6V Ultra-Bright Chaser

[audioguru2]

Hi Guys,
I have been making a bunch of this project:
http://www.electronics-lab.com/projects/games/004/index.html
hasn't anyone else?

I have also been converting all my 3V chasers into this circuit, modified for 3V as in the project's text, they look more interesting and their battery lasts much longer with its pauses during the chase.

My local far-eastern supplier has let me down. I bought 20 no-brand ultra-bright blue LEDs but didn't test them all in the store. While building a project, I tested them and ended-up with 10 defective. They were all blue but the bad ones are dim, very narrow angle or don't fit my holders. I'll order good quality name-brand Agilent or Liteon from now on.
[move] ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D[/move]

 

[Alun]

Audioguru,
I hope you tested the LEDs with a higher voltage than 3V, most blue LEDs have a forward volt drop of about 3.5V. You're very lucky to get half of them to work at 3V and if this is the case then they're quite good quality.

I hope you've not thrown those LEDs away!

 

[audioguru2]

Hi Alun,
I spec LEDs that are less than 2V for my 3V project, usually red but I have also used orange and yellow.
I spec (about) 3.2V LEDs for my 6V project, usually blue, ultra-bright green or white.

Of course 3.2V LEDs won't work in the 3V project, especially when the battery runs-down to 2V. Likewise, 2V LEDs in the 6V project will probably cause smoke damage.

When converting my old 3V projects to the new circuit (changed for 3V as listed), I keep the original LEDs and battery and just simply change the circuit board.

I measured 3.1V for the dim blue LEDs and looking closely I can see air-bubbles on top of the chip inside. Their manufacturer didn't bother to test them with a photocell. :

Agilent sells quality LEDs with brightness groups (for a small price difference) and colour tint groups for the white ones.

I use a 9V battery and a 1K current-limiting resistor to test LEDs. ;D

 

[audioguru2]

Hi Guys,
Watch out for those Cmos ICs in this project. I think I zapped one with static electricity by simply putting a finished project into a plastic bag (maybe removing it caused the damage). Since it is very cold here in winter, the air is very dry and static electricity builds-up on everything that insulates and moves. I don't like to use a humidifier because it makes the windows fog-up and condensation runs down and ruins the window frame. These windows have 2 separate pieces of glass and have a sealed air space between. When it is really cold, ice forms on them indoors, even without a humidifier. The window in the ceiling above where I sit drips on me sometimes. Right now there's ice on both sides around the rim, inside and outside.

The LEDs flash brightly, the speed and brightness controls work, but the LEDs shine dimly for the total duration of the HC4017's outputs. I think the brightness PWM oscillator inverter got zapped and the spark probably jumped in through the brightness pot. For audio circuits I usually ground the case of pots to avoid hum from your hands. That should also be done on this project.

Today I took back the defective blue LEDs to my local electronic surplus store. I wanted my money back but they were very sorry and gave me a bag of their newest, brightest ones instead. They are all perfect and extremely bright, fairly wide-angle too. In a few days, look up into the sky at night. You will see my Ultra-Bright extremely bright blue LEDs reflecting off the ionosphere or the moon! ;D
A guy here was arrested for temporarily blinding airline pilots with a laser pointer. They were in the air, he was on the ground. I might be next. ;D

 

[EnigmaOne]

Last time I upped my inventory of solid state lamps, I bought from BlackFeather Electronics. Cost was good, and they generously adjusted their pricing in accordance with the quantities ordered. All-in-all, they were very good and fast on the turn-around.

They've since moved their brick-n-mortar and I haven't had a chance to do any ordering from them in the interim. They may be worth a look on your part.

A guy here was arrested for temporarily blinding airline pilots with a laser pointer.

Was he like the one in New York, who was supposedly painting the eyes of a commercial jet pilot (flying at something like 5000 feet or more at 2 or 3 hundred miles per hour) with a handheld green laser pointer?

