The OTG Pulse Generator Paper

[smw1998a]

Hello All,
In the following thread The Bedini 10 coiler. Questions were raised regarding the front to back efficiency of the 10 coiler kit. A flame war ensued. Eventually, order was brought back to the thread and I stated that I would post a circuit that would increase the front to back efficiency of a standard rotor based SG/SSG by 20%, regardless of it's COP level.

Not to cause any more distractions to a thread as important as the construction and reporting of the new 10 coiler kits, I thought it would be better to create a separate thread regarding the paper I put forward, should anyone wish to discuss it further.

Regards Lee.

OTG Group Pulse Generator Paper

[ewizard]

I guess I missed the flame war or even any discussion as I think I only saw that thread when it first was posted. So without knowing anything about that I'll just say the paper you have written up is very nicely done. I haven't gone over it in detail but it's well presented and I will read it soon as I believe you have some good info in there. I appreciate that you have taken the time to document everything so clearly.

[Sephiroth]

Great presentation

[smw1998a]

Pulse Gen Demo

Hello All,
@ewizard/sephroth. Thanks for you kind comments.

I intended to make a video to go with the paper

OTG Group Pulse Generator Paper

I just haven't had the time. There is an old video on my You Tube channel showing the pulse generator circuit in action.

Pulse Generator Demo

When I first posted this video, it will have appeared to lack context, unless you were a member of the OTG . The paper will put this video into context. I don't demonstrate frequency control in this video but full control over your SSG's frequency is very easy with the pulse generator circuit while current draw is controlled with base resistance, as seen in the demonstration. It is important to realise that the solid state I refer to is not the same as self oscillation or 555 driven transistors. This is an SSG circuit running without the trigger signal from the rotor.

Regards Lee.

[smw1998a]

New Youtube video

Hello All,
As promised and far later than I intended.

YouTube - OTG Pulse Generator.avi

Regards Lee..

[carmine]

ty

Thank you .. nicely done

[theremart]

Sourcing parts...

0.25W Carbon Film Resistors 4K7, 10K x2


I am sorry, I am a block head when it comes to ordering electronic parts.

Is this a 4.7K Resistor? and a 10K ?

Thanks!

[ashtweth]

You Rawk Lee thanks a lot man

[smw1998a]

0.25W Carbon Film Resistors 4K7, 10K x2


I am sorry, I am a block head when it comes to ordering electronic parts.

Is this a 4.7K Resistor? and a 10K ?

Thanks!

Hi Mart,
Yes that is right. 4K7 = 4.7K = 4700 Ohms and two 10K resistors. It does get confusing

@Ash. Thank you..

Regards Lee.

[theremart]

Thanks Lee

Parts are now ordered, hope to have them in the next week or two.

I have a dual transister bedeni that I am looking forward to testing this on.

Mart

[smw1998a]

Parts are now ordered, hope to have them in the next week or two.

I have a dual transister bedeni that I am looking forward to testing this on.

Mart

That's great news Mart. Please let me know how you get on.

Regards Lee.

[theremart]

Circuit completed.

Still working to learn the circuit.

It sure squares up the H wave. I have found even when it is off, the H wave squares up nicely when attached.

Mart

[smw1998a]

Still working to learn the circuit.

It sure squares up the H wave. I have found even when it is off, the H wave squares up nicely when attached.

Mart

Hi Mart,
Good news that you completed the circuit. The waveform is identical to the rotor based SSG without the induced voltage 'hump' of the rotor magnet as it approaches TDC or registration with the pole piece. However, I'm a little confused over your statement. If the pulse generator is off then the trigger circuit should not activate. Are you using the pulse generator on a SSG circuit?

Regards Lee..

[theremart]

RE: my setup.

Hi Mart,
Good news that you completed the circuit. The waveform is identical to the rotor based SSG without the induced voltage 'hump' of the rotor magnet as it approaches TDC or registration with the pole piece. However, I'm a little confused over your statement. If the pulse generator is off then the trigger circuit should not activate. Are you using the pulse generator on a SSG circuit?

Regards Lee..

So far I have used a Bedini fan with the setup with an SSG setup for starters. I am not sure everything is ok, since the first voltage i hooked up to the setup was 12 V. It did not like that, I smoked at least 2 555 chips with that setup. So I have moved to 4 AA batteries and it seems to be stable with that.

I think the next thing I should do is give you a scope shot of the wave with nothing hooked up.

I watched your video again today and I see that you calibrate with the frequency setting on your volt meter. I don't have one of those meters, so I guess I will start with basics and upload a scope shot of the output.

Let me upload the scope shot, of just the frequency generator with nothing attached and see if what I have is right, it looks like a square wave if I remember right.

Mart

[smw1998a]

So far I have used a Bedini fan with the setup with an SSG setup for starters. I am not sure everything is ok, since the first voltage i hooked up to the setup was 12 V. It did not like that, I smoked at least 2 555 chips with that setup. So I have moved to 4 AA batteries and it seems to be stable with that.

I think the next thing I should do is give you a scope shot of the wave with nothing hooked up.

I watched your video again today and I see that you calibrate with the frequency setting on your volt meter. I don't have one of those meters, so I guess I will start with basics and upload a scope shot of the output.

Let me upload the scope shot, of just the frequency generator with nothing attached and see if what I have is right, it looks like a square wave if I remember right.

Mart

Hi Mart,
The only time I have had reported failures with this circuit is when the SSG is run without a charge battery, the induced negative voltage in the trigger winding causes pin 3 of the monostable to go below zero volts destroying that chip. You are correct, the astable should show a square wave but on the high to low transition the mono stable outputs a 5 microsecond pulse directly to the base of the transistor via a 1N4007 diode connected to pin 3 (green wire in the schematic). The scope waveform at maximum frequency should show this very short pulse if you connect your probe ground to circuit ground and your probe to the green wire. The circuit should consume very little power as the short pulse to the base of the transistor carries very little current and as a result the supply voltage shoulde't affect the circuit to any noticable degree. I have had no reports of anybody applying this circuit to the fan conversion but as long as it is an SSG circuit I shouldn't think there will be any problems.

Regards Lee..

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