Need help. Looking how to buil a random timer to controll 6 lights with pre set times

I am setting up a hockey shooting station in my basement. i have a goal with a wall mounted radar gun. i am looking to use 6 d/c lights at the six positions of the net. i want the lights to come on in a random order, one at a time, light stays on for 5 seconds, then shuts off for 5 seconds and another random light will come on for 5 seconds then shut off. i want this sequence to continue for 3 minutes. i would like it to be push button start. could this be done for a reasonable amount of money. is there already a device out there i could use to do this? thanks for any help

A 4017 could be setup to count to 6 with a very rapid clock that is gated with a second 3 second timer. Both timers could be 555 chips. Search the web for 4017 and 555 circuits or, someone here with some spare time may knock up a schematic for you.

The effect will be slightly different as all lights will be on (but dull) for 3 seconds and then 1 will stay on and be brighter. A slightly more complex circuit could extinguish the lights during the off time.

Edit, this could also be achieved with a micro-controller and a few transistors but that requires programming.

Mike.

Did you forget about the random part?

Even with a micro, the random part would be hard to mimic. Controllers running set routines come up with set answers when algorithms are run. The best way to get a random number would be running an asychronous clock and having the user push a button to read the value. Since the user can't push the button at set intervals with a fast clock, the numbers would truely be random.

Maybe a pair of asynchronous clocks feeding internal timers and an algorithm that mixes the two resulting numbers when the timer data is read. Having the user push button the start instead of under program control would ensure randomness. Then a modulo six routine to extract a 1 of 6 position from that.

We had a hooty hoot owl project in high school electronics that blinked a pair of eyes (neon lights). We scavanged three or four kits to string together 8 lights, but they fired in random sequence. Just a simple RC circuit. We worked two days to try to synchronize them, then I hit on the idea to feed the output of the last back into the first and viola! It had two 75K resistors feeding the two neon lights, and a capacitor between them after the reistors. I'm not sure if it would work with lamps instead of neons. Maybe I'll play around with it to see. I seem to remember it used 100VDC but I'm not sure (it was the 70's after all).

what about using somthing like this. could i just set up 10 different programs with different patterns? all i would need then is a power supply.

usb relay board

if you're writing programs, then you could program a random generator.

What type of lamps/lights are you using?

i am just using 12v round yellow trailer lights

SAINT1000 said:

what about using somthing like this. could i just set up 10 different programs with different patterns? all i would need then is a power supply.

Click to expand...

Yes, you can use that (although it only has 4 channels). Perhaps an 8-channel version would be more suitable: https://www.ebay.com/itm/8-Channel-...uetooth-WIFI-cell-phone-control-/320981535833

In either case you'll need the board connected to a computer and a power supply to work. The program for the latter board is very simple (the former board may require using the manufacturer's library; not sure).

As mentioned, you can get the program to be as random as you want.

SAINT1000 said:

i am just using 12v round yellow trailer lights

Click to expand...

So they're probably pretty high current. Do you know how much curennt they draw?

I was actually thinking of using the usb board to controll external relays with their own power supply to run the lights. but i think the lights draw 3amps at 12v

Look up on google how to mod a pc power supply for a bench supply, just the job for a few car bulbs.

A pc or microcontroller can generate psudo random numbers, probably good enough for your appliction, unless you have a very very good memory.

dr pepper said:

unless you have a very very good memory.

Click to expand...

what do I look like, an elephant? Wait, don't answer that!!!

Hmm, ok I wont, I'm probably no better.

I have a random generator for a lights controller, the length is 256 bytes, I cant remember the pattern.

ok, it finally sank in what Pommie was talking about in post #2... something like this:

If you use cheap leaky electrolytics for both clock generators you'll probably get better randomness.

dougy83 said:

Yes, you can use that (although it only has 4 channels). Perhaps an 8-channel version would be more suitable: https://www.ebay.com/itm/8-Channel-...uetooth-WIFI-cell-phone-control-/320981535833

In either case you'll need the board connected to a computer and a power supply to work. The program for the latter board is very simple (the former board may require using the manufacturer's library; not sure).

As mentioned, you can get the program to be as random as you want.

Click to expand...

Can i program a sequence and save it then run it when i need?

note to self: you can program it to do whatever you want it to. that's the beauty of using a computer...

Mike odom said:

ok, it finally sank in what Pommie was talking about in post #2... something like this:

View attachment 69523

Click to expand...

Yes, that is exactly what I was thinking. If the fast clock is something like 10kHz and both clocks use 555s then it should be pretty random.

Mike.

Pommie said:

and both clocks use 555s then it should be pretty random.

Mike.

Click to expand...

or a single 556 )

If you choose the fast clock rate appropriately and give the slow clock a mark-space ratio of, say, 95% you can use the 5% period (a) to blank the lights to prevent flicker and (b) to gate the fast clock pulses to drive a CD4020 or similar counter and so define the required 3-minute period too.

alec_t said:

If you choose the fast clock rate appropriately and give the slow clock a mark-space ratio of, say, 95% you can use the 5% period (a) to blank the lights to prevent flicker and (b) to gate the fast clock pulses to drive a CD4020 or similar counter and so define the required 3-minute period too.

Click to expand...

The mark to space is 50% (5 seconds on and 5 seconds off).