volume control

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what in
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volume control

Post by what in »

i was wondering if anybody knows of a way to set up a amp sound system that will get progressively louder with a hi pin input then reset and go off when it goes low. i plan to use it in conjuction with a motion detector. i don't realy want to use a microcontroller, i would perfer to get away with a circuit if possible. Any ideas would be welcome.
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Chris Smith
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Re: volume control

Post by Chris Smith »

Digital pots
Bernius1
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Re: volume control

Post by Bernius1 »

Or a 4066 series bi-lateral switch with a pot in series.
Can't we end all posts with a comical quip?
chessman
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Re: volume control

Post by chessman »

Hmm....like I've said, I'm no genius, or even an EE....but i'll throw my idea out there.<p>555 timer gives clocks to a 4040 which has a logic chain to control the digital pot...that way each clock of the 555 would be progressivly louder.....you can use a couple op-amps to buffer an RCA input and RCA output so the signal to the amp would depend on the value of the digital pot.
Bernius1
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Re: volume control

Post by Bernius1 »

The 4066 bilateral switch is 4 electronic SPST 'toggle' switches. I would;
* output motion sensor to 555 & a BCD 4-bit counter
* send the 4-bit outs to the controls of the 4066
* use the 4066 with 4 varied resistors, and put them in the feedback ( Rf ) of your output op-amp.
( this adjusts gain )
* use a BCD counter with reset, and start the 555 low, so after the motion stops, the 555 will reset the counter ( after a time you set ). Then all resitors are reset.
Adv; this is off-the-cuff, and will need refinement to lower quescient current draw.
? Anyone care to return the volley ?
Can't we end all posts with a comical quip?
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