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Interesting QSO

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wayne burdick

Interesting QSO

Administrator

I just finished a QSO with a QRP station in Bend, Oregon on 40 m that was memorable for a couple of reasons: First, that we managed it all despite awful atmospheric noise and poor propagation, and second, that it highlighted many the K4's tools for digging out weak signals.

By the end of the QSO I was configured like this:

- diversity mode (wire antenna on main RX, vertical on sub)
- 100 Hz primary RX filter bandwidth
- 50 Hz APF (audio peaking filter)
- NB & NR on
- CW center pitch dialed down to 400 Hz

That final setting may have been optimum for my hearing range (we all lose higher-pitched response as we get older), but it also seemed to keep the week signal highlighted during static crashes. I'll be experimenting with this on DX signals.

73,
Wayne
N6KR

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Sverre Holm (LA3ZA)

Re: Interesting QSO

Wayne.

A CW sidetone pitch of 400 Hz is consistent with what little research there
is on this. A paper from 1992 says that "/All subjects improved their
recognition as the frequency was lowered to 500 Hz, some even at 250 Hz./"

See
https://la3za.blogspot.com/2013/10/studies-on-morse-code-recognition.html

-----
Sverre, LA3ZA

K2 #2198, K3 #3391,
LA3ZA Blog: http://la3za.blogspot.com,
LA3ZA Unofficial Guide to K2 modifications: http://la3za.blogspot.com/p/la3za-unofficial-guide-to-elecraft-k2.html
--
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Sverre, LA3ZA

K2 #2198, K3 #3391,
LA3ZA Blog: http://la3za.blogspot.com,
LA3ZA Unofficial Guide to K2 modifications: http://la3za.blogspot.com/p/la3za-unofficial-guide-to-elecraft-k2.html

Wes Stewart-2

Re: Interesting QSO

In reply to this post by wayne burdick

I use 420 Hz +/- these days when DXing. With 40 year younger ears I used to use
500-600 Hz on MS and EME.

On 3/13/2021 11:50 AM, Sverre Holm (LA3ZA) wrote:

> Wayne.
>
> A CW sidetone pitch of 400 Hz is consistent with what little research there
> is on this. A paper from 1992 stated that "All subjects improved their
> recognition as the frequency was lowered to 500 Hz, some even at 250 Hz."
>
> See
> https://la3za.blogspot.com/2013/10/studies-on-morse-code-recognition.html
>
>
>
> -----
> Sverre, LA3ZA

Jim Brown-10

Copying CW and Pitch

In reply to this post by Sverre Holm (LA3ZA)

On 3/13/2021 10:48 AM, Sverre Holm (LA3ZA) wrote:
> A CW sidetone pitch of 400 Hz is consistent with what little research there
> is on this. A paper from 1992 says that "/All subjects improved their
> recognition as the frequency was lowered to 500 Hz, some even at 250 Hz.

As a retired designer of large sound systems, I had to learn a lot about
acoustics and psychoacoustics (the science of how humans' ear/brain
interprets what we hear). That science tells us that, like most of our
senses, hearing is logarithmic both with respect to frequency and
loudness. This means that our discrimination of one frequency as
compared to another increases with decreasing frequency. That is, we are
better able to separate signals from each other with RX pitch set to
lower frequencies.

73, Jim K9YC
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Dave Fugleberg

Re: Copying CW and Pitch

Jim, that’s an interesting bit of information. Is that the case even for
people who have excellent hearing at higher frequencies? In other words,
would people with excellent hearing at higher frequencies also benefit from
using a lower frequency side tone?

On Sat, Mar 13, 2021 at 5:45 PM Jim Brown <[hidden email]> wrote:

> On 3/13/2021 10:48 AM, Sverre Holm (LA3ZA) wrote:
> > A CW sidetone pitch of 400 Hz is consistent with what little research
> there
> > is on this. A paper from 1992 says that "/All subjects improved their
> > recognition as the frequency was lowered to 500 Hz, some even at 250 Hz.
>
> As a retired designer of large sound systems, I had to learn a lot about
> acoustics and psychoacoustics (the science of how humans' ear/brain
> interprets what we hear). That science tells us that, like most of our
> senses, hearing is logarithmic both with respect to frequency and
> loudness. This means that our discrimination of one frequency as
> compared to another increases with decreasing frequency. That is, we are
> better able to separate signals from each other with RX pitch set to
> lower frequencies.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
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>

Mike Cizek W0VTT

Re: Copying CW and Pitch

As a bass clef guy my entire life, I have my sidetone set at 300 Hz. Sometimes wish it would go lower.

