Maker Pro
Maker Pro

problems with 555 timer.

Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Thanks for your help,
-sam
 
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Thanks for your help,
-sam


Post a link to your schematic, if possible (on a personal website).

Try building this circuit to test your 555 (maybe it's burned out?)
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

Michael
 
A

Anthony Fremont

Jan 1, 1970
0
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

Then there is something wrong with the 555. As long as you have
correctly identified pin numbers 1 and 8, then applying power should not
result in a large current draw.

Check here:
http://www.uoguelph.ca/~antoon/gadgets/555/555.html
But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Try another 555.
 
D

Donald

Jan 1, 1970
0
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Thanks for your help,
-sam

Please send us your schematic.

Not the web site schematic, the schematic of the thing _you_ wired.

PS: maybe your in the wrong hobby.
 
M

Mark Fortune

Jan 1, 1970
0
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Thanks for your help,
-sam

Very little information to go on, but i'll give it a shot..

It does sound like something is shorting out. what schematic are you
working from exactly? also make sure you have the capacitors connected
the right way around as specified in the schematics.
If you do have a picture of how you've wired it all together too, and
can post it on the web somewhere that would be very helpful.

What light are you using (the one you want to blink) as its possible
it's drawing too much current. A 1KOhm resistor in series with an LED on
the output draws very little current and is a good indicator of wether
it's working.

Is the chip the right way around, and also is your understanding of the
pin layout correct, it should be as follows:
_____
[1]| u |[8] (+)
[2]| |[7]
output==[3]| |[6]
(-)=[4]|_____|[5]

there's a very basic circuit on my site for a 555 astable timer,
although you've probably come across the design before (it's quite
popular as a beginners model)

http://www.fortrex.co.uk/circuits/555_astable.shtml
</blatent advertising>

Although the schematic states 12V, the circuit should operate at any
voltage in the range +5v to +15v

a good starting point is to use a 220uF capacitor for C1 and R1 and R2
as a 2KOhm resistor for R1 and a 5KOhm resistor for R2, that should give
you an on time of about 1 second and an off time of about 0.7 seconds.

If all else fails, your 555 chip could be dead. do you have a spare to
try it out with?

Regards,
Mark
 
T

Tim Wescott

Jan 1, 1970
0
Donald said:
Please send us your schematic.

Not the web site schematic, the schematic of the thing _you_ wired.

PS: maybe your in the wrong hobby.

Naa, if your response to seemingly insurmountable, unexplainable
problems is to keep trying then you're definitely cut out for electronics.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Posting from Google? See http://cfaj.freeshell.org/google/

"Applied Control Theory for Embedded Systems" came out in April.
See details at http://www.wescottdesign.com/actfes/actfes.html
 
M

Mark Fortune

Jan 1, 1970
0
Mark Fortune wrote:

EEK!
I put the (-) terminal in the wrong place. Should be:
(-) [1]| u |[8] (+)
[2]| |[7]
output==[3]| |[6]
[4]|_____|[5]

also notice the little notch at the top of the chip

My bad!

Mark
 
This is the schematic... the basic astable 555 that I know and hate.
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

Maybe I shorted it out somehow, today I'm going to buy another 555 and
try it again.

For now.. can you guys tell me if this should happen?

(-) 1 | u | 8 LED (+)

negative to pin 1, pin 8 to LED to positive. Nothing else is connected
anywhere.

The LED turns on very bright... is this proof my 555 is toast?

Thanks for the help... if I have more trouble I'll post pics.

Thanks,
-sam
 
L

Luhan

Jan 1, 1970
0
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.

I have a 9 volt battery, the proper resistors, capacitors, etc. It's
driving me nuts.

Generally, the problem is all the schematics call for pin 1 to be
connected to ground, and pin 8 connected to V+. I don't know exactly
what this means, so I connect pin 1 to the negative current, and pin 8
to positive current. When I do this, I feel like it's shorting out or
something, because nothing else on the breadboard (like an LED in
parralel to the 555 circuitry) will work, and the battery starts to get
really hot.

But besides that, I do everything exactly as in the schematics, and
everytime nothing works.

I'm getting really frustrated at this thing because I set up everything
exactly as in the schematics, plug it in, and nothing happens. I would
really appreciate your help, as I've pretty much exausted every 555
timer website on the net for help.

Thanks for your help,
-sam

Since you probably cannot read a schematic, could you post a link to a
close up photo of what you have built?

Luhan
 
M

Mark Fortune

Jan 1, 1970
0
This is the schematic... the basic astable 555 that I know and hate.
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

Maybe I shorted it out somehow, today I'm going to buy another 555 and
try it again.

