555 circuit question
688...@mcimail.com
Is is possible to use the 3 pin output of a 555 monostable circuit as the
5v 8 pin input of another 555 astable circuit (e.g., the first 555 is triggered
by a pulse on pin 2, the output on pin 3 goes for, say, 3 secs--therefore,
the second 555 has power for 3 seconds, and will sound its 440hz tone
for three seconds.)
I'm trying to get a predetermined tone and tone length off a short pulse. Is
there a better way to do this?
Drew Oliver
Alan R. Winstanley
In article <4p6pvp$r...@dub-news-svc-6.compuserve.com>,
688...@mcimail.com writes
If you want to build a tone burst generator, with one 555 acting as a 3
second timer to drive another one, acting as an audio oscillator, then a
neater way may be to use a twin timer (556).
Output of first 556 (monostable) timer (pin 5) goes to the reset pin
(pin 10) of the 2nd timer, the astable tone generator.
When the monostable is timing (trigger at pin 6), pin 5 goes high for 3
seconds and enables the oscillator. When it times out after 3 seconds,
pin 5 goes low and resets the audio tone.
You *can* also use separate 555's, both sharing the same power rail but
a 556 is more convenient. Your way is also OK but maybe not quite as
neat.
+alan-
--
Alan Winstanley email: al...@epemag.demon.co.uk Views are my own.
- Everyday Practical Electronics Magazine - In our 25th year!
Wimborne, Dorset, BH21 1PF, United Kingdom
Richard Torrens
>
> Is is possible to use the 3 pin output of a 555 monostable circuit as the
> 5v 8 pin input of another 555 astable circuit (e.g., the first 555 is
> triggered
> by a pulse on pin 2, the output on pin 3 goes for, say, 3 secs--therefore,
> the second 555 has power for 3 seconds, and will sound its 440hz tone
> for three seconds.)
>
> I'm trying to get a predetermined tone and tone length off a short pulse. Is
> there a better way to do this?
>
Try the attached GIF: it is a two tone siren oscillator which may be what you
want. The third section is a speaker driver and can be omitted if not required.
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--
/| Richard Torrens - 4...@argonet.co.uk
/ |
/ | 4 Q D
/ | | We manufacture
/ /| | MOSFET controllers for battery operated motors
/ / | | See us on http://www.argonet.co.uk/users/4qd
/_/__| |____ our www site contains FAQ sheet on motors & controllers
/_____ ____\ and a selection of interesting circuit diagrams
/ _ \| | _ \
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\__\_\ |____/ We use an Acorn RISC-PC 32 bit RISC computer
un...@iap.net.au
<688...@mcimail.com> wrote:
>Is is possible to use the 3 pin output of a 555 monostable circuit as the
>5v 8 pin input of another 555 astable circuit (e.g., the first 555 is triggered
>by a pulse on pin 2, the output on pin 3 goes for, say, 3 secs--therefore,
>the second 555 has power for 3 seconds, and will sound its 440hz tone
>for three seconds.)
>I'm trying to get a predetermined tone and tone length off a short pulse. Is
>there a better way to do this?
>Drew Oliver
For about another 20c, use the output of pin 3 of the first
one to the base of an NPN, (thru a nominal resistor, of
course, like say 1k) this transistor to switch your 5v (or
whatever) to the pin 8 B+ of the next 555.
Uncle Brian VK6BQN
Richard G.
In article GR4DSEAy...@epemag.demon.co.uk,
"Alan R. Winstanley" <al...@epemag.demon.co.uk> said:
>
>In article <4p6pvp$r...@dub-news-svc-6.compuserve.com>,
>688...@mcimail.com writes
>>
>>5v 8 pin input of another 555 astable circuit (e.g., the first 555 is
>triggered
>>by a pulse on pin 2, the output on pin 3 goes for, say, 3 secs--therefore,
>>the second 555 has power for 3 seconds, and will sound its 440hz tone
>>for three seconds.)
>>
>>I'm trying to get a predetermined tone and tone length off a short pulse. Is
>>there a better way to do this?
>>
>
>second timer to drive another one, acting as an audio oscillator, then a
>neater way may be to use a twin timer (556).
>
>Output of first 556 (monostable) timer (pin 5) goes to the reset pin
>(pin 10) of the 2nd timer, the astable tone generator.
>
The 555 will operate just fine as you stated. There is, of course a maximum source to consider, but if the oscillator is seperately amplified, you will be okay no matter what.
Richard and/or Clay
Un...@iap.net.au wrote:
>
> <688...@mcimail.com> wrote:
>
> >Is is possible to use the 3 pin output of a 555 monostable circuit as the
> >5v 8 pin input of another 555 astable circuit (e.g., the first 555 is triggered
> >by a pulse on pin 2, the output on pin 3 goes for, say, 3 secs--therefore,
> >the second 555 has power for 3 seconds, and will sound its 440hz tone
> >for three seconds.)
>
> >I'm trying to get a predetermined tone and tone length off a short pulse. Is
> >there a better way to do this?
>
>
> For about another 20c, use the output of pin 3 of the first
> one to the base of an NPN, (thru a nominal resistor, of
> course, like say 1k) this transistor to switch your 5v (or
> whatever) to the pin 8 B+ of the next 555.
>
> Uncle Brian VK6BQN
subsequent stage would sink more than that unless it was sourcing as
much, but that is why you use the amplifier on the oscillator stage.
--
"Nobody ever went broke underestimating
the intelligence of the American public."
Richard G. Mainar Digi...@serv.net
Sam Goldwasser
> For about another 20c, use the output of pin 3 of the first
> one to the base of an NPN, (thru a nominal resistor, of
> course, like say 1k) this transistor to switch your 5v (or
> whatever) to the pin 8 B+ of the next 555.
Why switch power at all when you can probably just use the reset input
to enable the tone generator?
--- sam
> Uncle Brian VK6BQN
.
Richard and/or Clay
consideration here.