John Fields
Professional Circuit Designer
+12V>---------+--------------+-----+-------+--------------+
| | | | |
| | | | [510]
[10K] [1M] | | |A
| | | | [LED]
| +--[10M]--+ |R2 | |
|R1 | | [10K]<---|-\ E
[10K]<-+-|+\ | | | >-+-[10K]--B 2N3906
| | >----+-----|------|+/ | C
IN>--[100K]---|------|-/U1A | | U1B| |+ |
| LM393 |+ | | [22µF] |
| [10µF] | | |C2 |
| | | | | |
GND>----------+--------------+-----+-------+---+----------+
Mr. Fields was kind enough to design this circuit for me, to simulate the gradual ramping up and down of a incandescent lamp, instead of the instant on and off of a LED.
Once again Mr. Fields...thanks
Working with the 4017 and a 555 is tons of fun, and can be adapted in MANY ways...Ive built MANY lamp chasers with them (I have several MODEL AND PROP making buddies left over from my days in the film business, and they love to use this for interior lighting)...and they always work. I have a tattered photocopy of a Popular Electronics tutorial on working with the 4017, with many many schematics of different effects that an be made. My favorite is the fact that you can daisy chain them together, and easily make a 10, 20,30.....etc lamp chaser.
I once built a 4017 Squib detanator for bullet hits, to simulate machine gun fire in movies. It ws used hundreds of times in many different movies, by may different effects guys...much better than the traditional "Nail Board" method. I built many customed designed units for FX buddies, including tiny ones that could be carried in the costume of an actor, to detonate bullet hits worn by the actor... again, a huge technalogical advancement, as prior to this, often a cable was run down the actors leg to a "Nail Board" to detonate the Squibs all over the body... a cumbersome, and difficult to hide from the camera way of doing things.
You can drive low voltage incandescent lamps instead of using LEDS thereby simulating a nice delayed dimming of each bulb, just add a cheap switching transistor to each output to drive the lamp directly