newbie + NE555 = :-(
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Posts: 46,084
hello all!
first off id just like to say that it has been a pleasure being a member of
this list-serve. Great community! Anyways, for the life of me, i simply CANNOT
get a 555 timer to oscillate. I've tried several different configurations
from several sites online, and have even built the circuit in the "what is a
microcontroller" book. I have tried 5 different chips just to see if maybe i got
a couple bad ones. Could any of you pros give me some pointers on how to get
this sucker working? I'm four weeks into a HUGE project and it has come to a
screeching halt because of my 555 impotence. Here is some basic info on my
setup: I'm using a 5-volt regulator, a TI NE555P (42CL2CM), a 10 mf elect. cap., a
15K & a 1K resistor. Oh, i should probably also mention that I am shooting
for an astable 10Hz vibrator. I know its hard to troubleshoot a circuit when its
not in front of you, so let's use the one in figure 5.2, pg. 74 in the "what
is a microcontroller" book from parallax. how could one screw a circuit like
that up? what are all the possible souces of failure? ALso, why does it seem
like every site about 555's have a diffrent configuration? Please keep in mind
that I am not a EE (although I am pretty handy with a soldering iron). In the
event that i never figure this out, anyone have any ideas on how to build a
10 Hz oscillator using a different technique? HELP PLEASE!
thanks in advance,
joe
P.S. i know that the RC configuration i mentioned above wont result in 10 Hz
- that's the configuration they use in the book i mentioned.
[noparse][[/noparse]Non-text portions of this message have been removed]
first off id just like to say that it has been a pleasure being a member of
this list-serve. Great community! Anyways, for the life of me, i simply CANNOT
get a 555 timer to oscillate. I've tried several different configurations
from several sites online, and have even built the circuit in the "what is a
microcontroller" book. I have tried 5 different chips just to see if maybe i got
a couple bad ones. Could any of you pros give me some pointers on how to get
this sucker working? I'm four weeks into a HUGE project and it has come to a
screeching halt because of my 555 impotence. Here is some basic info on my
setup: I'm using a 5-volt regulator, a TI NE555P (42CL2CM), a 10 mf elect. cap., a
15K & a 1K resistor. Oh, i should probably also mention that I am shooting
for an astable 10Hz vibrator. I know its hard to troubleshoot a circuit when its
not in front of you, so let's use the one in figure 5.2, pg. 74 in the "what
is a microcontroller" book from parallax. how could one screw a circuit like
that up? what are all the possible souces of failure? ALso, why does it seem
like every site about 555's have a diffrent configuration? Please keep in mind
that I am not a EE (although I am pretty handy with a soldering iron). In the
event that i never figure this out, anyone have any ideas on how to build a
10 Hz oscillator using a different technique? HELP PLEASE!
thanks in advance,
joe
P.S. i know that the RC configuration i mentioned above wont result in 10 Hz
- that's the configuration they use in the book i mentioned.
[noparse][[/noparse]Non-text portions of this message have been removed]
Comments
How do you know it is not working? Are you using a scope, dvom, led
Indicator or what?
Ken,
============
hello all!
first off id just like to say that it has been a pleasure being a member of
this list-serve. Great community! Anyways, for the life of me, i simply
CANNOT
get a 555 timer to oscillate. I've tried several different configurations
from several sites online, and have even built the circuit in the "what is a
microcontroller" book. I have tried 5 different chips just to see if maybe
i got
a couple bad ones. Could any of you pros give me some pointers on how to get
this sucker working? I'm four weeks into a HUGE project and it has come to a
screeching halt because of my 555 impotence. Here is some basic info on my
setup: I'm using a 5-volt regulator, a TI NE555P (42CL2CM), a 10 mf elect.
cap., a
15K & a 1K resistor. Oh, i should probably also mention that I am shooting
for an astable 10Hz vibrator. I know its hard to troubleshoot a circuit when
its
not in front of you, so let's use the one in figure 5.2, pg. 74 in the "what
is a microcontroller" book from parallax. how could one screw a circuit like
that up? what are all the possible souces of failure? ALso, why does it
seem
like every site about 555's have a diffrent configuration? Please keep in
mind
that I am not a EE (although I am pretty handy with a soldering iron). In
the
event that i never figure this out, anyone have any ideas on how to build a
10 Hz oscillator using a different technique? HELP PLEASE!
thanks in advance,
joe
[noparse][[/noparse]Non-text portions of this message have been removed]
Just a few suggestions: Check Vcc, that is, make sure that the +5V
regulator is actually working. Next, check your wiring setup. I have used 555's and
556's for many years and found them to be pretty predictable. If the setup
is wrong, and you keep plugging 555's into it, it still won't work.
