The circuit only requires one relay (or MOSFET) and 16 diodes.I assumed that you need a diode on each of the 15 wrong answers otherwise there will be issues as you multiplex the other 15 relays. Let me think about it for a minute.
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The circuit only requires one relay (or MOSFET) and 16 diodes.I assumed that you need a diode on each of the 15 wrong answers otherwise there will be issues as you multiplex the other 15 relays. Let me think about it for a minute.
Yup you are right, makes sense now.You only posted one way.
But you need one diode on each line to isolate the lines.
I just noticed you reversed the Answer and the Select question probes.Thanks a ton guys! My board will have 16 questions and 16 answers so I modified the schematic a little to reflect that. My last question would be if I can get away with one single diode on the "answer" side rather than 16 individual diodes? I am attaching both ways so you can see what I am asking.
Sorry, I will fix that. I did that because that's the way the physical board will be constructed. The questions are on the left and the answers are on the right. It was just a visual thing. I can make the leads go where they need from the rear.I just noticed you reversed the Answer and the Select question probes.
Why?
If you do that, then the Red LED will come on as soon as you select a question.
With my original way, the Red LED only comes on for an incorrect answer. No light comes on when you select the question.
I thought you were using 5V for power.Would someone mind suggesting a part number for the relay mentioned in the schematic? I assume thats a normaly closed relay with a coil voltage of 12vdc +/- and secondary rated at the same value?
Sorry, yes 5v. Not sure why I said 12v....long day.I thought you were using 5V for power.
Whatever supply voltage you have, just buy a small SPDT relay with a DC coil voltage of the same value.
I guess I just wanted that Big Bulb look on the top of the board for right and wrong answers. I am open to other ideas though.Looks okay to me, however you can simplify it by making RY1 a DPDT relay and lighting the Green LED through the second set of contacts.
That eliminates the requirement for RY2
Why to you want to add the complications of 120V LED bulbs?
Take the "good answer" signal, invert it to drive the "bad answer" signal.A Green LED lights up if they are right and if they are wrong, a red led lights up.
Sorry, I dont follow.Take the "good answer" signal, invert it to drive the "bad answer" signal.
Done.
Like this?Looks okay to me, however you can simplify it by making RY1 a DPDT relay and lighting the Green LED through the second set of contacts.
That eliminates the requirement for RY2
Not quite. That doesn't handle the third state of no lights lit.Take the "good answer" signal, invert it to drive the "bad answer" signal.
Done.
Looks good.Like this?
Right, thats what I mean. I just need to figure out where to find them/build them and how to get the sounds on the chips.There are sound recording chips for things like teddy bears and birthday cards.
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