----
73,
Mike Cizek W0VTT
Retired Bass Trombonist

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Dave Fugleberg
Sent: Saturday, 13 March, 2021 18:07
To: Elecraft List <[hidden email]>
Subject: Re: [Elecraft] Copying CW and Pitch

Jim, that’s an interesting bit of information. Is that the case even for people who have excellent hearing at higher frequencies? In other words, would people with excellent hearing at higher frequencies also benefit from using a lower frequency side tone?

On Sat, Mar 13, 2021 at 5:45 PM Jim Brown <[hidden email]> wrote:

> On 3/13/2021 10:48 AM, Sverre Holm (LA3ZA) wrote:
> > A CW sidetone pitch of 400 Hz is consistent with what little
> > research
> there
> > is on this. A paper from 1992 says that "/All subjects improved
> > their recognition as the frequency was lowered to 500 Hz, some even at 250 Hz.
>
> As a retired designer of large sound systems, I had to learn a lot
> about acoustics and psychoacoustics (the science of how humans'
> ear/brain interprets what we hear). That science tells us that, like
> most of our senses, hearing is logarithmic both with respect to
> frequency and loudness. This means that our discrimination of one
> frequency as compared to another increases with decreasing frequency.
> That is, we are better able to separate signals from each other with
> RX pitch set to lower frequencies.
>
> 73, Jim K9YC
> ______________________________________________________________
> 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 Message delivered to
> [hidden email]
>

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Drew AF2Z

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

My default sidetone pitch is 440 Hz, which is plenty sufficient (for me)
to discriminate between two very close signals signals, if they are not
too unequal in strength.

I am more interested in choosing the optimum pitch for particular filter
bandwidths and QRN conditions rather than for discriminating between
multiple stations. I suppose the wpm speed of the CW signal might also
come into play in optimum pitch selection. This is probably more
complicated than just "lower is better".

I'm looking forward to "live" adjustment of signal pitch on the K4.
Seems to me that adjusting the pitch of the signal would be the natural
final tweak needed to enhance it.

73,
Drew
AF2Z

On 03/13/21 18:44, Jim Brown wrote:

> On 3/13/2021 10:48 AM, Sverre Holm (LA3ZA) wrote:
>> A CW sidetone pitch of 400 Hz is consistent with what little research
>> there
>> is on this. A paper from 1992 says that "/All subjects improved their
>> recognition as the frequency was lowered to 500 Hz, some even at 250 Hz.
>
> As a retired designer of large sound systems, I had to learn a lot about
> acoustics and psychoacoustics (the science of how humans' ear/brain
> interprets what we hear). That science tells us that, like most of our
> senses, hearing is logarithmic both with respect to frequency and
> loudness. This means that our discrimination of one frequency as
> compared to another increases with decreasing frequency. That is, we are
> better able to separate signals from each other with RX pitch set to
> lower frequencies.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
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Jim Brown-10

Re: Copying CW and Pitch

In reply to this post by Dave Fugleberg

On 3/13/2021 4:06 PM, Dave Fugleberg wrote:
> Jim, that’s an interesting bit of information. Is that the case even for
> people who have excellent hearing at higher frequencies? In other words,
> would people with excellent hearing at higher frequencies also benefit from
> using a lower frequency side tone?

Yes.

73, Jim
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NK7Z

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

Jim,
Here is an interesting story:

I had a hearing test many years ago, and asked to see the results.
Turns out I had a null at some frequency I don't remember right now, but
it was exactly where I had selected my sidetone to be... My guess is
because I heard less noise there... Anyway--

I re-selected a new sidetone, lower in frequency, and on a small peak...
My CW speed for copy increased probably 10-15%.

