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Design for Sound Operated Light Circuit

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Maddy

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Aug 28, 2008, 11:03:34 PM8/28/08
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I am learning morse code. There are software available which convert
any text into morse and give the output to the headphone jack. I was
wondering if this sound output at the headphone/speaker jack can be
used to power a LED or incandescent bulb? Would be thankful if anyone
can suggest a solution.
Thanks
Nitin

JeffM

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Aug 28, 2008, 11:42:24 PM8/28/08
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Maddy wrote:
>I am learning morse code.
>There are software available which convert any text into morse
>and give the output to the headphone jack.
>
http://www.google.com/search?q=cache:B1ftRwdcHhMJ:morsecode.scphillips.com+can-play-*-*-*-*-as-sound+FAQ+*-very-quick+FAQ+FAQ+FAQ+*-runs-on-your-computer-*+*-could-be-slow-if-you-*-*-listen-*-*-*+full-control-*-*.*-*-*-*&strip=1

>I was wondering if this sound output at the headphone/speaker jack
>can be used to power a LED or incandescent bulb?
>

You could use a seperate/additional amplifier.

Frank Buss

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Aug 29, 2008, 12:03:39 AM8/29/08
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Maddy wrote:

You can use your hi-fi system: Use one speaker output for a speaker, if you
want to hear it and connect a 220 ohm resistor and a LED in series to the
other output. Adjust balance and loudness that you can hear something in
the desired loudness and see the LED light, if there is a signal.

A incandescent bulb is not a good idea, because turning it on and off
often, will wear away it fast.

--
Frank Buss, f...@frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de

Jan Panteltje

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Aug 29, 2008, 6:25:02 AM8/29/08
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On a sunny day (Thu, 28 Aug 2008 20:03:34 -0700 (PDT)) it happened Maddy
<mnit...@gmail.com> wrote in
<d5fe71c3-2f99-449a...@a18g2000pra.googlegroups.com>:

+ 9V + 9V
| a |
LED R3
| k ----|
C1 + c | c
audio line level ----|||-----------b NPN |--b NPN
| | e Q1 | e Q2
/// R1 | | |
| R2 | ///
| | |
| /// |
|_____________________|

R1 22k
R2 82 Ohm
R3 2k2
C1 10uF / 3V
Q1, Q2 transistors: almost any NPN si, for example BC548, BC109, etc.

This can be run from a 9 V battery.
It is in fact a very sensitive AC detector.

Optinally one can connect a capacitor from the collector of Q1 to ground.

legg

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Aug 29, 2008, 10:40:52 AM8/29/08
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On Thu, 28 Aug 2008 20:03:34 -0700 (PDT), Maddy <mnit...@gmail.com>
wrote:

I think you will find that Morse is more easily/quickly comprehended
audibly (or in mechanically/electrically written text) than visibly.
In situations where only visible communication is possible, reliable
Morse transmission speed may be reduced to as much as 1/3 that of
other methods. It's also visually exhausting for longer messages -
wearing out the eye's point-perception capacity, quite rapidly.

RL

JeffM

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Aug 29, 2008, 1:43:58 PM8/29/08
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>Maddy (actually, Nitin) wrote:
>>I am learning morse code[...]
>wondering if[...]the headphone/speaker jack

>>can be used to power a LED or incandescent bulb?
>>
Jan Panteltje wrote:
>
> + 9V + 9V
> | a |
> LED R3
> | k ----|
> C1 + c | c
> audio line level ----|||-----------b NPN |--b NPN
> | | e Q1 | e Q2
> /// R1 | | |
> | R2 | ///
> | | |
> | /// |
> |_____________________|
>
While I applaud your effort, my intuition is
1) The OP doesn't know which end of a soldering iron to hold.
1a) He should be posting ONLY to sci.electronics.basics.

