Re: Filter problem

On Sun, 15 Jun 2025 00:57:56 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

john larkin <jl@glen--canyon.com> wrote:

On Sat, 14 Jun 2025 12:52:49 -0000 (UTC), Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:
 

Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:

john larkin <jl@glen--canyon.com> wrote:
 
[...]
 
 

 
This is the classic reference:
 
https://www.amazon.com/s?i=garden&srs=12653393011&bbn=1063498&rh=n%3A10553
98%2Cn%3A284507

 
Amazon won't let me see it because I am not in the USA.  In any case,
won't buy anything from Amazon   Do you have another reference to the
book (I presume it is a book)?
 

 
From the description, I expect John means Williams & Taylor,
<https://archive.org/details/ElectronicFilterDesignHandbook4thEd/page/n2/mode/1up>
or Zverev
<https://www.amazon.com/Handbook-Filter-Synthesis-Anatol-Zverev/dp/0471749427>.
Zverev is my personal fave?I?ve used it occasionally for over 40 years, but
that?s probably a minority taste.
 
Cheers
 
Phil Hobbs

 
Yes, Williams.
 
Does Zverev have tables of filter values? I generally nab a table from
Williams, denormalize and maybe transform it with my program, then
Spice it with part values that I can get, or preferably already have.
 
 

>
Yes. Zverev was a pioneer—the tables were generated directly by a computer,
including the typesetting, which was pretty rad for 1968.
>
He also has really good plots, as well as a unique design, the equiripple
delay filter. That one maintains flat group delay well into the stopband,
unlike Bessels and suchlike.
>
Cheers
>
Phil Hobbs

For my board full of DDS clock generators, I need a new filter form,
the Realibad filter.  As in, say, 6 dB passband ripple.