3V LED Chaser project

[audioguru2]

Hi Ibernez,
I just finished another 3V LED Chaser. This time I used orange Ultra-Bright low-voltage LEDs and they are really bright on-axis. I also used most of the changes that are in my 6V chasers.
I added another trick to this one and probably all future chasers: the LEDs chase around and around a few times then they go dark for a few seconds, saving the battery power, then start chasing again. ;D

A chaser would look cool in your guitar. Maybe it won't cause interference if you mounted the circuit and LEDs inside a metal box positioned under the strings.

An on-off switch can be wired in series with one of the battery's wires.

 

[ibernez]

So I can use Ultrabright Low voltage LEDs? that would be great because the smaller the cavity the better. I can get copper shielding tape like this

to put in the cavity. Do you think it could work under the strings with that? I think ill use the regular chaser project you made before. So can I use the "3V LED Chaser" project and just substitute with ultrabright low voltage LEDs?

 

[audioguru2]

Hi Ibernez,
The low-voltage orange Ultra-Bright LEDs I found were in a bag marked "RED" and are "no-name-brand" from China or India. They measure about 1.8V at 20mA. They have a clear package and make a blinding light beam about 20 degrees narrow. Red and orange Ultra-Bright LEDs are usually 1.8V to 2.2V and will work fine in my original 3V Chaser project.
Blue, green and white Ultra-Bright LEDs are usually 3.2V to 5V and need a 6V circuit.

You have a good idea to use copper tape for a shield. Make sure to electrically join the pieces together and connect it with a wire to the negative battery terminal on the circuit board (ground). Maybe you can wrap the circuit inside the shield with insulating heavy plastic film to keep it from shorting to the copper tape. The battery doesn't need shielding.

 

[ibernez]

Okay, I should be able to find Red/Orange Ultra-Bright 1.8V/2.2V at 20mA on allelectroinics.com or something right? But whats all this about joining the shielding to the circuit? If it's not too much trouble, can you explain why I would have to do this?

 

[audioguru2]

Hi Ibernez,
My orange LEDs are rated at 4000mcd brightness at 20mA and about a 20 degree total beam angle. They were about $5.00 for 10.

If you don't connect the shield to the circuit's ground, it will pickup the interference by capacitive-coupling due to its closeness and re-radiate the interference to your guitar strings and pickups.

 

[ibernez]

Alright, my last two questions. Sorry for all the questions. Im a Newb.
:-[ What exactly is the curcuit's ground? Can you show me an axample of what you're talking about?

 

[ibernez]

By the way, I found these--> http://www.allelectronics.com/cgi-bin/category.cgi?category=340500&item=LED-94&type=store Ill probably use them.

 

[audioguru2]

Hi Ibernez,
Those very bright LEDs are perfect. Just hope that their voltage is close to the low end of their spec so the battery will last longer.

Long ago, the "ground" connections of a radio were connected to a wire attached to a metal rod that was pushed deep into the earth. Today, the ground point of a circuit is just a common reference that all voltages are measured from. My schematic is marked showing a "ground icon":

View attachment 36423

 

[ibernez]

So I just solder a wire from the copper tape to join the curcuit at the nearest place to the negative terminal? & By The Way, when you call for 1M Audio taper (logarithmic) potentiometer, is that the same thing as 1 Meg...etc.?

 

[audioguru2]

Hi Ibernez,
All the ground points on the schematic should be joined together when you build it. The wire that you solder to the copper tape shield can be connected to any of those points.

A 1M (1 Meg) audio taper (logarithmic) pot is commonly used as a volume control in audio equipment. If you don't need a brightness control, replace the pot with a 1M resistor and the brightness will be maximum.

 

[audioguru2]

Hi Guys,
I just finished a 3V LED Chaser using orange low-voltage Ultra-bright LEDs. It is extremely bright on-axis (the LEDs have a 20 degree beam). I used the new 6V circuit with a few changes to allow it to operate with a supply of only 2V to 3V.

