[sdiy] rectification/min/max question

[Derek Holzer]

Hi Dave, Ian, the list...

thank you Ian for the references on op-amps. The Wikipedia article and 
the op-amp applications sheet were ones that I came across in my 
research as well. I looked through the Wikipedia page for a couple 
hours, but I'm not much of an engineer when it comes to math, so I ended 
up beating my head against the wall for a while. Still, a good learning 
experience...

Then I went to the breadboard and tried out the circuit that Dave 
suggested, which works quite well. I'm listening to it modulate an LPF 
right now. I did simplify it a bit, removing the second op-amp pair 
which was providing reference voltage and just putting +/- 12V to the 
two ends of the Offset pot. Quite a simple circuit and does what I need 
it to!

thx + best,
d.

Dave Manley wrote:
> Take a look at this, it has adjustable gain and offset:
> 
> http://www.oldcrows.net/~patchell/synthmodulesII/200-1018.pdf
> 
> The circuit could be simplified, as there is a voltage reference for the 
> offset pot you probably don't need.

> Ian Fritz wrote:
>> Some references on general op amp summers
>> 
>> http://en.wikibooks.org/wiki/Circuit_Idea/Simple_Op-amp_Summer_Design
>> http://www.edn.com/index.asp?layout=ednPDF&file_name=/archives/1998/030298/05df_05.pdf 
>> 
>> http://www.phy-astr.gsu.edu/nelson/AN-31.pdf


-- 
derek holzer ::: http://www.umatic.nl ::: http://blog.myspace.com/macumbista
---Oblique Strategy # 192:
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