I will have to find the link, but last night I was digging around in
their
technical archives and I found a statement to the effect:"All domestic
AM BCB transmitters shall use a 75Us preemphaisis." I was looking
for the maximum analog BW a AM/MW station could use."

In the good old days class A stations could go with, I think up to
15KHz BW. I didn't feel like going to my parents and digging
through the 1955~1970 Popular Electroncs that had an article
on this issue.

I am trying to decide if I want to add a ~10KHz ceramic filter to
my outboard detector.
My fitler line up lloks like it will be:
500HZ crystal filter
2.1KHz crystal filter
3.8KHZ ceramic filter
5KHz ceramic filter
8 or 10KHz ceramic filter
(15KHz crystal filter for FM only!).
The FM will be designed and added later.

The audio will have 2 tilt tone control sections,
similar but with different pivot points. The first
centered at 700, the 2nd at ~1.4KHz. I hope to
decide if I can use one fitler with an ocatave
function, or if 2 fitlers in series will be better.
I would like to keep this simple enough for
someone other then me to use.

I am leaving the original audio chain in the R2000s
intact so that at there very least my wife will able to
use the "listening post".

A friend bought some "exotic" eletronic stuff from a
local engineering firm that went out of business.
Amoung the items were several NEDSP DSP
modules. See:
http://www.bhinstrumentation.co.uk/html/nedsp1061.html
I am trying to trade him out of at least one.
They are tiny, powerfull and don't mangle the audio
"too" much.

My "simple" outboard detector is undergoing
"mission creep".

Terry