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Zero beat

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Ralph Parker

Zero beat

>Not really. Spots typically are to the nearest 100 Hz...

Really. Whatever frequency the spots report, EVERYBODY (well, almost) calls
on that freq., whether that is my exact frequency or not, making them
impossible (well, almost) to differentiate. THAT'S the problem.
I daresay most of us old-timers know that.

I would suggest that newcomers stick with one favourite pitch. Your ear
will soon get used to it, and tuning for 'zero beat' will become automatic.

Funny how 'zero beat' means something different today compared to years ago.

Respectfully submitted,
Ralph, VE7XF

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Dunc Carter - W5DC

Re: Zero beat

Current practice seems to be:
1. Click on the receive frequency of a spot.
2. Tune up at length on that frequency.
3. Warm up your fingers sending.
4. Then listen, maybe.

This practice really makes me appreciate the "low power, seldom tune"
features of my K3. I've actually had to tune the K3 on 80 yesterday
since my antenna insulators are coated with ice with an overnight low
temperature of minus 13 F.

Dunc, W5DC

On 2/1/2011 12:03 PM, Ralph Parker wrote:

>> Not really. Spots typically are to the nearest 100 Hz...
> Really. Whatever frequency the spots report, EVERYBODY (well, almost) calls
> on that freq., whether that is my exact frequency or not, making them
> impossible (well, almost) to differentiate. THAT'S the problem.
> I daresay most of us old-timers know that.
>
> I would suggest that newcomers stick with one favourite pitch. Your ear
> will soon get used to it, and tuning for 'zero beat' will become automatic.
>
> Funny how 'zero beat' means something different today compared to years ago.
>
> Respectfully submitted,
> Ralph, VE7XF
>
> ______________________________________________________________
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Scott Ellington

Re: Zero beat

In reply to this post by Ralph Parker

Not really, it's just the way we do it. Years ago, matching frequencies meant literally listening for the zero-frequency beat. It was always difficult, because the audio response of any receiver, as well as that of the human ear, drops off at low frequencies. Now you can achieve the same thing by matching the audio frequencies of the spot tone and the received signal, both of which are within the audio response range of both the receiver and our hearing. One can easily match frequencies within fraction of a Hz with this method. This only works, however, because receivers now have tracking sidetones, generated by exactly the same frequencies which produce the received signal beat note.

73,

Scott K9MA

On Feb 1, 2011, at 1:03 PM, Ralph Parker wrote:

> Funny how 'zero beat' means something different today compared to years ago.

Scott Ellington
Madison, Wisconsin
USA

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Pete Smith N4ZR

Re: Zero beat

In reply to this post by Ralph Parker

What I should have explained ... is that I find when I jump to a Skimmer
spot that it is rarely in genuine zero-beat, so I typically tune
manually before calling. In any case, I usually don't have much
competition (unlike traditional packet pileups because I get there early.

73, Pete N4ZR

The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000

On 2/1/2011 2:03 PM, Ralph Parker wrote:

Rex Lint

Re: Zero beat

In reply to this post by Scott Ellington

Well, it's not tuning to have the tone go to zero cycles, it's tuning to
have the BEAT between the two tones (from your vfo and his transmitter) go
to zero. Like tuning him in at a tome of 400 cycles, then adjusting your
VFO until it was 400 cycles, not 403 or 402, which makes a "wah-wah" sound
at 3 or 2 hz. Then you're "zero-beat."

My only qualification on this topic is that I was there when dirt was
invented.

-Rex-

K1HI - ex W1HWB, WA1YUK, W5PUG, K6RLX, KN6RLX
Rex Lint
Merrimack, NH
WWW.QRZ.COM/db/k1hi

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Scott Ellington
Sent: Tuesday, February 01, 2011 2:16 PM
To: Elecraft Reflector
Subject: Re: [Elecraft] Zero beat

Not really, it's just the way we do it. Years ago, matching frequencies
meant literally listening for the zero-frequency beat. It was always
difficult, because the audio response of any receiver, as well as that of
the human ear, drops off at low frequencies. Now you can achieve the same
thing by matching the audio frequencies of the spot tone and the received
signal, both of which are within the audio response range of both the
receiver and our hearing. One can easily match frequencies within fraction
of a Hz with this method. This only works, however, because receivers now
have tracking sidetones, generated by exactly the same frequencies which
produce the received signal beat note.