Since you're not an EE, you might get some help from Engineer's
Mini-Notebook series published by Forrest M. Mims III, and sold through Radio Shack. No.
62-5010 deals specifically with 555 Timer Circuits.
Good luck. Let me know if this helps.
Mike
[noparse][[/noparse]Non-text portions of this message have been removed]
10 Hz is slow. To get that, I might use a
555 at a reasonable frequency driving a divider
chain.
Of course, I've done very little with 555's --
I usually want way more frequency accuracy than
they will produce.
--- In basicstamps@yahoogroups.com, joecasa@a... wrote:
> hello all!
> first off id just like to say that it has been a pleasure being a
member of
> this list-serve. Great community! Anyways, for the life of me, i
simply CANNOT
> get a 555 timer to oscillate. I've tried several different
configurations
> from several sites online, and have even built the circuit in
the "what is a
> microcontroller" book. I have tried 5 different chips just to see
if maybe i got
> a couple bad ones. Could any of you pros give me some pointers on
how to get
> this sucker working? I'm four weeks into a HUGE project and it has
come to a
> screeching halt because of my 555 impotence. Here is some basic
info on my
> setup: I'm using a 5-volt regulator, a TI NE555P (42CL2CM), a 10 mf
elect. cap., a
> 15K & a 1K resistor. Oh, i should probably also mention that I am
shooting
> for an astable 10Hz vibrator. I know its hard to troubleshoot a
circuit when its
> not in front of you, so let's use the one in figure 5.2, pg. 74 in
the "what
> is a microcontroller" book from parallax. how could one screw a
circuit like
> that up? what are all the possible souces of failure? ALso, why
does it seem
> like every site about 555's have a diffrent configuration? Please
keep in mind
> that I am not a EE (although I am pretty handy with a soldering
iron). In the
> event that i never figure this out, anyone have any ideas on how to
build a
> 10 Hz oscillator using a different technique? HELP PLEASE!
>
> thanks in advance,
> joe
>
> P.S. i know that the RC configuration i mentioned above wont result
in 10 Hz
> - that's the configuration they use in the book i mentioned.
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
post a copy in the files section.
Make sure you have 2 and 6 tied together so you don't have a mono-
stable or single shot timer.
And make sure the cap is uF and not nF MicroF is uF and nano-F is
nF.
Dave
--- In basicstamps@yahoogroups.com, joecasa@a... wrote:
> hello all!
> first off id just like to say that it has been a pleasure being a
member of
> this list-serve. Great community! Anyways, for the life of me, i
simply CANNOT
> get a 555 timer to oscillate. I've tried several different
configurations
> from several sites online, and have even built the circuit in
the "what is a
> microcontroller" book. I have tried 5 different chips just to see
if maybe i got
> a couple bad ones. Could any of you pros give me some pointers on
how to get
> this sucker working? I'm four weeks into a HUGE project and it has
come to a
> screeching halt because of my 555 impotence. Here is some basic
info on my
> setup: I'm using a 5-volt regulator, a TI NE555P (42CL2CM), a 10 mf
elect. cap., a
> 15K & a 1K resistor. Oh, i should probably also mention that I am
shooting
> for an astable 10Hz vibrator. I know its hard to troubleshoot a
circuit when its
> not in front of you, so let's use the one in figure 5.2, pg. 74 in
the "what
> is a microcontroller" book from parallax. how could one screw a
circuit like
> that up? what are all the possible souces of failure? ALso, why
does it seem
> like every site about 555's have a diffrent configuration? Please
keep in mind
> that I am not a EE (although I am pretty handy with a soldering
iron). In the
> event that i never figure this out, anyone have any ideas on how to
build a
> 10 Hz oscillator using a different technique? HELP PLEASE!
>
> thanks in advance,
> joe
>
> P.S. i know that the RC configuration i mentioned above wont result
in 10 Hz
> - that's the configuration they use in the book i mentioned.
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
> 10 Hz is slow. To get that, I might use a
> 555 at a reasonable frequency driving a divider
> chain.
About 10 years ago my employer at the time wanted me to generate a 1/4
second pulse about every 30 seconds to "bug" an automotive fuel injection
system for training classes. I would have preferred to use a Stamp to vary
the time between each "glitch", but they were making a number of them and
there wasn't enough in the budget. Ended up using a 555, but getting that
duty cycle was a little tricky. CMOS 555s can do much longer delays/lower
frequencies.
Joe,
There is a photo of a 555 connected on a breadboard for low frequency
operation at:
http://www.glitchbuster.com/astable555.htm
You can see most of the connections in the picture. Perhaps it would help
with your troubleshooting.
-Randy
www.glitchbuster.com