TenTec
[Top] [All Lists]

Re: [TenTec] DSP Filter BW (1.366 vs previous)

To: <tentec@contesting.com>
Subject: Re: [TenTec] DSP Filter BW (1.366 vs previous)
From: "Carl Moreschi" <n4py@earthlink.net>
Reply-to: tentec@contesting.com
Date: Fri, 14 Nov 2003 23:44:49 -0000
List-post: <mailto:tentec@contesting.com>
I just did some preliminary measurements and it looks like with 199 taps
selected, the filters are identical to what they were before.  So it appears
we always had 199 taps and now we can soften or widen the filter slope by
selecting less taps.

What I like in this version is for the first time since I received my Orion
last May, my CW sidetone is clear in my headphones.  It was always scratchy
in the headphones before.  And the SSB monitor is now clear sounding in
headphones instread of being distorted.

Carl Moreschi N4PY
Franklinton, NC
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <tentec@contesting.com>
Sent: Friday, November 14, 2003 10:02 PM
Subject: [TenTec] DSP Filter BW (1.366 vs previous)


> Mark Erbaugh wrote:
> For those of you who have upgraded, does this feature allow
> you to sharpen the filters beyond what was in previous releases or were
> previous releases hard coded with 199 taps?
>
>          N4PY previously reported the original DSP filters as:
>
> Filter       6 DB width     60 DB width    Shape Factor
>
> 100            150             440              2.9:1
> 250            240             470              1.95:1
> 500            510             820              1.6:1
> 1000           980            1160              1.2:1
> 1600          1580            1880              1.2:1
> 2400          2360            2500              1.06:1
> 3000          2930            3270              1.12:1
> 4000          3960            4280              1.08:1
>
> http://dayton.akorn.net/pipermail/tentec/2003-May/033783.html
>
>          Carl, how about doing it again for the max and min
> tap settings?  It appears that the previous tap settings may
> have been variable with bandwidth, but some measurements would
> be very helpful.  If any others decide to make this measurement,
> remember to take the roofing filter out of the picture by fixing
> Xtal Filter to 20 kHz.
>
>                                          73,  Bill  W4ZV
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec

_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec

<Prev in Thread] Current Thread [Next in Thread>