73,

Scott K9MA

On Feb 1, 2011, at 1:03 PM, Ralph Parker wrote:

> Funny how 'zero beat' means something different today compared to years
ago.

Scott Ellington
Madison, Wisconsin
USA

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Chester Alderman

Re: Zero beat

In reply to this post by Scott Ellington

Nooooooooooo! If you served on an aircraft carrier for three years, with
Navy jets literally landing on a 13-inch thick steel deck just seven feet
above your bed, there are a LOT of things you cannot hear anymore and
matching audio tones is one of them!!

There are exception to every "One can easily....."!

73,
Tom - W4BQF

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Scott Ellington
Sent: Tuesday, February 01, 2011 2:16 PM
To: Elecraft Reflector
Subject: Re: [Elecraft] Zero beat

Not really, it's just the way we do it. Years ago, matching frequencies
meant literally listening for the zero-frequency beat. It was always
difficult, because the audio response of any receiver, as well as that of
the human ear, drops off at low frequencies. Now you can achieve the same
thing by matching the audio frequencies of the spot tone and the received
signal, both of which are within the audio response range of both the
receiver and our hearing. One can easily match frequencies within fraction
of a Hz with this method. This only works, however, because receivers now
have tracking sidetones, generated by exactly the same frequencies which
produce the received signal beat note.

73,

Scott K9MA

On Feb 1, 2011, at 1:03 PM, Ralph Parker wrote:

> Funny how 'zero beat' means something different today compared to years
ago.

Scott Ellington
Madison, Wisconsin
USA

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AC7AC

Re: Zero beat

CONTENTS DELETED

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Don Wilhelm-4

Re: Zero beat

Ron,

You are quite correct, but it is not all hearing loss, it is a case of
tone perception, and some of us are "tone-deaf" even without hearing
loss. Many suffer from "tone-deaf" problems. I used to break guitar
strings because I could not determine if I should tune it higher or
lower - I finally bought a device that helped a lot with that problem -
it got close, but not exact - once the tones were close enough that I
could discern the beat note, there was no problem in getting the guitar
tuned properly.

Now for those of us with tone discernment problems like mine, when the
two tones are close, we can hear the low frequency "wow-wow" beat with
no problem - the real problem is getting the two tones close enough to
hear the "wow-wow". Fortunately, the K3 has the CWT indicator which is
a big help to me.

73,
Don W3FPR

On 2/1/2011 9:16 PM, Ron D'Eau Claire wrote:

> You may be quite right, Tom. Many of us have various levels of hearing loss.
>
> However, the "red flag" that causes people to say things like that is the
> use of the phrase "matching tones".
> There is *no* "matching tones" in the process of zero beating, which gives
> the impression the person is trying to do the wrong thing!
>
> We don't care what frequency the "tones" we're hearing are. We are listening
> for the third tone that disappears when "zero beat" is achieved. So it's
> only a matter of hearing whether a tone is there or not.
>
> It WAS easier in the "old days" because there was only one tone and we tuned
> until it disappeared completely. Nowadays we have three tones, only one of
> which disappears at 'zero beat'.
>
> Having the other two tones, whatever frequency they might be, at the *same*
> level makes the third tone as loud as possible so it's easier to hear when
> it disappears.
>
> Having followed this thread many times over the past decade, I'm becoming
> convinced that some people have a very hard time hearing more than one tone
> at a time. Even minor QRM on a CW signal stops them cold unless they can
> filter it out in the receiver. For such people hearing the third tone is
> probably very difficult or impossible.
>
> Many of us OTs have for years used very broad receivers on CW and learned
> long ago to listen to several signals at once, picking out the one we want
> to copy just as one picks out one conversation out of many in a crowded
> room. Perhaps what we're seeing today is a side effect of modern receivers
> where listening through real QRM is almost unknown.
>
> 73,
>
> Ron AC7AC
>

