work correctly.

Video in a few minutes with some explanation as I saw many of you had problems with understanding the concept.

(sorry for the delay there is no sound, I'm going to record it again )