No problem, my current brainchild will use around 7 or so transistors, and 2 CMOS 556s. It has the advantage of being extremely power efficient, based loosely on the same tech joule thief's are (see CMOS 555 Long Duration LED Flyback Flasher). It will take a couple of days to draw the schematic (which I will post when I'm done), and a bit longer to lay it out and test it.

The potential negative of the design is it will have a 30Khz (or so) square wave, which will be fairly noisy in the RF spectrum. I don't think it will be a problem, but the possibility is there.

How would you feel about reversing D11/D12 and D9/D10 patterns, so the front is flashing the red and back is flashing the blue (and visa versa)? It would solve some technical issues.

 

Ok Bill, I leave the genius to do the magic, goodluck and thankyou so much for helping me, I wish I could repay the favor somehow...
I'll check this forum in a few days...

thanks Bill

regards to reversing D11/D12 and D9/D10 patterns...YEP, no problems...reverse it.!!!

 

OK, here is where I'm at at the moment.

You'll note that each chain has red, white, and blue LEDs. This was the technical issue I was talking about.

R1 controls the time for the total sequence (3 seconds)

R5 controls how many flashes you get, adjust for 3 total.

R7 sets the fast flash rate.

R8 is part of the Joule Thief circuit, it oscillates around 140Khz.

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The site you recommended had no bread board PCBs, they only carry protoboards, basically what I recommended earlier in this thread. Protoboards are not good for a final design though, they are meant for developing concepts. I'm going with the above bread board unless you come up with something else. You will need to come up with it though, since it is unlikely you can get the above part.

 

Thats awsome bill, I really appreciate your effort, would it be too much to ask if the diagram could be drawn like the Project: High Power LED Flasher
So I can just copy the layout and all the circuits, then solder in the components, I can get a breadboard, Ill just go to a different electronics shop.
thankyou sooo much Bill.

kind regards.

 

That is the plan. But I need the breadboard layout before I start drawing to do it right, I'm not too particular about the exact type. It needs to be around 2½" X 2" at least, more is better.

 

oh ok....well design it for 3" X 3" and I will either get the exact size bread board or i will get a bigger one and cut it down to 3" x 3"...is that a good size for you..?

thankyou

 

Part of the problem is the exact details very between boards, which is why I need definitions. I'll draw it once I see it, it's getting to be old hat.

Just photocopy whatever you come up with, or post a link.

 

Hey Bill, I finally found a shop to sell me a breadboard.....this board is 2 1/2" X 3", I hope this is OK to use.

 

heres a photo of it before I open it , just in case its not big enough.

 

That is a protoboard, it is solderless. I have no problem wiring with it, but it won't be very stable. It is also not very efficient in terms of space used.

Take a look at The 555 Projects to see how it is used. It is a wonderful tool to develop circuits, they are easy to modify and play with. It is primarily a teaching tool. The wires in mine are cut to length over 0.4" the length between holes, the insulation is cut exactly to length, and the bare wire bent 90° so the wire sits flat on the protoboard.

With protoboard the parts are 100% reusable, but the ICs must fit in the center. The strips are common to the pins going sideways. It is a giant socket with each row of 5 pins being common.

Take another look at the breadboard I drew up and referred you too. The parts can sit anywhere on it, and are soldered in. They are meant to be a lot more permanent, a final circuit. This means they can be much tighter.

If you ever decide to pick electronics up as a hobby I recommend protoboard, but not for final designs. Looks like you're getting some education on it anyhow.

Side note, there are some PCBs (solder in printed circuit boards) that use the protoboard layout, so if you want to convert an experimental design into a permanent layout it is just a matter of moving them over and soldering them in.

Another project I helped a beginner with about a year ago this is what he did.

Relay/timer design help

The thread was quite long, but we got there, do a quick review and you will so how this works. I don't expect yours to be as long, it is much simpler than his, and the design specs moved a bit. He built his using a full size protoboard, tested it out, then transferred it. It was still a little painful, since soldering is not easy for a beginner (it gets easier with practice, just like a bicycle).

If you want to go this route you will need a full sized protoboard...

You can probably tell I've done this before, and have the library of drawing to do it.

I'll be sending you a PM in a bit. All work will be done publically here, but PMs allow mailing and email addresses to be exchanged privately.

 

OK, here is where it currently is. This image will change as I continue updating the project.

 

oh thats great, starting to take shape now....

 

I haven't forgotten this thread (or project). I've been running some experiments to tweak the LED drivers. This measured 19.77ma.

I did something I don't usually do, I test selected R10 and R11 until I got a current I was comfortable with.

 

hey Bill, yeah, take your time...perfection cant be rushed.!

 

Not perfection, but this circuit is highly efficient. The LEDs would need 12V to turn them all on (9.6V to be exact), but this will turn them on brightly with 7.2V. It is a crude form of switching power supply.

I think your mates will like how little load it puts on the battery.

 

OK, this is where I currently am...

The 10µF capacitor is an oddball, I'll use only one of the negative leads wiring it to make it easy to reproduce with conventional tantalums. The idea on this unit is to make it hard for a manufacturer to install backwards. Tantalum capacitors tend to go up like match heads if abused, but they are superior parts electrically speaking. I'll send you some of the harder to get parts to make sure they fit in the board.

I'll be adding a drawing showing the LED wiring harness in a bit, on this post.

If you want to print this document just use the Windows Fax and Image Viewer, it does a nice job for hard copy. That is what I do.

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In retrospect this seems a bit silly, however...

..................Wiring Harness

 

OK, I think the drawing phase if finished. I've looked it over pretty carefully, now if I didn't make a logic error...

 

OK, two smoked resistors and one burned out iron later, here is where I'm at. I decided to build one for myself.

I still haven't finished it, but I'm getting close. I'm thinking I'll tweak it after I'm done, maybe adjust the schematic a bit and create a Rev. 2.0 version.

******************

Video Link of it working:

http://www.youtube.com/watch?v=fV9FhRKaBlU

I really don't like the way the LEDs glow when they should be off. I should have expected this, I saw it on my CMOS 555 article. Back to the drawing board, literally.

R1/C1 define the total back and forth rate, you said 3 seconds.

Since R5/R6/C3 are adjustable they are always good. They select how many flashes you get per side.

R7/C4 define the speed of the 3 flashes. You selected 3 times per second, but this seems a bit slow. Four time per second?

R8/C5 are used to generate a high frequency to create extra high voltage to drive all the LEDs at once.

 

OK, last update. Fixing the obvious problems, and some of the timing issues with this circuit I wound up with this.

You can see a short video of its operation here...

http://www.youtube.com/watch?v=3gJw7Fxmd9M

 

thats looking pretty good.... can the gap between flashes be adjusted with a trim pot or something..?.....it would be good if it could be 1/2 or 1/4 second gap....the flashing sequence looks fine.

You asked in the previous post about making it 4 flashes per second....thats fine....
or even 3 flashes per 1/2 second with 1/2 second gap would also be fine.