Graeme Zimmer wrote:

Hi Bob,

> But the intended thrust of this email is to ask about if anyone can find
> a reference to a BESSEL BANDPASS filter.

"Electronic Filter Design Handbook" by Williams and Taylor
has a section on "Capacitive Coupled Resonant" bandpass filters.
(These are the kind where a number of parallel tuned circuits are coupled
together via capacitors)

The book offers a table for Bessel parameters.

It does a design for "constant delay over passband" bandpass using the
Bessel tables...

Let me know if you could use a photocopy of a few pages.....

......................... Zim ............. VK3GJZ

My first reply was direct to Zim, but I should also acknowledge it to
reflector reader:

I would like a copy, thanks for the offer Zim.

I'm intending to build an active filter equivalent, where each stage is
practically independent of others, which is different to the mutually
coupled passive filter, but the design info would be interesting in its
own right.

73, Bob