For now.. can you guys tell me if this should happen?

(-) 1 | u | 8 LED (+)

negative to pin 1, pin 8 to LED to positive. Nothing else is connected
anywhere.

Why are you connecting the LED to pin 8 (+)?

pin 8 should be the +v source for the 555 and should be connected direct
to the +9v supply. If you put the LED where you said you have then the
555 is probably not getting enough power to start up, and if you've not
got a resistor in series with the LED chances are the LED should have
burnt out by now.
 
J

John Woodgate

Jan 1, 1970
0
dated said:
Post a link to your schematic, if possible (on a personal website).

Try building this circuit to test your 555 (maybe it's burned out?)
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

It's a very good site BUT it's far too comprehensive for a beginner.

Look at Figure 5, that is the thing to build. You can study all the rest
AFTER you've got Figure 5 to work.

Yes, your 555 may be dead. They are difficult to kill, but it can be
done.
 
Mark, this wasn't part of my schematic... I was wondering if this
proves that my 555 is broken or not.

I am in fact new to electronics, but I don't expect the below schematic
to magically cause an LED to blink.

-sam
 
M

Michael Black

Jan 1, 1970
0
Hello, everyone. This is my first electronics project, and all I'm
trying to do is get a light to blink. I looked up schematics on about
10 different websites, all which have failed.
The proper newsgroup for questions like this is sci.electronics.basics

Besides, if you are asking about timers here, the proper solution is
generally a microprocessor.

Michael
 
J

John Woodgate

Jan 1, 1970
0
dated said:
Mark, this wasn't part of my schematic... I was wondering if this
proves that my 555 is broken or not.

Probably, but without knowing how you have connected the other pins, we
can't be sure.
I am in fact new to electronics, but I don't expect the below schematic
to magically cause an LED to blink.

You are getting some rather abrupt responses, which don't help much.
This is because you are really in the wrong newsgroup. You should be in
sci.electronics.basics

However, now you ARE here, we will try to help. Have you built that
Figure 5 circuit? If so, tell us what happens.
 
J

John Woodgate

Jan 1, 1970
0
dated Mon said:
Besides, if you are asking about timers here, the proper solution is
generally a microprocessor.

Oh, no! Not another one. 555 timer, what, 50 cents all up? Time to first
blink 30 minutes maximum, if you don't goof.

Microprocessor timer 10 cents for the chip, USD100 for the development
system and four weeks to learn to program it.
 
T

Tim Wescott

Jan 1, 1970
0
John said:
Oh, no! Not another one. 555 timer, what, 50 cents all up? Time to first
blink 30 minutes maximum, if you don't goof.

Microprocessor timer 10 cents for the chip, USD100 for the development
system and four weeks to learn to program it.

But then you can make it blink in Morse code!

I use both, but each in it's appropriate spot. If _all_ you need is
blinky, a 555 is the way to go.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Posting from Google? See http://cfaj.freeshell.org/google/

"Applied Control Theory for Embedded Systems" came out in April.
See details at http://www.wescottdesign.com/actfes/actfes.html
 
J

Jonathan Kirwan

Jan 1, 1970
0
Oh, no! Not another one. 555 timer, what, 50 cents all up? Time to first
blink 30 minutes maximum, if you don't goof.

Microprocessor timer 10 cents for the chip, USD100 for the development
system and four weeks to learn to program it.

Not to mention that this "to 555, or not to 555" question may lead to
a life-changing decision for a promising, heroic electronics designer
eventually slipping away into the evils of software programming and
the corrupting influences of its dark minions. ;)

Jon
 
M

Michael A. Terrell

Jan 1, 1970
0
Tim said:
But then you can make it blink in Morse code!

I use both, but each in it's appropriate spot. If _all_ you need is
blinky, a 555 is the way to go.


If you were really good, you could make it flash in Morse code with
some 555s! ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
M

Michael A. Terrell

Jan 1, 1970
0
Jonathan said:
Not to mention that this "to 555, or not to 555" question may lead to
a life-changing decision for a promising, heroic electronics designer
eventually slipping away into the evils of software programming and
the corrupting influences of its dark minions. ;)



You're right! When will people learn that you really do have to add
some bleach when they wash their minions? ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
J

John Fields

Jan 1, 1970
0
Mark, this wasn't part of my schematic... I was wondering if this
proves that my 555 is broken or not.

I am in fact new to electronics, but I don't expect the below schematic
to magically cause an LED to blink.

Please bottom post or in-line post where necessary.
 
Top