700 Hz roofing filters

[Ken Chandler]

I'm a 99% cw op, mine are 2.7 (soon 2.8) 2.1, 500, 400, 200. Sub is 2.7, 500.
The 400 I use always for contesting.

Doing CQ WW RTTY as a low power multi single, this weekend as first time ever on this mode have WinTest es mmtty es setup for AFSK A.

What is the preferred filter width min es max in these crowded bands.
Hopefully the P3 will give me an edge squeezing in somewhere.

Ken..G0ORH

CW4EVER

Sent from my iPhone

     


On 21 Sep 2010, at 23:07, Wayne Burdick <[hidden email]> wrote:

> 700 Hz is a useful CW/DATA filter bandwidth, certainly. I'm not  
> surprised that some K3 owners are interested in this.
>
> Personally, I prefer much narrow CW/DATA bandwidths, and I use all  
> modes. The lineup I use (and generally recommend) is:
>
> FL1   13 kHz (FM)
> FL2   6 kHz (AM/ESSB)
> FL3   2.7 or 2.8 kHz (SSB and casual CW/DATA tuning)
> FL4   400 or 500 Hz (normal CW/DATA)
> FL5   200 Hz (CW/DATA in heavy QRM)
>
> 73,
> Wayne
> N6KR
>
>
> ______________________________________________________________
> 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

______________________________________________________________
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

[Richard Ferch]

Ken,

You wmay get a number of different answers on this, but mine would be:
max filter width 500 Hz while tuning around, and minimum width 250 Hz. A
normal operating setting might be 350-400 Hz. I believe your 200 Hz
roofing filter will be too narrow to be useful for RTTY.

More importantly, I believe you should turn AFC off in MMTTY. MMTTY does
its own filtering, so if AFC is off, changing the filter width setting
may not make as much difference as you might have expected, but if AFC
is on, narrow filtering will be essential to try to stop the receive
decoder from being pulled away by nearby signals.

In AFSK, you can simply operate with AFC off and NET on all the time.
When you are CQing, you can use RIT to copy off-frequency callers and
embed a clear RIT command in your CQ message, the same as you would in CW.

Alternatively, when you are CQing you can turn AFC on and NET off and
have your CQ message invoke the HAM default (MMTTY's software equivalent
to clearing RIT); when you are S&Ping, you would turn AFC off and NET
on. I don't know about WinTest, but N1MM Logger has settings to automate
all of this.

73,
Rich VE3KI


G0ORH wrote:

> Doing CQ WW RTTY as a low power multi single, this weekend as first time ever on this \
> mode have WinTest es mmtty es setup for AFSK A.
>
> What is the preferred filter width min es max in these crowded bands.
> Hopefully the P3 will give me an edge squeezing in somewhere.
______________________________________________________________
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

[Tony Fegan VE3QF]

This is Tony's son Paul, sometime Monday night my father passed away in
his sleep. We used to joke about this being the best way to move on and
I'm glad that this was how he left this world. If anyone needs to
contact me for any reason I can be reached at [hidden email].

Paul.
______________________________________________________________
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