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AFEX54
Joined: Apr 10, 2015 Posts: 3 Location: Ireland
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Posted: Fri Apr 10, 2015 10:22 am Post subject:
Modifying this oscillator to change frequency range? |
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http://www.instructables.com/id/THE-SIMPLEST-FUNCTION-GENERATOR-BUILT-ON-A-BREADBO/
I was drawn to this oscillator because it uses an LM324 which i happened to have lying around and it also has 3 waveforms, including a sine which i needed.
however its frequency range is not ideal, it goes well above the range of human hearing which is useless to me and only as low as 500hz when id prefer it more near 1HZ or so.*
i'm very much a noob but i know that this is possible because the MFOS Alien Screamer uses the same op amp and can achieve these kind of low frequencies
Thanks for your time !
*im basing this fact on a persons comment from that instructable: 'hey could you tell me what is the range of frequency it works? Actually I don't know if I'm right, according to the equation it should be from 500Hz to aprox 5MHz.' |
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bubzy
Joined: Oct 27, 2010 Posts: 594 Location: United Kingdom
Audio files: 64
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Posted: Fri Apr 10, 2015 4:07 pm Post subject:
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change the pot for a higher value (1m for example)
you can also play with the value of C1 to try and make LFO etc
edit:
_________________ _Richard_ |
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AFEX54
Joined: Apr 10, 2015 Posts: 3 Location: Ireland
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Posted: Fri Apr 10, 2015 5:43 pm Post subject:
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bubzy wrote: | change the pot for a higher value (1m for example)
you can also play with the value of C1 to try and make LFO etc
edit:
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wow its that easy? thanks!
im a little confused about playing with C1 though,
how is this LFO different from the low frequency oscillation achieved by just using the higher value pot? IE what does the cap do? |
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bubzy
Joined: Oct 27, 2010 Posts: 594 Location: United Kingdom
Audio files: 64
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Posted: Sat Apr 11, 2015 2:00 am Post subject:
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im not a great theorist, i just poke and play
afaik :
the cap is the "timing" cap, and the value will affect how long there is between "on" and "off"
the pot will affect how long it takes the cap to charge.
but as usual i could be wrong
/diy /rich
also visit the chat room, theres some helpful people in there, also they have jovianpyx. _________________ _Richard_ |
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AFEX54
Joined: Apr 10, 2015 Posts: 3 Location: Ireland
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Posted: Sat Apr 11, 2015 10:54 am Post subject:
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bubzy wrote: | im not a great theorist, i just poke and play
afaik :
the cap is the "timing" cap, and the value will affect how long there is between "on" and "off"
the pot will affect how long it takes the cap to charge.
but as usual i could be wrong
/diy /rich
also visit the chat room, theres some helpful people in there, also they have jovianpyx. |
Thanks, I think i will just build this on a breadboard before i start pestering you with more questions, im sure most of them will answer themselves once i do |
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