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What CW Filters do others have

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ac8jd

What CW Filters do others have

I am ready to pull the trigger on a CW filter for my K3. I am curious to hear opinions of others who have used the 8 pole 400hz filter and the 5 pole 500hz filter. I am not a contester by any means so this is for casual CW operating.

All thoughts and opinions are welcome!

Thanks!
AC8JD

Joe Subich, W4TV-4

Re: What CW Filters do others have

> I am curious to hear opinions of others who have used the 8 pole
> 400hz filter and the 5 pole 500hz filter.

Having used both, I can't tell much, if any, difference in normal
CW operation. There are perhaps three advantages to the 400 Hz
filter:

1) it is nominally zero offset - if you plan to get the KRX3
you will not need to be concerned about matching offsets
in the second filter at a later date.
2) The nominally tighter bandwidth and steeper skirts are very
handy RTTY and avoid the need to a tighter RTTY filter
3) The steeper skirts provide slightly more protection against
AGC pumping from the behemoth +/- 500 Hz away. This is
probably something one will not encounter outside a contest
and I've found more problems with "dirty signals" (clicks)
than with AGC plumping. The filter isn't going to resolve
clicks!

Both my K3/KRX3s now have a pair of the 400 Hz filters with a
single 200 Hz filter in the main Rx if I need anything tighter.

73,

... Joe, W4TV

On 1/5/2013 1:36 PM, ac8jd wrote:

> I am ready to pull the trigger on a CW filter for my K3. I am curious to
> hear opinions of others who have used the 8 pole 400hz filter and the 5 pole
> 500hz filter. I am not a contester by any means so this is for casual CW
> operating.
>
> All thoughts and opinions are welcome!
>
> Thanks!
> AC8JD
>
>
>
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/What-CW-Filters-do-others-have-tp7568250.html
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RobertG

Re: What CW Filters do others have

In reply to this post by ac8jd

I have the 2.9, 1.9, .500 and .200 KHz filters. All are 8-pole with the
exception of the 200cps filter from Elecraft which is 5-pole. I bought
the 500KHz 8-pole directly from Inrad since the 400cps filter seemed too
close to the .200KHz for my taste, and because there has been [in the
past] some chatter here on the reflector to the same effect. All filters
in the K3 provide adjacent channel protection, while the DSP filter(s)
provides the final selectivity. If you're not interested in contesting,
then the 8-pole narrow filters are probably not that important. My
general sense is that 8-pole filters, while overkill in many situations,
are not so much more expensive and give one state of the art filtering
that stands up over time. While I don't know for sure, I'm under the
impression that they are also easier to sell if one wants to go in
another direction. I'd probably go with the .400KHz 8-pole which no
doubt will serve you well in casual CW.

...robert

On 1/5/2013 18:36, ac8jd wrote:

--
Robert G Strickland, PhD ABPH - KE2WY
verizon.net.usa
Syracuse, New York, USA
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ac8jd

Re: What CW Filters do others have

Thanks all for the replies. I was leaning toward the 8 pole 400hz filter since it is described as having steeper skirts for cutting off adjacent interference. I am a person who runs the K3 on cw with the DSP at 400hz as it stands today with the dual PB option (narrow) on at all times. I find its a cleaner signal to listen to. You just have to be careful to tune around the bands slowly or you will miss signals. :)

So it seems most favor the 400hz filter for what I was understanding it to be so I guess my gut was right! I also ordered the internal antenna tuner. I just sold my Ameritron AL811 amplifier and have my Palstar AT2K tuner on the market as well. My plan is to run with the internal antenna tuner and 100w only until I can save enough pennies and get the KAT500 and KPA500 and have the entire elecraft line! Plus it will all conserve some space on my shack desk! :)

73!
AC8JD

ve3dvy

Re: What CW Filters do others have

just to add my two pennies, I am what I would call a casual CW
contester. I got the 250Hz 8 pole now I often think that was not the
best decidion and should have used the 400Hz filter in rare cases the
250hz pay off in tight situation. Most often the 400hz would have
probably done better as I don't see that many big signals here and the
chances that there is one withing 400HZ is not that often. when I am
wider than 250 I do find that there is sometimes a biggies too close for
the 1.8 filter and agc starts to get in the way. so the 400 would have
been best for me.

. On 1/5/2013 11:31 PM, ac8jd wrote:

> Thanks all for the replies. I was leaning toward the 8 pole 400hz filter
> since it is described as having steeper skirts for cutting off adjacent
> interference. I am a person who runs the K3 on cw with the DSP at 400hz as
> it stands today with the dual PB option (narrow) on at all times. I find
> its a cleaner signal to listen to. You just have to be careful to tune
> around the bands slowly or you will miss signals. :)
>
> So it seems most favor the 400hz filter for what I was understanding it to
> be so I guess my gut was right! I also ordered the internal antenna tuner.
> I just sold my Ameritron AL811 amplifier and have my Palstar AT2K tuner on
> the market as well. My plan is to run with the internal antenna tuner and
> 100w only until I can save enough pennies and get the KAT500 and KPA500 and
> have the entire elecraft line! Plus it will all conserve some space on my
> shack desk! :)
>
> 73!
> AC8JD
>
>
>
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/What-CW-Filters-do-others-have-tp7568250p7568292.html
> Sent from the Elecraft mailing list archive at Nabble.com.
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

ac8jd

Re: What CW Filters do others have

I am impressed with the turn around time at Elecraft! I ordered the parts on Saturday night and they were at my door step Tuesday when I got home from work.

I ordered the internal antenna tuner and the 400hz 8 pole cw filter. I was in and out of the K3 with the new parts in 30 minutes.

After some updates to the rig's software I was off and running. My impressions of the 400hz filter are high! it really "hugs" the signal and cuts out background band noise. Its amazing the stark difference when I open the width up from 400hz to 450hz. I am very glad I made the choice to get this filter!

73!
AC8JD