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Q-bert controls software asjustment ?
SirPoonga:
Level42, why is the darlington in there? Don;t we need to just switch the coil on and off. Wouldn't the optisolator do that?
2600:
--- Quote from: SirPoonga on June 19, 2006, 10:16:07 am ---Level42, why is the darlington in there? Don;t we need to just switch the coil on and off. Wouldn't the optisolator do that?
--- End quote ---
I think it's because he is copying some designs and literally throwing an opto-isolator in there just in case. As it is now, I think the circuit is going to risk blowing the darlington up and doesn't have the otpo really hooked up correctly anyways. Also, the opto isn't spec'd so maybe it can't support enough current to drive the coil.
Level42, try keeping the topic to one thread and it may be easier to help.
Level42:
--- Quote from: SirPoonga on June 19, 2006, 10:16:07 am ---Level42, why is the darlington in there? Don;t we need to just switch the coil on and off. Wouldn't the optisolator do that?
--- End quote ---
No, the optoisolator will not be able to handle such high currents.
There actualy are optoisolators with darlingtons around, but none of those still have the specs of the 6N6044, else I would have gone that route.
Level42:
--- Quote from: 2600 on June 19, 2006, 11:00:30 am ---
--- Quote from: SirPoonga on June 19, 2006, 10:16:07 am ---Level42, why is the darlington in there? Don;t we need to just switch the coil on and off. Wouldn't the optisolator do that?
--- End quote ---
I think it's because he is copying some designs and literally throwing an opto-isolator in there just in case. As it is now, I think the circuit is going to risk blowing the darlington up and doesn't have the otpo really hooked up correctly anyways. Also, the opto isn't spec'd so maybe it can't support enough current to drive the coil.
Level42, try keeping the topic to one thread and it may be easier to help.
--- End quote ---
Mmmm.....the reason why the darlington is in there is that it was there in the original design by Brad (see http://members.cox.net/brado426/build.htm), which in itself is basicaly a copy of the original Q*bert's triggering circuit. You can read my reponse to SirPoonga for the reason why it is still needed in my diagram.
I've never claimed to invent something new here !!!!
I merely try to make the diagram a bit safer. The reasons why I "literally throw in" an optoisolator are already spelled out in this thread, but you don't seem to care to read it, so I'm not going to repeat them here.
So back to the facts:
Can you explain me why you think there is a risk of blowing up the darlington ?
Can you explain me why the opto isn't hooked up correctly and how should it be hooked up in your view ?
Again proof that you haven't read the full thread: The opto isn't spec'd because I don't know WHICH opto to use yet, BECAUSE I need to find one that can handle the voltage (the current is NOT the issue here, if you really understand anything about electronics, you know that the current through the base of the darlington is now limited by R2).
Any help is very much wanted and appreceated, but just posting some negative remarks without any facts WHAT is wrong in my design is not what I am calling help.
Just to be very clear: I am PROPOSING an improvement on an existing WORKING design. Build the design by Brad, and it will work. MY improved design is still theory only, not built and tested yet.
EDIT: attached the full jpg here, that may be a bit clearer than linking the image.
SirPoonga:
--- Quote from: Level42 on June 19, 2006, 01:19:16 pm ---Just to be very clear: I am PROPOSING an improvement on an existing WORKING design. Build the design by Brad, and it will work. MY improved design is still theory only, not built and tested yet.
--- End quote ---
I can follow a schematic, I can build from a schematic, I'm not good at coming up with circuit designs.
I see a couple of differences between the qmame design and yours. Like fuse on opposite side and the added cap. Why?