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Recent content by btvarner

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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Hi All, I have given up on this effort for now. Sorry if this post is not appropriate. I would like to hire another electrical engineer but only locally this time. I live in the Kansas City Metro area. I think it is best to be someone that I can physically see and that can physically handle...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Thanks FvM! This is what I have run into everywhere I turn with this issue. I have worked in my spare time for many months, on many different circuit designs, none successfully. I am just a photographer that is trying to achieve a goal. I even hired an actual electrical engineer. Paid him...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    No, the reason I know this is because once everything is disconnected, then reconnected, the circuit works as designed for the "first shot". Only after it is first triggered, does it thereafter remain on. I have a more detailed explanation of those actions in a previous post.
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Barry, it seems like this circuit is interesting also. Is part of it covered by the oscilloscope window? Thanks!
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Referencing Post #34 from FvM, 1) “Post #16”: You are absolutely correct. I took the last 2 images after removing the test bulb, but before moving the return (Black) wire to where it links to negative & completes the circuit. Sorry, but I do have this in place during testing with the flash...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Ok, I have been troubleshooting this problem from all angles. I do not have a solution, but I do have what I believe is exactly what is happening. The result is repeatable and predictable. No matter what high side load is used: **The MOC3010M output/detector (Pin 4 & Pin 6) remains closed...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Thanks Berry! I am going to answer this in a way that will likely make me look stupid, but then I guess I am. Anyway, the current/flow of amperes is measured as zero, but the voltage remains as 3.1V, the amount of battery voltage of the 2 D Cell batteries in the flash. I am tending to agree...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Hi CataM, 1) "you have always disconnected the battery from the bulb circuitry?" - In every test I try it first without disconnecting the battery. I just remove the bulb (Which breaks the circuit). When that never works, I then in each test try it my disconnecting the flash side battery (2 D...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Ok, I re-tested in the following manner: <Initial triggering: (1st shot) as always. Press camera shutter, triggering circuit closes, flash circuit closes, flash bulb ignites. As always, all good. <Ejected spent flash bulb from flash. Disconnected flash from circuit, DISCONNECTED BATTERY FROM...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Thanks for bearing with me. I will see if I have a regular opto-coupler and try that. I am not understanding how to "avoid" additional load in parallel to the flash unit? Sorry.
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Thanks for the feedback FvM! Ok, my mistake. The 33k resistor was in fact a 33 Ohm resistor.............. My bad. But, I am confused by the statement "Any load maintaining a load current above MOC3010 holding current of 100 µA keeps the latched state."? So, in fact the reason that the SCR...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    I understand that when using the test bulb and battery, the light would stay on until the battery is disconnected. That makes sense. But yes, its seems that the expectation would be that with the actual flash bulb, after that flash bulb is expended and especially after it is removed from the...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Hi Berry, you have it partially correct. Definations: "switch" as you used it to be the momentary switch or the switch that momentarily closes in the camera. "Light" as you used it to be the analog test bulb or the flash bulb in the flash unit. "Flash bulb" only stays on for milliseconds. When...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Hi FvM, yes it is a very special contest. Please follow the below links to images I have posted for clarification. Breadboard Layout Angle 1: https://brucevarner.com/picts/CurrentDesign_1.jpg Breadboard Layout Angle 2: https://brucevarner.com/picts/CurrentDesign_2.jpg Breadboard Attached for...
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    Why Does The NTE5465 SCR In My Circuit Remain Closed, Even With No Current?

    Sorry to be unclear on that. I can modify anything in the circuit except, Left: The momentary switch itself Right: The bulb or the power supply (2 D Cell Batteries)
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