Gidday,
Newbie to all this ...But I've got no Idea where to start...went to 2 Electronic stores Today, and asked this Question... I'm Trying to Light a Scale Model for a Client...Tricky thing is... there is a large Control Panel with a Rainbow effect behind it..Still with me?...I'm using 3 RGB leds ,but I would like them to come on in a delayed order EG..1. then 3...then 2..basically the 3 colour leds out of sync ,(not flashing) but to switch on with a delay in order to cycle thu the different colours..(rainbow effect).. it's a pity that people that work in electronic shops only know how the cash register works. My only other option is to wire them individually to 3 separate switches,but there has to be a another way?

 

Gidday,
Newbie to all this ...But I've got no Idea where to start...went to 2 Electronic stores Today, and asked this Question... I'm Trying to Light a Scale Model for a Client...Tricky thing is... there is a large Control Panel with a Rainbow effect behind it..Still with me?...I'm using 3 RGB leds ,but I would like them to come on in a delayed order EG..1. then 3...then 2..basically the 3 colour leds out of sync ,(not flashing) but to switch on with a delay in order to cycle thu the different colours..(rainbow effect).. it's a pity that people that work in electronic shops only know how the cash register works. My only other option is to wire them individually to 3 separate switches,but there has to be a another way?

The stupid ones rulle today. We don't deny that.

What you need is 3 switches. Hoever activating the first switch will activate the "timer555_2" integral circuit, after the timer waits 15 sec it will activate the second switch and the "timer555_3" circuit which will wait 15 sec and activate the third switch.

 

Welcome to AAC!

A microcontroller based solution would be the easiest and give you the most flexibility.

it's a pity that people that work in electronic shops only know how the cash register works.

Most people working cash registers know little about the product they sell. Why would an electronics shop be any different?

When I was a server in a restaurant, I took cash and knew how to make every dish on the menu; but only because I also did shifts as the "American" and "Chinese" cook.

 

A simple approach would be to just automate to whatever sequence, color and intensity you want using a small micro-controller. The circuits are not that complex and there are hundreds of programming samples out there on the web. While there are many to choose from and any number will do the same thing I would suggest using an Arduino. The Arduino Uno is available from dozens of retailers globally. I suggest a micro-controller solution only because it offers considerable flexibility as to the effects you can get. Also because there are, as I mentioned, hundreds of circuits and code samples available online, especially for doing things with RGB LEDs.

A typical LED strip with 5050 LEDs and built in resistors can be powered from 12 Volts DC. Likewise once programmed the Arduino Uno can be powered by 12 VDC. Here is an example of what driving 5050 12 volt LEDs would look like.



The DIOs are outputs from your micro controller. The drawing is merely an example. The FQP30N06 are just cheap MOSFETs used as switches to drive the LEDs. You can pretty much have whatever you want as to sequence and effects. This stuff is not really complicated and easily tossed together.

Ron

 

An MCU would work, do you know how to program it?

 

The FQP30N06 are just cheap MOSFETs used as switches to drive the LEDs.

You got me there. I thought you had found an inexpensive MOSFET. At a dollar each in qty around 100, I'll stick with 2N7000 or BJT's.

 

You got me there. I thought you had found an inexpensive MOSFET. At a dollar each in qty around 100, I'll stick with 2N7000 or BJT's.

OK, relatively inexpensive at a buck a pop? I like and use the 2N7000 MOSFET and they do just fine. The reason I tossed the MOSFET I did out there was I haven't a clue what the actual load current will be. The drawing using the FQP30N06 was just an example.There are also plenty of circuits out there using the 2N7000 with micro controllers like the Arduino or even a simple switching transistor like the 2N2222. So yes, depending on the load a 2N7000 will do just fine at well below half the cost of the FQP30N06 MOSFET I posted.

Ron

 

One more vote for a microcontroller with a few transistors as switches on its outputs. Arduino Uno is easy, well documented, and ubiquitous. There are also smaller versions if size is an issue. Arduino mini, micro, etc. I've lost track of the names and which of them are still in production.

Right now, my personal favorite for balancing small size, good performance, and still being convenient (USB programming and debugging, Arduino IDE, etc.) is the Adafruit Feather line. That said, there are dozens, maybe hundreds, of other options that would do this job easily with minimal programming.

https://www.adafruit.com/product/27...PZs3EdSLM-IPtMtoWi-tm6Z0FmKSXTNRoCaOEQAvD_BwE

 

Hey Guys, Thanks for your Help...was expecting to be told to" Bugger off Idiot"..so I was going to go with this...Latest Arduino Compatible Nano V3.0 ATMEGA328P + USB Cable with soldered pins...$8 bucks? is that what I'm needing? Think Dog flying a Space Shuttle and thats my electronics level.

 

Latest Arduino Compatible Nano V3.0 ATMEGA328P + USB Cable with soldered pins...$8 bucks? is that what I'm needing?

That would work likely and I say likely because it is likely a Chinese knockoff board which is why you see Arduino Compatible. When it comes to the Chinese stuff some works fine and some not so good. A genuine Arduino Nano is about $22 so if a Chinese knockoff works for $8 then it's fine. Some members here have more experience with the China boards so hopefully someone can comment.

What is needed is some data on the LEDs you plan to use? That gets real important real fast. Also what exactly you want to get done beyond what you already mentioned.

Ron