Strobe Lighting For The Enterprise-A

[scifimodeler]

--------------------------------------------------------------------------------

Hi All – I hope someone can help me with a lighting question. I am building the 1/350 Enterprise-A kit. I am trying to setup LED’s to do the strobe light effects. I followed a number of you tube tutorials and got the basic setup complete. When I put power to the circuit I do sort of get a strobe effect. However it just doesn’t seem right. The LED lights very dim then strobes, and then come on very dim then strobes over and over. I do not think the dim part is correct. Has anyone come across this and know what I am doing wrong or is this normal.

Thank you all
John

 

[Grendels]

What are you using to strobe the LED? Is it a 555 chip, or some other circuit?

 

[scifimodeler]

I am using the 555 timer chip. I first thought it was a short somewhere so I started over with all new parts and ended up with the same thing. I searched around youtube to find maybe a different way to do this but everything I found was not really done for people like myself that have very little electrical skills. For me it is easier to understand setting it up from a very simple diagram. .. Thank you

 

[Grendels]

A few quick questions:

What are you using for the source voltage?

What color LED are you using?

What is the value of the resistance right next to the LED?

The only thing I can think of is that you have the value of the resistance for the LED a bit too low. Try increasing it a bit.

 

[scifimodeler]

Thanks John.. I am using a 100 ohm resistor. I didn't think of putting a higher value resistor on. I will give that a try and let you know. By the way... Your videos are awsome... Thanks

 

[Grendels]

Your welcome, if that does work, I would replace that LED. Running too much current through it will shorten its life.

 

[scifimodeler]

This is my setup John. Maybe this is the way it should look but it does seem a little funny. I am using a 555 timer setup this way.
220uf Capacitor between Pin 1 and 2 (Neg of capacitor is in pin 1)
Jumper from pin 2 to pin 6
Jumper from pin 4 to pin 8
10K resistor from pin 6 to pin 7
100 ohm resistor from pin 7 to pin 8
1amp diode from pin 2 to pin 7
Pin 1 to a 100 ohm resistor to neg of led
Positive of led to pin 3
Pin 1 to 9V neg
Pin 8 to 9V Positive

The led come on dim then strobes..

Thank you

 

[Grendels]

I think that is the problem, the resistance on the LED is far too low. You have a 100 ohm resistor there and If it is a white, blue or green LED, you need a 320 Ohm resistor there. If it is a red, yellow or orange LED, you will need a 390 ohm resistor.

The voltage you input into the 555 is the same voltage that comes out of the circuit. So you have to put a resistor on the LED that is for the source voltage at the very least.

 

[scifimodeler]

Thanks John... I'll give her a go..

 

[Grendels]

Let me know what happens...

 

[hooterville75]

John I know this thread has nothing absolutely to do with me but I just wanted to chime in and say Thank You for taking the time out of your busy schedule to help any and everyone that may need help that you have the knowledge and answers to help them. I truly appreciate all you do for people on this site. People like you are what keeps this hobby so much more fun for us new guys. So Thank You again. Thank you to everyone else for that matter. This forum is an absolute great fun time.

 

[Grendels]

I am glad to help when I have the time, and I am happy that you like this site!