My daughter leaves her chaser running all the time and was getting bored with it just going around and around and around and around and around and around and around and around and around and around, etc. (I was bored too) so I decided to spice up the circuit a bit by using its spare Schmitt-trigger inverters.
The new circuit rotates the LEDs for 3 revolutions then goes to sleep for a couple of seconds (conserving battery power), then starts going again and another sleep period, etc. Looks cool. I'll post the new circuit as a new project after I revise the Veroboard wiring to include the new features, and build a 6V one to make sure it works OK.

I just found out on Google that my new very inexpensive (I got a good deal at an after Christmas sale) computer is much better than its label and its advertisments. It has the latest Hyper-threading technology and an 800MHz front-side-buss! Woopee!

 

[DaemonKhan]

I'm having problems finding the Metalized Capacitor 1nF/100V. Actually, I've been having problems finding all three metalized capacitors in the parts list. I'm so used to cermanic disc and electrolytic, the metalized ones are a mystery to me! What do they look like?

 

[audioguru2]

Hi Daemon,
Welcome to our forum.
I bought my 1nF/63V metalized poly capacitors online at www.digikey.com , their part number 495-1091ND. They are rectangular about 0.25" wide, 0.2" high and 0.07" thick. Their leads are spaced 0.2". I got my 330nF/63V and 470nF/63V capacitors there too and they look about the same, just a little thicker.
Haven't you seen my pic in the project?

View attachment 36711

 

[DaemonKhan]

heheheh...
I must have slipped my mind when I was reading through all the messages!

Thanks again for your help!

- Frank

 

[DaemonKhan]

One last question.... 

Can I power this with an "N" cell? I know that N cells are 1.5V each, but I wanted to make sure that they can be used in this project.

Do you think that a car remote battery could be used as well? Those cells are 12V though. Could they be utilitlized if resistors were added, or something?

I can easily incorporate the smaller cells into the structure, as the prop is constructed virtually in CAD, and then a master will be constructed via stereolithography.

The big issue that I have as a costume/prop designer is that things, at times, need to be durable, and compact. The AA cells are good, but do not fit the housing that was approved by the studio designer. Also, because of the fight scenes, the fight coordinators and the actors all agreed that it would be better to have the electronics compact as possible, rather than have power leads connect from a belt to device.

On a cooler note, I did find some "micro" audio and linear potentiometers that worked fabulously with the circuit design! I can make adjustments with a small phillips screwdriver for speed and brightness!

Thank you so much for all the help you given me so far! It's saved me from many a headache, and saved my hairline from being ripped out! 

- frank

 

[audioguru2]

Hi Daemon Frank,
You could power this project with two N cells or even two AAAA cells for small size. There are many 3V lithium "coin" battery cells that will work and are also very small. I have seen small battery holders for them at my local electronic parts shop.
A little car remote 9V or 12V battery would blow-up the circuit.

I am glad that you found some micro pots and am glad to have helped you.  ;D

 

[Alun]

If you must use a 9V battery you could just add a small 3V regulator to lower the voltage, and if you want maximum efficiency there are some very good cheap switching regulator chips available.

 

[DickW]

Hi All

Any chance of a PCB layout Guru? Why not just use a cheapo plug in power supply or wall wart as
the Yanks call em? Indoors of course.

View attachment 36890

 

[audioguru2]

Hi Dick,
Sorry there isn't a pcb for this project. I have made many with Veroboard. Besides, I've advanced to the 6V Ultra-bright Chaser project, and have converted nearly all 3V ones to its pausing circuit, but still running on 3V:
http://www.electronics-lab.com/projects/games/004/index.html

I designed them for extremely low power consumption so their cheap AA alkaline cells should last a long time. The 1st two I made more than 5 months ago have never been turned down and are still flashing with their original battery. So I don't think a wall-wart power supply is necessary.  ;D

 

[Codyhtml]

just get a LARGE cap and a power supply like that and it would run forever even during a power outage untell the led or somthing blows of corse