555 timer help

Simeoelite

New Member

• Jul 13, 2016

• #1

Hello guys
I'm in middle of my project presentation, I have build an electronic bird repeller using two 555 timers. The first 555 timer produce the required frequency of 250Hz but the second 555 timer doesn't give any output on the oscilloscope although on the simulation (Using Proteus) everything is okay.
I've attached the picture of my prototype. I really need your help.
Thanks.

 

alec_t

Well-Known Member

Most Helpful Member

• Jul 13, 2016

• #2

Welcome to ETO!
It's difficult to help without a schematic and sharp well-lit pics of both sides of the pcb.

 

AnalogKid

Well-Known Member

Most Helpful Member

• Jul 15, 2016

• #3

Exactly what do you expect us to do with a picture of 40 components? If I send you a picture of my lawn mower, will you tell me why it doesn't run? THINK. This is an electrical engineering forum. We don't even burp without a schematic.

ak

 

absf

Active Member

• Jul 16, 2016

• #4

Show us the proteus schematic or a screen capture of the proteus running on PC that works. May be then you'll get more help from others.

Allen

 

Mosaic

Well-Known Member

• Jul 17, 2016

• #5

Why is an IC socket using an undersized IC BTW?
Is that the correct part?

 

djsfantasi

Member

• Jul 17, 2016

• #6

Mosaic said:

Why is an IC socket using an undersized IC BTW?
Is that the correct part?

Click to expand...

And if it is the correct part, is it inserted correctly? Maybe the empty sockets belong on the other side...

 

dr pepper

Well-Known Member

Most Helpful Member

• Jul 19, 2016

• #7

Do you have a 10nf to ground on pin5?, some chips need it.

 

E

eTech

Well-Known Member

• Jul 20, 2016

• #8

IC's seem to be missing bypass caps..
Hard to tell but one timer seems to have no trace to pin 8 (VCC).