Roofing filter for CW

[Eric Manning]

I VOTE FOR 250 HZ.

No ringing, I don't think I miss much as I tune around,
and you can narrow it further with the DSP filtering.


eric [ "250 Hz Forever!]  VA7DZ

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[Dave Agsten]

Bill,

I find that both the 200Hz and 500Hz filters work just fine. I decided to save $50 and not buy 8 pole filters. I think the 8 pole hype is somewhat just that. I have a 2nd 500Hz in the second RX.
 
 73,
Dave N8AG


     
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[Bob - W0GI]

I don't think it is hype, as the 8 pole filters have steepers skirts, but in practical terms, do the steeper skirts buy you much? I do know that the 250 has a lot of loss.

I keep hoping I can find a 500 for $50. It would be a nice addition to the 250. :>)



<<<<<<<<<<
I find that both the 200Hz and 500Hz filters work just fine. I decided to save $50 and not buy 8 pole filters. I think the 8 pole hype is somewhat just that. I have a 2nd 500Hz in the second RX.
 
 73,
Dave N8AG >>>>>>>>>>>

[dl4maq]

I agree with Eric; I started with the 1000Hz and the 400Hz for the cw section and was just curious about an additional 250Hz Filter: I would never put it out again. My normal work is done in the 400 range, if I want more "atmosphere" I open up to 1K but when it comes to contest work the 250 is a cornerstone for solid work even in horrible situations.

regards, Juergen (dl4maq)

[WB8ENE]

How does the loss of the 250Hz compare to the 400HZ.  I would think that there would not be much difference since they only differ by 65Hz.  Would someone who has used both of these filters respond to this?  Thanks.

Art, WB8ENE

[Doug Turnbull]

What is the big deal with some loss in a narrow filter when the filter set up includes compensation for the loss.  I bet the other filters also have insertion loss but this loss is pretty uniform and already compensated for with adequate gain.   A bit of loss in the IF which is compensated for is surely nothing new or worrisome.

            73 Doug EI2CN  

On Wed, 17 Feb 2010 04:45:24 -0800 (PST), WB8ENE <[hidden email]> wrote:

>
> How does the loss of the 250Hz compare to the 400HZ.  I would think that
> there would not be much difference since they only differ by 65Hz.  Would
> someone who has used both of these filters respond to this?  Thanks.
>
> Art, WB8ENE
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[Bill W4ZV]

WB8ENE wrote

How does the loss of the 250Hz compare to the 400HZ.

http://www.inrad.net/product.php?productid=150&cat=140&page=1 (see plot)
http://www.inrad.net/product.php?productid=149&cat=140&page=1 (no plot)

"Typical Insertion Loss   250 Hz: < 9 dB; 500 Hz: < 7 dB"

Both appear to be ~9 dB.

73,  Bill