# LED Flasher Parts



## T-Man

In the general discussion forum, I promised a part list for the flasher.
Check out the Led Flasher in the General Discussion Forum it preceeds this information.

The preceeding thread.

I have a newer strobe light thread.

I'm leaving the LED, wires, and circuit board to you.
I use a standard board cut down to size with a dremel wheel and bend the leads in the direction I want to go and use a jumper wire as necessary.
Don't forget the 9 volt battery and lead adapter.
For fun, you can use a breadboard to experiment without any soldering

For wire I use 22 guage solid.I sometimes strip the cover off the wire and use it on long exposed leads on LEDS and resistors when assembling a board.

555CN Timer IC 276-1723 (NOT to be confused with the CMOS timer)
10 uf capacitor 272-1025
1/2 watt resistors 220k 271-1132, 2.2k 271 1121, for 19 flashes per minute
100k 271-1311, 10k 271-1126 or 41 flashes per minute

With exact part numbers I don't have to get into electrical specifications of components. At times, that will confuse me.

I use an 8 pin IC socket 276-1995. That way, I can switch the IC for troubleshooting. I place the timer in the socket, after all the soldering has been done.

Ohh Yah, you will need to rig a switch. This is the draw back for a battery system. I haven't used them but a magnetic reed switch woud be nice.
Aside from model RR applications, the unit is portable. It could be used for a halloween costume. Not in the rain of course.


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## T-Man

*Flasher Variations*

555 Timer photo shows an *LED* and resisitor connected to pin 3 and the positive pin 4(because it is connected to pin 8). LED long lead faces pin 4.

To Alternate the flash (side to side), just run an *LED* and resisitor from pin 3 tp Pin 1 (negative side).LED long lead faces pin 3.
This will give you a left, right, left etc. of equal time, flash.


To give your LED a strobe look, Install a 220K to Pin 7 and Pin 8, and a 4.7k resistor to pin 2 and pin 7. The best effect is two *LEDs* connected from 3 to four. Alternating doesn't look good because the neg *LED *stays on long while the pos just flashes.

Now, We have a slow flash and a slower flash, Alternate, and a strobe flash.










LED is directonal with the long lead facing the postive and the short lead facing the negative.


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## T-Man

*Further Variation*

Using this flasher set up shown previously, the slowest rate by switching resistors, is 4 per minute. The led is on for 15 seconds and and off for 15 seconds. 
This is done using a 1M ohm (Million) resistor between pins 2 and 7 of the timer and a 100k resistor between pins 7 and 8.

To go fast, 400 flashes per minute use a 10K,1k resistor respectively.


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## tw001_tw

T-man - as I'm slowly going through the site (previous posts
and all of that) I found your 555 timer posts. Nice! Do you
have various schematics that you use to share? I found some
generic ones on line, but for comparison purposes, I'm asking.

I haven't used a 555 since college. But I am electrically minded
and electricity plays a big part in one of my other hobbies.
Have you considered getting parts else where? I comparison
shopped a handful of parts and mouser.com is way cheep compared 
to RS.. especially if you want to stock up a little on
common parts. 

Anyway, pass on those schematics you have, would you?
I was looking at these:
http://wild-bohemian.com/electronics/flasher.html
-tw

p.s. - come to think of it, I might still have some 555 notes
stuffed in an old text book


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## T-Man

*Diagrams etc.*

I like the alternate flash for the pumpkin eyes at that site. I have stayed away from transistors and stick strickly to the 555Timer.

Basically I'm self taught as of last winter. 
I reference Radio Shack because it's convenient. I'm slowly progressing, and parts are the key. 
I use four Kambach books by Peter Thorne that have various projects. 
But IC's get obsolete and expensive. The LM3909 was at 9 buck s each! Good Grief. What I try to do is bridge the gap from electronic to Model RR. I use a breadboard and many of times have toasted stuff.I have the parts for a diesel horn generator but that is a winter project. I tried using a reed relay to turn on a flasher 9 volt set up . It tested good but failed on the the track.
I did malke a 5 volt power supply powered from the track DC HO and ran a flashing unit. I will post the project in the future. I'm looking at two projects right now a 1.5 volt power supply to replace the D cell powered from the track. Today I learned about stamp technology. You can program flashing with this stuff. The site is 
http://www.parallax.com/
I think a lot of light with surface mount tech is done with this. It sounds a lot like DCC control.

Everthing else came from Google searches.
http://www.kpsec.freeuk.com/555timer.htm
http://ourworld.compuserve.com/homepages/Bill_Bowden/
http://www.mrollins.com/flash3.html

I'm sorry to dissappoint you. I had to read a lot and actually combine information from sites to do stuff. It took me months to get the flash rate to change. For some reason I blew up a lot of LED's 

If you are interested in something specific PM
Bob


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## T-Man

*Completed Flasher*

Showing both sides of the completed flasher. The white wires feed two alternating LED's aat 41 flashes per minute. Using 100k and 10K ohm resistors.My soldering tip was blunt so I cut the solder with a dremel wheel.











Thought you would like to see the end product.
Hey side by side. I have no idea how I did it but it looks good.


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## mcnay55

What size LED would you recommend for N scale. I recently switched over but haven't done any electrics.


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## T-Man

The smallest you can get. 3mm are readily available.









LONG LEAD IS POSITIVE FEED.


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