[TenTec] Notch Filters and Speech Processing in Orion V2 Code

[Merle Bone]

Bill Tippet wrote:

  Just hours later I received a response
from K4JU Jack Burchfield, CEO of Ten-Tec:
"I understand your problem with the agc and notch and so does
Gary."
<details snipped>
"We have been working on possible solutions and have
not shelved it!  Will keep you in the loop."
...........................................................................................

I have also been communicating with Jack Birchfield of a number of
areas of "performance degradation" and "bugs" in the Orion V2 code,
including the issue of the notch filters being outside the AGC loop - which
causes the notched signals to still pump the AGC and desensitize the receiver.
We have exchanged a number of letters and he recently wrote:

"Notch etc: This is a bit of a problem. We would like to have a "clean-up" filter after all
DSP. The gain and AGC causes some unwanted noise and the clean-up filter removes
this noise. We tried to solve both that and the notch behind the AGC. So far there is not
a clear cut solution and we feel that the filter is more important to more operators. This
does not mean that we will not continue to search for a solution."

I wonder if the "clean-up filter" is required because of the redesign of the Orion DSP modulator/demodulator
from a "filter method design" to a Weaver method design in the V2 code? Maybe someone on the list understands this
change and the need for the clean-up filter - which was not in the Orion V1 code and - as best as I can see - 
is not missed?

I had also reported issues with the Speech Processing performance in the V2 code.
Jack Burchfield also commented:

"The speech processing has been changed and should be posted within a couple of weeks. We
will continue  to communicate and at least let everyone know why we did some of the 
things that are in question."

This certainly is good news. Hopefully we can get some of the Orion V2 issues resolved before the Omni-VII starts
to dominate the use of the DSP programming resources.

Merle - W0EWM