Need Electronics Assistance

Chromaflage · 02-12-2004, 06:23 PM

For all you electronics guys: I'm looking for a circuit that will strobe 4 LEDs 3 to 5 time within one second, at an interval of one in three seconds - and that will operate on a couple AA batteries for relatively long period of time. Anoyone know where I can find something like this?

Thanks,

ORS

ampersat · 02-12-2004, 06:29 PM

I'm thinking of one of those safety lights that the bicyclists wear.

I'm a little confused about the application though. Is this for your boat, your trailer, or some hot new plug?

Chromaflage · 02-12-2004, 06:31 PM

Let's just say that it's a project I'm working on the depths of the basement laboratory. Something unrelated to fishing, trailers, etc. I have one of the bicycle types - the problem is that it flashes too much and the cycles are too close together.

ORS

[ 02-12-2004, 07:32 PM: Message edited by: OregonRedside ]

BigFishFever · 02-12-2004, 06:41 PM

ORS

Lemme dig through my books on this one...I could probably whip something up with what I have in my garage....I can post a schematic once I have it figured out...

Just to clarify:
3 LEDS flashing 3-5 times within 1 second...Assuming you want them to alternate...do you want different color LEDS? I have Red/Green...

Chromaflage · 02-12-2004, 06:54 PM

BFF!! Thanks!! All one color (actualy looking at white for final project), actually four leds - all flashing at same time. d-d-d, wait, wait, wait, d-d-d, wait, wait, wait, etc. Each wait = 1 sec. Something close to that, anyway. Doesn't have to be exact, but I think you get the idea....Thanks again!

ORS

[ 02-12-2004, 07:55 PM: Message edited by: OregonRedside ]

ampersat · 02-12-2004, 08:49 PM

Sounds like a rescue beacon to me. If it is, great idea. LEDs carry a long way. It should float too!

Chromaflage · 02-12-2004, 08:55 PM

Yeah, a rescue beacon :grin: That's a great idea! [img]graemlins/idea.gif[/img] :grin:

Old Coot · 02-12-2004, 09:20 PM

Try a Princeton-Tec Aurora or Zipka headlamp. About thirty bucks. Each has four or five lite modes, two of which are all-LEDs flash in unison at different rates.

Conspiracy Theory · 02-12-2004, 11:04 PM

OregonRedside,

Try your local High School or College electronics classes. Sometimes they need projects and they might be able to design and make one custom to your specs.

Good luck on the project.

BigFishFever · 02-13-2004, 04:09 AM

ORS

Ok, I have the basic schematic figured out...I just have to find the IC chip to control it and provide the pulse.
I will have to double check, but you might be able to make it smaller, by using only 1 AA battery...but I will tinker with the idea, and see if I can figure out the draw of the circuit and see appx how long the battery will last.
I am going to be outta town this weekend, but will continue to look into it.
4 LEDS flasing in unison...3 seconds between each flash..
I can throw this on a breadboard and see what happens.....I will let you know!

BigFishFever · 02-13-2004, 06:01 AM

ORS

Ok, well work has been slow this morning so I was able to do a bit more research... I was going to post the schematic, but umm well havent figured that part out yet.

As for the schematic, it is a fairly simple schematic..I have run into a couple of snags...but added a feature that "might" be useful for your application.

There is a part of the schematic in dashes...this is the optional part...if you put a photoconductive cell in place when daylight hits, it should shut the circuit off, and conserve batteries.

The only problem that I can see on the schematic as of right now, is that it will flash at a the desired rate...but not d-d-d wait wait wait d-d-d as you described but d wait d wait d wait...

I will continue to research to see if I can find a better chip, but this might give you something to play with over the weekend.

The IC chip, is a MAXIM ICL7660 and you should be able to pick up an equivalent at Radio Shack, or via the website from the manufacture...While I was in School, we called the Maxim CS support, and they sent us chips much more expensive than this for free.

I will email ya the schematic...if you want post it up...if not let me know that you got it!

Gus Orviston · 02-13-2004, 06:14 AM

555 timers work great for stuff like this and there are a lot of documented circuits. It is a programmable timer that has been around since the beginning of well, silicon. The maxim sounds like it could do it too.