Scott Ellington

Re: Zero beat

In reply to this post by Ralph Parker

I must disagree with Ron about the "matching tones". When you "zero beat" the transceiver with a received signals using the sidetone or spot tone, matching the frequencies of those two audio tones is exactly what you are doing. With a tracking sidetone, as in most modern transceivers, those two frequencies are the same when the transmitter is on exactly the same frequency as the received signal. The PROCESS the operator uses to get those two frequencies to be the same can ultimately be to listen for the slow beat between them and to make the beat frequency got to nearly zero. That only works, however, after they are very close, and you have to somehow get them that close. You don't have to have perfect musical pitch to determine whether one is higher or lower in pitch than the other, and that's how most of us get close. Indeed, for even the most demanding CW operating, you don't have to be EXACTLY on the other station's frequency: within 10-20 Hz is just about always close enough. You often want to deliberately be offset slightly to avoid QRM, etc. I think the problem arises when operators are so unaware of the difference between the sidetone and the received signal pitches that they end up calling 400 Hz or more off, perhaps outside the passband of the other station, and/or on top of an adjacent station. Some, it seems, assume that if they can hear the other station at all, they must be on the same frequency. Even with a narrow CW filter, that could be 400 Hz off, and well outside the other station's passband..

I don't mean to disparage those with serious hearing losses, some of which I'm sure can make this tone matching difficult or impossible. (Most of us, after all, are of an age when hearing loss is common. Years of operating without AGC didn't help.) These folks obviously have to use other methods, such as Dual PB, CWT, APF, or just a narrower filter. I doubt, however, that all the operators who call me way, way off frequency have this problem.

I still think Wayne and Eric should come up with the "Reverse CWT", which would put the OTHER station's transmitter on frequency. (Tongue firmly in cheek!)

73,

Scott K9MA

*********

AC7AC wrote:

You may be quite right, Tom. Many of us have various levels of hearing loss.

However, the "red flag" that causes people to say things like that is the

use of the phrase "matching tones".

There is *no* "matching tones" in the process of zero beating, which gives

the impression the person is trying to do the wrong thing!

We don't care what frequency the "tones" we're hearing are. We are listening

for the third tone that disappears when "zero beat" is achieved. So it's

only a matter of hearing whether a tone is there or not.

It WAS easier in the "old days" because there was only one tone and we tuned

until it disappeared completely. Nowadays we have three tones, only one of

which disappears at 'zero beat'.

Having the other two tones, whatever frequency they might be, at the *same*

level makes the third tone as loud as possible so it's easier to hear when

it disappears.

Having followed this thread many times over the past decade, I'm becoming

convinced that some people have a very hard time hearing more than one tone

at a time. Even minor QRM on a CW signal stops them cold unless they can

filter it out in the receiver. For such people hearing the third tone is

probably very difficult or impossible.

Many of us OTs have for years used very broad receivers on CW and learned

long ago to listen to several signals at once, picking out the one we want

to copy just as one picks out one conversation out of many in a crowded

room. Perhaps what we're seeing today is a side effect of modern receivers

where listening through real QRM is almost unknown.

73,

Ron AC7AC
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AC7AC

Re: Zero beat

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Geoffrey Mackenzie-Kennedy

OT K3 Contesters Group (Yahoo)

In reply to this post by Scott Ellington

Sorry to take up some bandwidth, but I would appreciate some advice.

Yesterday I received an invitation by e-mail to join a "K3 Contesters Group"
(Yahoo), but so far I do not know whether or not this Group actually exists.
Could somebody please tell me if it does or does not exist.

Why I should receive this invitation is beyond me because I do not own a K3,
(yes yes I know that I should have a K3), but perhaps because I worked
VP8ORK via 15m ESP somebody assumed that I do have a K3.

73,

Geoff
GM4ESD

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M0XDF

Re: OT K3 Contesters Group (Yahoo)

Yes it exists, the invitation is legitimate.
I'm not the owner or moderator, so can't explain why you received the invite.
The Yahoo group is to specifically discuss the use of K3s in contesting.

On 3 Feb 2011, at 00:07, Geoffrey Mackenzie-Kennedy wrote:

> Sorry to take up some bandwidth, but I would appreciate some advice.
>
> Yesterday I received an invitation by e-mail to join a "K3 Contesters Group"
> (Yahoo), but so far I do not know whether or not this Group actually exists.
> Could somebody please tell me if it does or does not exist.
>
> Why I should receive this invitation is beyond me because I do not own a K3,
> (yes yes I know that I should have a K3), but perhaps because I worked
> VP8ORK via 15m ESP somebody assumed that I do have a K3.
>
> 73,
>
> Geoff
> GM4ESD