I am experimenting with the circuit posted below. I am finding that the ujt/scr portion of the circuit is false triggering. This doesn't allow the capacitor to get up to the design level. I believe the kick discharge is giving a radiant e field that the ujt is sensing. Someone has most graciously suggested that I use a camera flash circuit but they all need a manual input. I cannibalized the circuitry from a dc variable voltage supply. Thankyou for any help in advance.
The scr is a 71rc10. It is actually triggered through a small air core transformer whose primary is driven by the ujt. I like it because you don't have to adjust the duty cycle. She just latches until the cap is dead. I need to follow Pesce's advice and investigate the camera flash control. Betya there is one where the shutter and flash is output as soon as the cap for the flash is up to snuff. I'm going to replace the load resisitor to the right with a neon bulb. I sure as hell am a better idea man than an engineer. :P
Naw that's cool you are experimenting, I got alot of respect for that. I'll look up and post some SCR stuff later tonite.
I am doing some experiments to investigate the concept of a kick of free energy when current is first sent down a wire.
This won't help you with your question but I am interested in the same concept and will be testing different setups as well.
The PDF results are posted on my site: http://freeenergygroup.com/
Link: http://freeenergygroup.com/wp-content/uploads/2008/05/in-search-of-the-kick.pdf
Quote from: Jon on May 10, 2008, 11:52:39 PM
I am doing some experiments to investigate the concept of a kick of free energy when current is first sent down a wire.
This won't help you with your question but I am interested in the same concept and will be testing different setups as well.
The PDF results are posted on my site: http://freeenergygroup.com/
Link: http://freeenergygroup.com/wp-content/uploads/2008/05/in-search-of-the-kick.pdf
Jon: You might want to experiment with different kinds of wire. Soft iron wire (like garden wire) might display some interesting properties. Also, I noticed that you spooled the test wire into a loop. This will introduce some inductive effects, so I'd suggest that you do your tests with straight sections of wire instead.
-zt
Quote from: sparks on May 10, 2008, 07:49:25 PM
The scr is a 71rc10. It is actually triggered through a small air core transformer whose primary is driven by the ujt. I like it because you don't have to adjust the duty cycle. She just latches until the cap is dead. I need to follow Pesce's advice and investigate the camera flash control. Betya there is one where the shutter and flash is output as soon as the cap for the flash is up to snuff. I'm going to replace the load resisitor to the right with a neon bulb. I sure as hell am a better idea man than an engineer. :P
This reminds me of a strobe light circuit. "Sidacs" can be used for the switching (is that the same as a SCR?). See:
http://members.misty.com/don/kmaxhack.html
Cheers.
-zt
Hmm yesterday i was thinking Sparks should start doing talk shows and the next morning he is experimenting... :)
You can also look at CDI systems.
CDI stands for capacitor discharge ignition which is used in combustion engines.
Normally the capacitor discharges fully into the bobbin ignition coil.
However you can Mod the circuit so it imediatly cuts off the discharge as soon as it starts..
With extremly short high voltage pulses as a result.
There are some simple circuits that use triacs and a handfull of parts.
I did have a image somewhere but i am unable to locate it at this moment.
M.
Yes sir Marco. I can go down to the junkyard and get an old gm ignition module. They were triggered by an inductive pickup which I can strategically place so that it encounters the mag field shift created by the bifilar steel/copper antennae/coil. But instead of outputing to a transformer it dumps the capacitor into the kick antennae circuit. This would send the unit into runaway though unless I deadvance the timing. :o hmmmmmmmmmm
The strobe light circuit is a great idea. It is what Pesce suggested. I'm beginning to feel that instead of hopping right in and trying to create a feedback loop I would be better off just driving this experimental circuit with an outside power scource. I could then just monitor the wattage of the input/output to demonstrate the gain.
Edit again :P
For some reason the flyback transformer inside old computer monitors or tv's popped into my noggin.
It's all right there. The horizontal output transistor pulsing it at whatever freq and low voltage low amps and high voltage same frequency same amps output. Packaged Tesla coil ready to go. :o How many lamps do I need to put in series to voltage divide 27kv. hmmmmmmmm calculator 225 at 120volts drop each bulb. This should put the mess sm made to shame.
Okay, I've never actually used a SCR so I had to go look it up. I'll post what I've figured out...
(https://overunityarchives.com/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F9%2F93%2FThyristor_circuit_symbol.svg%2F120px-Thyristor_circuit_symbol.svg.png&hash=0dc5a9a6c05ea89c57d931f57ca4d59ef7845bc0)
An SCR is a 'thyristor' , which is like a transistor but it has four layers of silicon instead of three (PNPN). Now bascially, the idea in an SCR is that when the gate receives a current pulse, it lets current flow across the anode/cathode junction... until the voltage reverses! So basically it's like a transistor with a latch. Here is a good diagram:
(https://overunityarchives.com/proxy.php?request=http%3A%2F%2Fwww.onsemi.com%2Fsite%2Fimages%2FprotectionThyristorOp_fig1.gif&hash=3fb02a0704a05d173f1c011b29ab3812c7bd3f34)
So again, the operation is as follows. A pulse hits the gate. This lets current flow along the anode/cathode junction, even if you REMOVE the current at the gate. It's like opening a waterfall, it just keeps flowing. There is only one way to stop the current now, and that is if
1) The anode/cathode current is removed by shutting off the source in the circuit.
2) The current flowing across the anode/cathode drops below IL, which is the 'latching current'.
Let me post from the wikipedia page on thyristor...
Quotea conventional thyristor, once it has been switched on by the gate terminal, the device remains latched in the on-state (i.e. does not need a continuous supply of gate current to conduct), providing the anode current has exceeded the latching current (IL). As long as the anode remains positively biased, it cannot be switched off until the anode current falls below the holding current (IH).
V - I Characteristics
V - I Characteristics
A thyristor can be switched off if the external circuit causes the anode to become negatively biased. In some applications this is done by switching a second thyristor to discharge a capacitor into the cathode of the first thyristor. This method is called forced commutation.
Okay so that's the basics. The SCR is like a transistor with a latch. One thing to keep in mind is that SCRs can only really switch at slow speeds, so anything above about 100hz might be an issue depending on what kind of SCR you are using. I couldn't find a PDF datasheet on your SCR, so for reference I found a regular looking SCR. Here is the PDF datasheet.
http://www.datasheetcatalog.com/datasheets_pdf/B/T/1/6/BT169.shtml
Notice the latching current is 2-6mA.
As for your problem, your best bet is to test the SCR using a simple circuit to make sure there is not a problem with your SCR . According to the information I found,
An SCR or triac operates in one of two
states: it is either on or off. In the off
state, a properly operating SCR or triac
blocks the flow of current through it. In the
on state, a good SCR allows current to
flow in one direction only. A good triac
allows current to flow in both directions
when it is turned on.
Common failures in SCRs and triacs are:
1. No turn-on
2. Leakage or direct short
3. Leakage at higher working voltages
4. triac only: Short in one direction.
Learn How SCRs and Triacs Fail and How You Can Test Them with your Z Meter
http://www.sencore.com/custsup/pdf/TT125.pdf