Combined with binary counter and drive the LED enable off of one of the higher bits would give you your run , off, run, off cycle.

bits from a basic counter
0 LHLHLHLHLHLH
1 LLHHLLHHLLHH
2 LLLLHHHHLLLL

What you would want to do is drive the LEDs with Bit 0 and gate them with Bit 2, by a Boolean AND, or NAND depending on the logic config with the LEDs.

The output would look like this if enabled when bit 2 was high (like using an AND gate)

LLLLLHLHLLLLLHLHLLLL get the idea?

Use variations of a counter to get what you need.

The you need to drive the counter with an OSC etc..

See what the Maxim can do for you, and let me know if you guys get stumped. I am a logic designer and have done tons of stuff like this, and it is pretty easy. The key is finding the cheapest way and the most reliable. KISS.

gus

BigFishFever · 02-13-2004, 06:23 AM

Hey Gus....

Sounds like you have a ton more experience on this than I do...I went to school for this stuff, then after graduating moved into a different sector (networking etc)
Would you like to check out the schematic, and see what you think? Maybe we can come up with something that would knock this out...

555 timer sounds like it would be easier to get the complete result...

Lemme know and I can forward ya what I got...then let you rip it apart...been to many years since circuit design, but I enjoy it!

Mello-Yello · 02-13-2004, 06:24 AM

Seems like it would be a heck of a lot easier to just have a steady LED, and blink your eyes 3 to 5 time within one second, at an interval of one in three seconds. No batteries required! [img]graemlins/dork.gif[/img]

BigFishFever · 02-13-2004, 06:28 AM

Only problem with that is getting everybody programmed to blink at the same time...

Chromaflage · 02-13-2004, 12:01 PM

Holy smokes!! :shocked: Thanks for all your input and the effort by BFF!!

Got a schematic from him today. It didn't take long for this thread to end up way over my head!! I'm not an electronics guy - I guess that's why I asked the Q.

Gus - thanks, and yes - simple and cheap! That's what I'm after.

Any of you guys need (legal :grin: ) chemistry or toxicology help, I'm there!

ORS

[ 02-13-2004, 01:03 PM: Message edited by: OregonRedside ]

Cool Texan · 02-13-2004, 12:05 PM

Quote:

Originally posted by Mello-Yello:
Seems like it would be a heck of a lot easier to just have a steady LED, and blink your eyes 3 to 5 time within one second, at an interval of one in three seconds. No batteries required! [img]graemlins/dork.gif[/img]

[img]graemlins/dork.gif[/img]

Gus Orviston · 02-13-2004, 12:12 PM

Yea, I got about 20 years designing CPU/CS embedded controllers, PC motherboards, addin network cards, ASICS and so on. Easy stuff, and there is a miriad of choices to solve this problem. I would definitely like to aid in , and at least review your circuit for timing issues and resistor/led config- optimum current to light the LEDs and so on.

I am off to Taiwan (go figure) Monday and won't have access to books/data sheets. but go to a library and look up 555 timer circuits and there will be huge catalog of solution already done and ready for building. This bad boy is a mainstay in just this sort of thing.

Let me know when you need more information or a bit of advise...I will be online but out of time zone considerably for the next 2 weeks. From Twn I head to Europe and them back home...

hey,shoot me the schematics too, I will throw my 1.23 cents at them..

gus

[ 02-13-2004, 01:13 PM: Message edited by: Gus Orviston ]

BigFishFever · 02-13-2004, 12:17 PM

Gus...I will shoot you the schematic I drew up...dont laugh to hard

you have much more experience on this than I do..

ORS I hope one of these will work for you..and as for the chem/tox thing...well dont know nothing bout that..I am just a redneck with a degree that is sitting idle along with my fishin poles!

Chromaflage · 02-13-2004, 12:43 PM

BFF - I'm not that far off from you... :grin:

ORS

BigFishFever · 02-13-2004, 12:52 PM

ORS

Ok got the schematic off to Gus...I am hoping that he doesnt tear me apart to hard

and as the greatest saying goes..

"A rifle, a shotgun and a four wheel drive..." us country boys CAN survive!

HeavyMetal BankFisherman · 02-13-2004, 12:52 PM

You might find what your looking for here.

BigFishFever · 02-16-2004, 10:29 AM

ORS

Ok, it looks like Gus is giving me a re-education...the schematic I shot ya, is not going to work...He has provided me with some info, and we are going to dig a little more and see if we can come up with something..

I will let you know!

Chromaflage · 02-16-2004, 03:08 PM

Cool! Thanks again, guys!

ORS