Now whenever I get a hearing test, I ask for a copy, and put the
sidetone where my highest peak is, within the range Elecraft allows for
sidetone.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 3/13/21 3:44 PM, Jim Brown wrote:

Jim Brown-10

Re: Copying CW and Pitch

On 3/13/2021 9:37 PM, Dave Cole wrote:
> I had a hearing test many years ago, and asked to see the results. Turns
> out I had a null at some frequency I don't remember right now, but it
> was exactly where I had selected my sidetone to be... My guess is
> because I heard less noise there... Anyway--
>
> I re-selected a new sidetone, lower in frequency, and on a small peak...
> My CW speed for copy increased probably 10-15%.

One of the most common forms of hearing loss starts at the high
frequencies and works its way down with age, but that's far from
universal. When one or more notches develop at certain frequencies, it's
often the result of noise exposure at work.

73, Jim K9YC
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Edward H Russell

Re: Copying CW and Pitch

FWIW At my age hearing of both ears starts to roll off in the 4khz range. I can remember when the upper limit was 20+khz. I'm a bass player so my hearing is quite acute at low frequencies. However for CW I prefer to copy at about 625hz. This is with filters set in the 50-500hz range. If I try to copy at a lower frequency the signal tends to get shrouded by noise. I have not specifically tested the ability to discriminate close signals though.

ED / W2RF

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Jim Brown
Sent: Sunday, March 14, 2021 3:16 AM
To: [hidden email]
Subject: Re: [Elecraft] Copying CW and Pitch

On 3/13/2021 9:37 PM, Dave Cole wrote:
> I had a hearing test many years ago, and asked to see the results.
> Turns out I had a null at some frequency I don't remember right now,
> but it was exactly where I had selected my sidetone to be... My guess
> is because I heard less noise there... Anyway--
>
> I re-selected a new sidetone, lower in frequency, and on a small peak...
> My CW speed for copy increased probably 10-15%.

One of the most common forms of hearing loss starts at the high frequencies and works its way down with age, but that's far from universal. When one or more notches develop at certain frequencies, it's often the result of noise exposure at work.

73, Jim K9YC
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Jim Rhodes-2

Re: Copying CW and Pitch

Anymore I find that my hearing (except for that pesky tinnitus) rolls off
around 1800 hz. I can't hear my auduo in the monitor if I use a tone that
high anyway.

On Sun, Mar 14, 2021, 04:39 E.H. Russell <[hidden email]> wrote:

> FWIW At my age hearing of both ears starts to roll off in the 4khz range.
> I can remember when the upper limit was 20+khz. I'm a bass player so my
> hearing is quite acute at low frequencies. However for CW I prefer to copy
> at about 625hz. This is with filters set in the 50-500hz range. If I try to
> copy at a lower frequency the signal tends to get shrouded by noise. I have
> not specifically tested the ability to discriminate close signals though.
>
> ED / W2RF
>
>
>
>
> -----Original Message-----
> From: [hidden email] <[hidden email]>
> On Behalf Of Jim Brown
> Sent: Sunday, March 14, 2021 3:16 AM
> To: [hidden email]
> Subject: Re: [Elecraft] Copying CW and Pitch
>
> On 3/13/2021 9:37 PM, Dave Cole wrote:
> > I had a hearing test many years ago, and asked to see the results.
> > Turns out I had a null at some frequency I don't remember right now,
> > but it was exactly where I had selected my sidetone to be... My guess
> > is because I heard less noise there... Anyway--
> >
> > I re-selected a new sidetone, lower in frequency, and on a small peak...
> > My CW speed for copy increased probably 10-15%.
>
> One of the most common forms of hearing loss starts at the high
> frequencies and works its way down with age, but that's far from universal.
> When one or more notches develop at certain frequencies, it's often the
> result of noise exposure at work.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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k6dgw

Re: Copying CW and Pitch

In reply to this post by Mike Cizek W0VTT

So, you can hear the CTCSS tones? 😁

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 3/13/2021 4:47 PM, Mike Cizek W0VTT wrote:
> As a bass clef guy my entire life, I have my sidetone set at 300 Hz. Sometimes wish it would go lower.
>
> ----
> 73,
> Mike Cizek W0VTT
> Retired Bass Trombonist
>
>

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k6dgw

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

As a result of "adventures" in my 20's, the entire audio spectrum is a
"notch" with a peak around 590-600 Hz [see K9YC's last sentence].
That's where I put my sidetone/pitch. Around 1990 or so, I built a
little plywood cube with a Mother Bell insert from a standard black
telephone in it. I filled the box with cotton balls and put it on the
side of the rig, pointing up. Over-the-ear headphones had become
ubiquitous and the old "cans" were no longer available so the
"headphones on the desk" trick didn't work well. It was surprising what
I could copy with the little speaker that was mush with the phones on.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 3/13/2021 11:15 PM, Jim Brown wrote:

> On 3/13/2021 9:37 PM, Dave Cole wrote:
>> I had a hearing test many years ago, and asked to see the results.
>> Turns out I had a null at some frequency I don't remember right now,
>> but it was exactly where I had selected my sidetone to be... My
>> guess is because I heard less noise there... Anyway--
>>
>> I re-selected a new sidetone, lower in frequency, and on a small
>> peak... My CW speed for copy increased probably 10-15%.
>
> One of the most common forms of hearing loss starts at the high
> frequencies and works its way down with age, but that's far from
> universal. When one or more notches develop at certain frequencies,
> it's often the result of noise exposure at work.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> This list hosted by: http://www.qsl.net
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NK7Z

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

Yup, I sat close to a Linkurt Microwave transmitter for about 15 years,
(the power supply was an early switcher, and hence very loud), then next
to three Ampex VR1200's VTRs... All are horrific noisemakers.

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 3/13/21 11:15 PM, Jim Brown wrote:

> On 3/13/2021 9:37 PM, Dave Cole wrote:
>> I had a hearing test many years ago, and asked to see the results.
>> Turns out I had a null at some frequency I don't remember right now,
>> but it was exactly where I had selected my sidetone to be... My guess
>> is because I heard less noise there... Anyway--
>>
>> I re-selected a new sidetone, lower in frequency, and on a small
>> peak... My CW speed for copy increased probably 10-15%.
>
> One of the most common forms of hearing loss starts at the high
> frequencies and works its way down with age, but that's far from
> universal. When one or more notches develop at certain frequencies, it's
> often the result of noise exposure at work.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

chrisrut

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

On Sat, Mar 13, 2021 at 5:45 PM Jim Brown <[hidden email]> wrote:

Exactly right.

I have screaming-loud tinnitus at 1700hz - which is louder than
conversation, and rises and falls in pitch and volume with every
heartbeat... Fun, fun.

Changing sidetone from 800 to 400 made a HUGE difference in my ability to
copy through the chaos. I did so after reading an article 2 or 3 years ago
- perhaps those referenced, but I thought it was done by the USAF for
intercept operators in the late 60's - I may be mistaken.

ut for those who might not get the implications of what Jim said: our
perceptions depend less on absolute values than on the difference between
two values. That's why when you get "hot" with a fever, you "feel cold"
(and want heat, blankets, etc.): the outside air is now "colder" with
respect to your skin temp.

In terms of Morse, if the signal you're listening to is at 800 Hz, and the
interfering signal (or even the tone of the white noise) is at 700 Hz, the
100hz difference amounts to just 12%. However, if the desired signal is at
400 Hz, and the interfering signal at 300, that 100hz difference is now
25%. At 300/200, it's 50%. Bigger differences are easier to copy.

I did have to reprogram myself to listen at the lower frequency -
familiarity had bred contentment.

73 Chris NW6V
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Brian D

Re: Copying CW and Pitch

In reply to this post by NK7Z

Iworked for years on 405 line TV transmitters. I had a notch of at least
40dB at 10.125khz. I was surprised how quickly it disappeared when 405 line
TV closed down, to be replaced by a rolloff at 16kHz.

I now roll off much lower, and keep moving my default cw sidetone as it
seems to produce a notch after a few contests, I'm currently at 650Hz but
will try 700 again soon.

Dave Cole <[hidden email]> wrote:

> > One of the most common forms of hearing loss starts at the high
> > frequencies and works its way down with age, but that's far from
> > universal. When one or more notches develop at certain frequencies, it's
> > often the result of noise exposure at work.
> >

--
Brian D
G3VGZ Yarm England
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NK7Z

Re: Copying CW and Pitch

Yup, I have a notch at the old sweep frequency as well... :)

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 3/14/21 4:13 PM, Brian D wrote:

> Iworked for years on 405 line TV transmitters. I had a notch of at least
> 40dB at 10.125khz. I was surprised how quickly it disappeared when 405 line
> TV closed down, to be replaced by a rolloff at 16kHz.
>
> I now roll off much lower, and keep moving my default cw sidetone as it
> seems to produce a notch after a few contests, I'm currently at 650Hz but
> will try 700 again soon.
>
>
>
> Dave Cole <[hidden email]> wrote:
>
>>> One of the most common forms of hearing loss starts at the high
>>> frequencies and works its way down with age, but that's far from
>>> universal. When one or more notches develop at certain frequencies, it's
>>> often the result of noise exposure at work.
>>>
>
>

Tony Estep

Re: Copying CW and Pitch

In reply to this post by Jim Brown-10

On Sat, Mar 13, 2021 at 5:45 PM Jim Brown <[hidden email]> wrote:

> ....like most of our
> senses, hearing is logarithmic both with respect to frequency and
> loudness. This means that our discrimination of one frequency as
> compared to another increases with decreasing frequency....

this is the Weber-Fechner law. It is claimed to hold true for physical
perceptions, e.g a blindfolded person’s perception of an increase in a
weight he is holding is proportional to the percentage increases, not to
the absolute amount of weight added.

https://en.m.wikipedia.org/wiki/Weber%E2%80%93Fechner_law

73,
Tony KT0NY
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KE8G-2

Re: Copying CW and Pitch

In reply to this post by chrisrut

Yes, I agree!

I had brought up the same subject in the CWops Group a while back and found
the same thing. When I started out in ham radio 40+ years ago, my CW
sidetone was around 700-750 Hz, a very nice sweet spot. As I grew older,
the sidetone frequency has been decreasing. Now at 70 years old, I am at
420 Hz and that's the new sweet spot.

I did an unscientific study by operating the Wednesday CWTs at different
sidetone frequencies, just to see if there was a difference. Believe me,
there was! As I increased the frequency, my effectiveness of hearing the
CW signals and separating them decreased. I finally stopped at 700 Hz, as
I was convinced that my hearing had changed and the lower frequency was
definitely better for my ears.

73 de Jim - KE8G

On Sun, Mar 14, 2021 at 7:13 PM Chris R. NW6V <[hidden email]> wrote:

> On Sat, Mar 13, 2021 at 5:45 PM Jim Brown <[hidden email]>
> wrote:
>
> > On 3/13/2021 10:48 AM, Sverre Holm (LA3ZA) wrote:
> > > A CW sidetone pitch of 400 Hz is consistent with what little research
> > there
> > > is on this. A paper from 1992 says that "/All subjects improved their
> > > recognition as the frequency was lowered to 500 Hz, some even at 250
> Hz.
> >
> > As a retired designer of large sound systems, I had to learn a lot about
> > acoustics and psychoacoustics (the science of how humans' ear/brain
> > interprets what we hear). That science tells us that, like most of our
> > senses, hearing is logarithmic both with respect to frequency and
> > loudness. This means that our discrimination of one frequency as
> > compared to another increases with decreasing frequency. That is, we are
> > better able to separate signals from each other with RX pitch set to
> > lower frequencies.
> >
> > 73, Jim K9YC
>
> Exactly right.
>
> I have screaming-loud tinnitus at 1700hz - which is louder than
> conversation, and rises and falls in pitch and volume with every
> heartbeat... Fun, fun.
>
> Changing sidetone from 800 to 400 made a HUGE difference in my ability to
> copy through the chaos. I did so after reading an article 2 or 3 years ago
> - perhaps those referenced, but I thought it was done by the USAF for
> intercept operators in the late 60's - I may be mistaken.
>
> ut for those who might not get the implications of what Jim said: our
> perceptions depend less on absolute values than on the difference between
> two values. That's why when you get "hot" with a fever, you "feel cold"
> (and want heat, blankets, etc.): the outside air is now "colder" with
> respect to your skin temp.
>
> In terms of Morse, if the signal you're listening to is at 800 Hz, and the
> interfering signal (or even the tone of the white noise) is at 700 Hz, the
> 100hz difference amounts to just 12%. However, if the desired signal is at
> 400 Hz, and the interfering signal at 300, that 100hz difference is now
> 25%. At 300/200, it's 50%. Bigger differences are easier to copy.
>
> I did have to reprogram myself to listen at the lower frequency -
> familiarity had bred contentment.
>
> 73 Chris NW6V
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