[RTTY] Re: Noise with MMTTY

[llindblom at juno.com]

I typed AFC in the fist sentence and it should of been AGC, me bad!

-- llindblom at juno.com wrote:

This is  very reason I alway turn off the AFC before diving into the crowded portions of any band on any mode.  AGC off can be harder on the ears at times but this prevents a strong nuisance signal from totally covering up the ESP signal you are trying to copy.

73 W0ETC

-- "Don Inbody" <ad0k at inbody.net> wrote:
-----------------------------SNIP------------------------------ 

My only problem is the tendency of my rig (TS-430) to clamp down the AGC
when a nearby loud signal comes on, thereby virtually eliminating the weaker
signal I may be copying.  In that circumstance, a tight filter (or moving
the IF shift) will help.

Don

Don Inbody/AD0K
QSL via LotW and eQSL
-----Original Message-----
From: rtty-bounces at contesting.com [mailto:rtty-bounces at contesting.com] On
Behalf Of llindblom at juno.com
Sent: Tuesday, March 23, 2004 13:07
To: wrt at dslextreme.com
Cc: RTTY at CONTESTING.COM
Subject: Re: [RTTY] Re: Noise with MMTTY


As some one who over the past 40+ years has done a lot of all nighters on 80
and 160 during SSB contests, I learned I could copy signals better with the
widest filters in the rig. Eventually I started doing that on CW and it
worked well.  

During BARTG I decide to try and take this one step further. For the weakest
of signals it seemed that going to the wide filters in my IC-775 did the
trick and let MMTTY decode cleaner.  Or, did the signal peak when I went
wide and dive when I went back to a narrower setting? 

73 W0ETC


-- Bill Turner <wrt at dslextreme.com> wrote:
On Tue, 23 Mar 2004 10:29:59 -0600, Charles Morrison wrote:

>I can't speak to this issue directly.  However, on the human factors side
>people doing signal detection research stumbled across something that is
>counter intuitive.  Is it easier to copy a weak CW signal on a quiet or
>noisy band?
>Many people will say it is easiest to copy CW on a quiet band.  However,
>under controlled testing people did a better job of copying a weak CW
signal
>in noise than when there was no noise.  A demonstration of this on NPR
>nearly blew me away.  The played 10 seconds of what to the human ear
sounded
>like silence but actually contained a very low level CW signal.  When noise
>was added in the CW signal was very obvious.  Of course too much noise mask
>the signal entirely.
>I doubt electronic circuits/software work the same as the human brain.
But,
>the next time you operate the original digital mode don't cuss any noise
for
>it might be help your brain detect a signal that it otherwise might not
>process.

_________________________________________________________

I've noticed a similar effect on CW myself.  Often I can copy CW better
with a wide filter instead of a narrow one, even though the apparent
noise is more.  Strange.

--
Bill, W6WRT
QSLs via LoTW

_______________________________________________
RTTY mailing list
RTTY at contesting.com
http://lists.contesting.com/mailman/listinfo/rtty

_______________________________________________
RTTY mailing list
RTTY at contesting.com
http://lists.contesting.com/mailman/listinfo/rtty

_______________________________________________
RTTY mailing list
RTTY at contesting.com
http://lists.contesting.com/mailman/listinfo/rtty

_______________________________________________
RTTY mailing list
RTTY at contesting.com
http://lists.contesting.com/mailman/listinfo/rtty