2) As he is MULTI-POSTING
news:265128d1-5d07-48db...@l33g2000pri.googlegroups.com
from Google, he is quite clueless
and will see *this* blob (in a proportional font)
http://groups.google.com/group/sci.electronics.design/msg/e37e03faaf5e6b59
and not know what to do with it.

3) Even if he knew how to get to a monospaced version, like
http://groups.google.com/group/sci.electronics.design/msg/e37e03faaf5e6b59?dmode=source
your ASCII technique will likely leave him baffled
(even if you didn't leave out the characters where junctions are
supposed to be).

Frank's answer (and mine) leaning toward COTS stuff
seems more apt.
Even Bill Bowden's response in the s.e.b thread
(to use a step-up transformer) seems over the OP's head.

That's what the evidence says to me. Of course, I could be wrong.

Rich Grise

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Aug 29, 2008, 2:10:48 PM8/29/08
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On Fri, 29 Aug 2008 10:43:58 -0700, JeffM wrote:
>
> That's what the evidence says to me. Of course, I could be wrong.

FWIW, you're one of about two total google posters I've ever seen come
back to read responses. I think they expect the answers to show up under
their pillow or something. ;-)

Thanks,
Rich

Jan Panteltje

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Aug 29, 2008, 2:15:08 PM8/29/08
to
On a sunny day (Fri, 29 Aug 2008 10:43:58 -0700 (PDT)) it happened JeffM
<jef...@email.com> wrote in
<b77ff329-2e95-4c6f...@j22g2000hsf.googlegroups.com>:

>>Maddy (actually, Nitin) wrote:
>>>I am learning morse code[...]
>>wondering if[...]the headphone/speaker jack
>>>can be used to power a LED or incandescent bulb?
>>>
>Jan Panteltje wrote:
>>
>> + 9V + 9V
>> | a |
>> LED R3
>> | k ----|
>> C1 + c | c
>> audio line level ----|||-----------b NPN |--b NPN
>> | | e Q1 | e Q2
>> /// R1 | | |
>> | R2 | ///
>> | | |
>> | /// |
>> |_____________________|
>>

>While I applaud your effort, my intuition is
>1) The OP doesn't know which end of a soldering iron to hold.
>1a) He should be posting ONLY to sci.electronics.basics.

<snip long story>

>That's what the evidence says to me. Of course, I could be wrong.

Sure, just for fun, here is the ltspice version
ftp://panteltje.com/pub/ac_detector_1.gif

You will see about 11mA LED current for 1V input @ 1000Hz.
The LED brightness can be set by the volume control.
As the pulses are 1000Hz, that seems like constant 'on' during key presses.

Fun for me to play , if it educates anyone, great.
He posted to the right group with s.e.d.

JeffM

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Aug 29, 2008, 2:33:46 PM8/29/08
to
>JeffM wrote:
>>[...]That's what the evidence says to me. Of course, I could be wrong.

>>
Rich Grise wrote:
>FWIW, you're one of about two total google posters I've ever seen
>come back to read responses. I think they expect the answers
>to show up under their pillow or something. ;-)

Nah. I won't argue with the general sentiment,
but your arithmetic is off.
Last time he gave a count, JT had 65 of us whitelisted.

Message has been deleted

GregS

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Aug 29, 2008, 8:36:00 AM8/29/08
to

I learned the Morse long ago, but I really don't think I could easily convert
light to letter very easily. One problem for me would be looking at the light and
looking at my sheet. I know it would be a huge problem watching several sources
mixed together.

greg

Maddy

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Aug 30, 2008, 2:44:36 PM8/30/08
to
Thanks a lot for the great response. Especially Jan for the circuit.
As deduced from the evidence, I am a newbie. Dont have much practice
but do surely know which end of the soldering iron to hold. Need the
info to help somebody else implement it. However, didnt quite
understand all the text symbols on the circuit. However, thanks for
it, I will work it out.
Thanks again,
Nitin

LVMarc

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Sep 15, 2008, 5:34:57 PM9/15/08
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This can be one and made into a cool product for hearing impaired
telegraph instruction!

Marc

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