The circuit described in post #18 would be a NAND:

For the gate you're using, current sink capability is greater than source.

 

Main how I hate these cartoon wiring diagrams!

I think a couple of people have at least hinted at one potentially significant problem. By having the red LED in series with the inputs of the of your AND gate, you are considerably increasing the complexity.

Assuming the cartoon now has the actual resistor values used, you have two 470 Ω resistors in the LED path and then a 1 kΩ resistor going over to the base.

Assuming a fresh 9 V battery and that the red LEDs have a 2.2 V forward drop, the current through the LED, when on and ignoring the base connection, would be

If = (9 V - 2.2 V) / (470 Ω + 470 Ω) = 7.2 mA

That means that the voltage at the bottom of the LED would be about 3.4 V.

Assuming that the green LED has a forward voltage of about 2 V, then the base of the bottom transistor, when on, would be somewhere around 2.7 V.

That would make the base current in the bottom transistor about

Ib = (3.4 V - 2.7 V) / 1 kΩ = 0.7 mA

If the top transistor is off, that current will still flow in the green LED, which may well be enough to make it visibly light up.

The big question is, if both switches are on, what is the emitter voltage at the top transistor. Is the bottom transistor actually saturated? If so, then the emitter of the top transistor would be at about 2.3 V and the base would be at about 3.0 V, making the base current about 0.4 mA. The top transistor is NOT saturated, so it's collector current should be well above the 7 mA needed to saturate the bottom transistor.

This circuit has a LOT to be desired.

 

Trying to draw this to a noob! Difficult.



Or maybe the cartoonish way!

 

The "cartoonish way" isn't good. It will be trying to put something around 4 V across the LED since there's no current limiting mechanism.

 

In the right hand side of the schematic in post #8 remove the green LED from between the emitter of Q2 and ground. Connect the emitter of Q2 directly to ground. Break the connection between the top of R1 and +9 volts. Connect the anode of the green LED to +9 volts. Connect the cathode of the green LED to the top of R1. If you can't read schematics (Which I suspect you can't as you have refused to post schematics when requested,) then from the picture in post #13 Unsolder the red and green wires in the bottom right hand corner and solder them together.
In the top right hand corner unsolder the horizontal red wire from the top of the 240 ohm resistor. Solder the cathode (The wire next to the flat on the LED.) of the green LED to the top of the 240 ohm resistor. Solder the red wire to the anode of the green LED. It should now work correctly.

Les.

Thank you very much, it works just as i want it!!

 

greater than source.

What program did you use to create this circuit that i can use it to create schematics too? And post #21 is an AND. It would be a NAND if the green LED was switched parralel to the two transistors.

 

The "cartoonish way" isn't good. It will be trying to put something around 4 V across the LED since there's no current limiting mechanism.

Yes, I didn't realize that. Got the cartoon from instructables. Should have known better!

 

Got the cartoon from instructables. Should have known better!

People who draw schematics like that generally don't know what they're talking about. It should embarrass anyone older than 10 or 11 to be drawing circuits like cartoons.

 

What program did you use to create this circuit that i can use it to create schematics too?

I use the free version of Eagle; a very old version. The only feature I like in the newer versions is the ability to have selective overbar in text. They way they rearranged the main menu and changed icons makes it more productive for me to stay with version 4.13r1. I modified some libraries and am not inclined to make any of the changes again.

And post #21 is an AND. It would be a NAND if the green LED was switched parralel to the two transistors.

The circuit in #21 is a NAND. Two HIGH inputs give a LOW output. It would be an AND if the output was taken from the emitter of Q2.

 

Here's the download link for Eagle:
https://www.autodesk.com/products/eagle/free-download

The last time I tried to use a newer version, it was asking me to create an account.

If you want an older version, I probably have the zip files if they're not still available from Autodesk.