Re: Bandpass filter with adjustable Q

On Fri, 22 Jul 2005 11:41:48 -0700, The Phantom <phantom@xxxxxxx>
wrote:

>There has been interest in the past concerning filters with the property that some
>parameter of the filter can be adjusted (with, say, a potentiometer) without peturbing
>other parameters. The latest issue of Electronic Design magazine has such a design in the
>Ideas for Design section.
>
>http://www.elecdesign.com/Articles/ArticleID/10684/10684.html
>
>I'm not sure but what I may have seen this one before, but I thought I'd call it to the
>attention of the group.

The "Twin-T" approach is the pitts. For how to do it right see all
the gyrator-based filters on the S.E.D/Schematics page of my website.
These feature independent adjustment of bandwidth and center
frequency.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
.

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