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.

The circuit only requires one relay (or MOSFET) and 16 diodes.

 

You only posted one way.
But you need one diode on each line to isolate the lines.

Yup you are right, makes sense now.

Thanks,

 

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.

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 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.

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.

 

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?

 

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?

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 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.

Sorry, yes 5v. Not sure why I said 12v....long day.

Thanks,

 

I have made a few adjustments and wanted to see if anyone could check my work? Instead of going with a single12v LED for a correct answer, I am going to go with a 120v LED Light bulb mounted to the top of the board. In order to do this I had to add a few relays. If someone could let me know if I did this correctly, or have any suggestions to simply or make it better please let me know.

Thaks,
Jimmie

 

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?

 

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?

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.

 

A Green LED lights up if they are right and if they are wrong, a red led lights up.

Take the "good answer" signal, invert it to drive the "bad answer" signal.

Done.

 

Take the "good answer" signal, invert it to drive the "bad answer" signal.

Done.

Sorry, I dont follow.

 

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

Like this?

 

Take the "good answer" signal, invert it to drive the "bad answer" signal.

Done.

Not quite. That doesn't handle the third state of no lights lit.

 

Like this?

Looks good.
If you want a big bulb then using a 120V one is an easy way to go.
But they do make large 12V LED bulbs such as these as an alternative, if you want to avoid any high voltage in the system and having to plug into the wall. With that you could go back to one relay.

 

Please forgive me in advance of my next question(s).

I am one who does not know when to stop so......

One of my quiz boards is going to be bird names listed on the left with bird pictures in the body of the board. The junior ranger will be required to match the name with the correct photo using the device described above. Now for the next step.

How cool would it be if when the junior ranger made the correct selection not only did they get a green light, but they got a sound effect of that particular bird that they selected correctly? They match the Blue Jay name with the picture of the Blue Jay and the light turns green and they get a sound effect of the Blue Jay skawking.

My question is going to be two-fold:

1. Can you look over my revised schematic and see if t looks correct to do whats desribed above? I realize I could simplify a bit with DPDT relays but I am starting with this one for now.

2. Can I build simple boards to act as audible devices that could record or save an uploaded sound, then play it on the presence of applied voltage?

**EDIT**
I have simplified the design a little. New JPG uploded.

 

You could add sound as shown, but I don't know offhand what the best way is to generate the various sounds.

 

There are sound recording chips for things like teddy bears and birthday cards.

 

There are sound recording chips for things like teddy bears and birthday cards.

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.

**EDIT**
I actually found a few on Ebay/Amazon but they are like $9 each. I dont want to spend over $150 on sound modules so I will have to keep looking for other ideas or scrap that part of the project.

 

Well I found this which looks like exactly what I was talking about. It has 20 channels, triggered by individual Neg(-) signals. Signal (1) plays file #1, signal (2) plays file #2, etc. Only problem is its $75. I don't think the Ranger group will want to opt for that costly of an upgrade. If anyone has any other outlets for cheaper solutions let me know.

http://www.amazon.com/Channel-Sound...e=UTF8&qid=1459433915&sr=8-1&keywords=FN-BC20


Thanks,