very simple project--probably

[Paul Winters]

I am trying to figure out the easiest way to have a bunch of LEDs
alternate glowing continuously. I want to open a box and the lights
to go on intermittently. Would I use a 555 timer or something else.
And if so, how?

thanks, Paul

 

[Paul Winters]

I am trying to figure out the easiest way to have a bunch of LEDs
alternate glowing continuously. I want to open a box and the lights
to go on intermittently. Would I use a 555 timer or something else.
And if so, how?

thanks, Paul

And the sequencing should seem fairly random.

 

[[email protected]]

And the sequencing should seem fairly random.

Hmmm, go to the dollar store and pick up a few 1$ fiber optic trees
with RGB LEDs in them. These things cycle across all kinds of colors
too. When you get bored of them, lots of parts are already laid out
for you to tinker with.

 

[Don Lancaster]

And the sequencing should seem fairly random.

Use a PIC, of course.


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com

 

[Eeyore]

I am trying to figure out the easiest way to have a bunch of LEDs
alternate glowing continuously.

WTF does that mean ?

Graham

 

[D from BC]

I am trying to figure out the easiest way to have a bunch of LEDs
alternate glowing continuously. I want to open a box and the lights
to go on intermittently. Would I use a 555 timer or something else.
And if so, how?

thanks, Paul

uC preferred but if that scares you then..

MLS (maximum length sequence) generator.
This uses a shift register + logic gates.
Use RC networks to get the glow effect.
D from BC

 

[Robbo]

I am trying to figure out the easiest way to have a bunch of LEDs
alternate glowing continuously. I want to open a box and the lights
to go on intermittently. Would I use a 555 timer or something else.
And if so, how?

thanks, Paul

Make up 3 or 4 strings consisting of LEDs (say 4 leds), a current limiting
resistor and a "flashing" LED (the ones with the integrated flashing
circuitry) in series. Put the 3 or 4 strings all in parallel. The flashing
LEDs flash at a slightly different rate to each other giving a random
flashing effect. "Mix" up the locations of the LEDs so they are not all in
the same area / line etc. Works well for little christmas trees.


See how this goes:

|---->|---->|---->|---->|------>|----/\/\/\/---------|
| |
|---->|---->|---->|---->|------>|----/\/\/\/---------|
| |
|---->|---->|---->|---->|------>|----/\/\/\/---------|
| |
|---->|---->|---->|---->|------>|----/\/\/\/---------|
| |
| ^ |
pos flasher gnd/neg


It worked for me, ymmv.

 

[neon]

7475 Chip Use It As A Counter And It Will Cycle Continiously At Whatever Clock Rate Is Set. Use Lm555 And A Pot And You Can Set The Scanning Frquency. Done That For A Cross With Superbright Leds [[ Inpressive]].