Can you post details on t he SCR?

This page is okay too
http://en.wikipedia.org/wiki/Silicon-controlled_rectifier

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

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

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.

Okay, I've never actually used a SCR so I had to go look it up.  I'll post what I've figured out...
(http://upload.wikimedia.org/wikipedia/commons/thumb/9/93/Thyristor_circuit_symbol.svg/120px-Thyristor_circuit_symbol.svg.png)

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:

(http://www.onsemi.com/site/images/protectionThyristorOp_fig1.gif)


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...

a 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