light timer

[tidos76]

I need some help. I am making a drag tree. It doesnt have to be perfect. I have everything figured out except one thing. I need to light up 3 bulbs anywere between .5-1 sec then off. when they go off i need one buld to come on and stay on till i reset it. I do not want to have to program a pic. I hope someone can help me with only using simple easy to get stuff, due to the fact that i'm broke. thanks in advance!

 

[user_88]

This shouldn't require anything too complicated .....

After the first three bulbs turn on, and then off, in sequence, is there a fourth bulb, or do you mean that one of the first three turns back on?

Are the bulbs something like 100W incandescent? .... or something else?

 

[tidos76]

no sure what bulbs yet. but there are 3 yellow 1 green. yellow on for .5-1sec as soon at the yellow turns on the green turns on with no delay between yellow(off) and green (on)

 

[user_88]

So ... just to be clear .... you don't want any pause or gap between any of the yellow lights ..... right?

 

[tidos76]

correct all 3 yellow lights will(in a sence) act as one light.

 

[user_88]

Check back.... later....24 hours .... There ought to be a circuit that you can build .... or take a look at....

 

[Andy1845c]

Don't you want the yellow lights to sequence like this animation?

YouTube - Lego NHRA .500 Full Tree Practice Simulation

Do you want a mini one using LEDs, or a full size version?

My dad made a full size version back in the early 80's. He used colored outdoor flood light bulbs and timer relays to control the sequence. It sequences just like the animation.

I pic would be the simplist way to do it if you have access to a programmer. If you don't, I am thinking somthing along the lines of using a 555 timer and 4017 to sequence the lights, and possibly an SCR to latch on the green lights.

Let me know what you would like to use for bulbs and I will see if I can dig something up.

 

[user_88]

possible circuit .....

I have a trial circuit for your light tree ....
The simulation program seems to show that it does what you originally requested:
First step ..... yellow
Second step .... yellow, yellow
Third step .... yellow, yellow, yellow
Forth step ..... green, and all yellows turn off.

It is not perfected yet, one or two bugs... The main problem being that it keeps recycling back to the start after the green light is turned off. I think that problem might be fixed with a transistor ... grounding out the system clock when the green light turns on. That is more of an analog problem, and could not be simulated with the B Spice program.

The only other thing that I'm not certain about is the initialization and reset.
I am guessing that a power off/on cycle will do this job. The first thing to do would be to get a few of the digital logic chips and build a test circuit.
.... Not too many parts are required for this... just some digital ICs, and a few resistors, and capacitors.

Basically, this circuit is just the digital logic that is required for the timing signal.
Once you get the timing to work just right, you can think about the relays and lights. .... Also, you will need to put a few parts together to make a clock generator .... nothing too difficult there.

If you want to take a look, send me a PM ... private message .... with your email. You can download the simulator ..... B-Spice Lite, for free .... and see if you think it will work.
**broken link removed**

I would post the circuit on the forum, but the simulator is not amenable to that. .... So just send a PM.