Meye style gating cirucit

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A friend of mine wanted me to build a Meyer replica along the lines of his 8XA box.
I updated the gating circuit to 4000 series chips. It only requires one power input instead of two.
Two of the circuit boards should be in tomorrow to test.

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hello i sugest you this circuit witch is pulse width variable, you just need to change the capacitor value to change the frequency range with a simple switch... http://www.rmcybernetics.com/projects/DIY_Devices/homemade_pulse_controller.htm


Its very good design in my opinion, however you could consider using a voltage regulator for 12v and a mosfet driver like tc4420 to assure correct turn on and off speed of the mosfet... oh you could also use instead of this 740, the irfp360


Get also some diodes for protections and rectify the currents...


good lucky to you 

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a variable capacitor won't replicate the Meyer gating, he used divide by 10.
 
The point is is duplicate his circuit function.
 
As for the 10 volt regulator, I have found that the 555 timers last longer and are more stable at 10 volts. (especially the ones made today).
 
The opto isolator triggers the SCR in the 8XA unit quite nicely.
 
If I get the time I will capture the waveform off the scope and post it.

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Hi Argus,

Thats a good start!
Just build it and see what it will bring. Then go from there...

Steve

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Thanks Steve
Couple of pics of  the circuit working. The scope is hooked to the input side of the opto chip.
Also is a shot of most of the 8XA setup.
I am in the process of a rebuild of my WFC so I haven't hooked it up today.
I believe the original unit used a post mounted SCR. I can still get one but don't know if I will bother.

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here's a version of the 8XA Circuit that I came up with and its a bit simpler and does exactly the same.

-Tony Woodside-

(http://www.globalkast.com/images/tonywoodside/SM_8XA_Simplified.png)

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Ha, you used the famous crowbar (Ravi / Hydrocars) diode technique.
 
Nice schematic!