Fwd: Re: [sdiy] VCA controls

[René Schmitz]

I've seen oldskool VU circuits that have a series chain of 
LEDs. Each LED is paralleled by a transistor, the whole 
chain is driven by a constant current source. So there 
should be low supply current (20mA?) needed and probably 
little chance for supply infestation.

Cheers,
 René

At 14:19 10.05.02 -0700, greg montalbano wrote:
>I was wondering the same thing (in slightly less acerbic terms) --
>have some of you come up with ways of including mass LEDs without
>the associated monster current drain?
>
>Inquiring minds want to know...
>
>~GMM
>
>
>
>>From: "Happy Harry" <paia2720 at hotmail.com>
>>
>>Oh YEAH baby...
>>
>>LED VU meter...  use the LM3914 and let the
>>nasty spikey noise get all over your power
>>supply.... AND contribute to global warming
>>at the same time.
>>
>>It will REALLY be good if you use a wallwart
>>supply...
>>
>>Be sure to avoid wimpy "dot mode"  ;^P
>>
>>H^) harry
>>
>>
>>>From: Tim Ressel <madhun2001 at yahoo.com>
>>>To: Dave Magnuson <resfreq at hoohahrecords.com>,   Synth-Diy 
>>><synth-diy at dropmix.xs4all.nl>
>>>Subject: Re: [sdiy] VCA controls
>>>Date: Fri, 10 May 2002 13:26:29 -0700 (PDT)
>>>
>>>Okay, I'm confused: attenuator on the audio input, log
>>>response; attenuator on the cv input, log response.
>>>That seems redundant to me. Input mixer, yeah I can
>>>see that.
>>>
>>>I have room for three pots. Four, if I scrunch things.
>>>So I'm thinking: Init gain (bias on a cv input), +/-1
>>>gain adjust on one cv input, pan between two signal
>>>inputs, and a signal/clip indicator.
>>>Maybe even a led VU meter. Yeah. This thing doesn't
>>>have enough lights...
>>>
>>>--TR
>>>
>>>**************************
>>>Happiness is flashing LEDs
>>>and clicking relays
>>>**************************
>>>
>>>__________________________________________________
>>>Do You Yahoo!?
>>>Yahoo! Shopping - Mother's Day is May 12th!
>>>http://shopping.yahoo.com
>>
>>
>>
>>
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>
>
-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159