 

[audioguru2]

Hi EnigmaOne,
I never heard of BlackFeather.

Yeah, that was the guy with the laser pointer. I think my new LEDs are brighter!
Let's see. At that speed, the Doppler frequency shift must make a green laser look kinda blue if it was coming toward you, don't you think? Then my new blue LEDs will look kinda purple. ;D

 

[audioguru2]

Hi Guys,
Look up at the moon! It is flashing blue because my latest ultra-bright chaser is shining on it. ;D ;D

Yeah, I've finished my 10th and final ultra-bright chaser, all with Veroboard (I could make one quicker than you could etch and drill a PCB). I've also re-built 6 of them to have the latest circuit with the pause, 3V and 6V ones. I've sold some, gave away some to friends and family and kept a few.
The latest one is the brightest of them all. Its LEDs are blue, 5000mcd, 25 degrees total angle and measure only 2.83V at 25mA. At full brightness setting it is absolutely blinding and lights-up one end of my family room from its other end.

It was fun making them all but 3 of the Chinese pots failed early, both brands. It was a nuisance to replace them but luckily they are cheap and available locally.

Today I got a $5.00 rebate cheque and thanks from Energizer, for their 24 AA alkaline cells I bought on sale just after Christmas. When you subtract the rebate from the low price I paid, I got them for almost nothin'. They are stamped "best before 2011" too. ;D

 

[audioguru2]

Hi Guys,
Sure my ultra-bright chasers are still working with their original batteries, and I have them chasing around almost every evening (my wifey :-* keeps saying, "Turn-off those blinding things! >"). Since their light is fairly directional I just point them away from her. ;D

One of them has a problem. When the LEDs are supposed to be off, they are all dimly lighted.
I traced it to one LED that has a leakage current when it has only 2.8V of reverse bias.
I thought all LEDs have a maximum reverse voltage rating of 5V, but my bad LED is a no-name-brand ultra-bright green Chinese one. Maybe its manufacurer doesn't care about ratings. Luckily I have a spare one, I bought a bag of 10 for a discount and it actually contained 11. ;D

View attachment 37048

 

[ante1]

Hi Audioguru,

Now you know why they gave you the extra LED! ;D ;D

Good work, with service bulletins and everything!

 

[audioguru2]

Thanks, Ante. ;D

I remember the details of when I bought those green ultra-bright LEDs. The storekeeper gave me an extra one because when I tested them, one was red instead of green. Maybe he thinks they change colour after a while! ;D ;D

 

[ante1]

Hi Audioguru,

Could be it was a mulitcolor LED and he connected it the wrong way!

 

[audioguru2]

Hi Ante,
I bought a two-wire alternating red-blue LED from him. He doesn't have four-wire RGB LEDs yet.

I just finished replacing the bad LED. On my low-voltage ohm-meter it measures about 14M in both directions and on diode test measures about 1V in both directions.
A good one measures >20M in both directions, lights dimly for diode test and measures about 2.3V.

I discovered some new fun with my ultra-bright chasers. With one of them chasing quickly around and around and shining on my big white closet doors about 7m away, if I get in the way of the beam my shadow is very clear and appears to move around and around! Cool! ;D
[move] 8) 8) 8)

 

[ante1]

Hi,

I bet you have one of those in your bathroom too! Which color is it? 8)

 

[audioguru2]

Hi Ante,
I don't need one in my bathroom. They are bright enough to shine all the way across my livingroom, down the the hall and around the corner. They even shine under the closed door.

I can make my whole neighbourhood glow when it is foggy at night. ;D

 

[ante1]

Hi Audioguru,

You could put a “chaser” on you dashboard made from these alternating red-blue LED:s and it will get you through a traffic jam in no time!  8)

 

[audioguru2]

I nearly got arrested for having a blue ultra-bright LED blinking on my dashboard. It was in summer but the law reserves blue flashing lights only for snow plows. He, he. ;D ;D

 

[ante1]

Just put a blade on the front bumper then!  ;D