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K3 Audio routing question

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g0afh

K3 Audio routing question

Hi

Is there a way to get the audio from the sub receiver into both ears
without external switching?

Here is why I want to do it.

K3 in diversity mode so that frequency and filtering is locked together.
Main RX on an antenna pointing in one direction.
Sub RX on an antenna pointing in different direction.

If I am called by a weak station on the Sub RX and I have QRM on the
main RX I'd like to switch both ears across to the Sub RX to concentrate
on the weak station.. As far as I can tell I can't do this in the K3.

73
Ian
G0AFH

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KK7P

Re: K3 Audio routing question

> Is there a way to get the audio from the sub receiver into both ears
> without external switching?

Yes. See the firmware release notes and CONFIG:L-MIX-R

73,

Lyle KK7P
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The Smiths

Re: K3 Audio routing question

In reply to this post by g0afh

I've asked for this feature to be implemented as well. The feature is already available in the Config menu now, but it only works with Sub receiver ON. It does not however work when Diversity mode is on.. seems a little odd, as that's the most important time to have the sub in your both ears... It's on the list I'm sure. We should see that soon hopefully.

> Date: Mon, 5 Jul 2010 21:08:31 +0100
> From: [hidden email]
> To: [hidden email]
> Subject: [Elecraft] K3 Audio routing question
>
> Hi
>
> Is there a way to get the audio from the sub receiver into both ears
> without external switching?
>
> Here is why I want to do it.
>
> K3 in diversity mode so that frequency and filtering is locked together.
> Main RX on an antenna pointing in one direction.
> Sub RX on an antenna pointing in different direction.
>
> If I am called by a weak station on the Sub RX and I have QRM on the
> main RX I'd like to switch both ears across to the Sub RX to concentrate
> on the weak station.. As far as I can tell I can't do this in the K3.
>
> 73
> Ian
> G0AFH
>
>
>
> ______________________________________________________________
> 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

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The Smiths

Re: K3 Audio routing question

In reply to this post by KK7P

Lyle,

As you know, this is NOT working in the Diversity mode as this person wants to use it. It is ONLY available with SUB mode at the time. Perhaps you can Stress to Wayne that he should finally make it available for use when in Diversity...

> Date: Mon, 5 Jul 2010 13:15:53 -0700
> From: [hidden email]
> To: [hidden email]
> CC: [hidden email]
> Subject: Re: [Elecraft] K3 Audio routing question
>
>
> > Is there a way to get the audio from the sub receiver into both ears
> > without external switching?
>
> Yes. See the firmware release notes and CONFIG:L-MIX-R
>
> 73,
>
> Lyle KK7P
> ______________________________________________________________
> Elecraft mailing list
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> Please help support this email list: http://www.qsl.net/donate.html

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Joe Subich, W4TV-4

Re: K3 Audio routing question

> As you know, this is NOT working in the Diversity mode as this person
> wants to use it. It is ONLY available with SUB mode at the time.
> Perhaps you can Stress to Wayne that he should finally make it
> available for use when in Diversity...

Making L-Mix-R function in diversity mode defeats the purpose of
diversity mode. Placing EITHER receiver in both ears during diversity
essentially disables diversity.

I hate to be the one to say "don't waste the programming time" but
this is another of those "enhancements" that is a complete waste of
programmer time and does not make *ANY* practical sense.

73,

... Joe, W4TV

On 7/5/2010 4:41 PM, The Smiths wrote:

>
> Lyle,
>
> As you know, this is NOT working in the Diversity mode as this person
> wants to use it. It is ONLY available with SUB mode at the time.
> Perhaps you can Stress to Wayne that he should finally make it
> available for use when in Diversity...
>
>> Date: Mon, 5 Jul 2010 13:15:53 -0700 From: [hidden email] To:
>> [hidden email] CC: [hidden email] Subject: Re:
>> [Elecraft] K3 Audio routing question
>>
>>
>>> Is there a way to get the audio from the sub receiver into both
>>> ears without external switching?
>>
>> Yes. See the firmware release notes and CONFIG:L-MIX-R
>>
>> 73,
>>
>> Lyle KK7P

W8JI

Re: K3 Audio routing question

In reply to this post by The Smiths

I'll echo W4TV's comments. The last thing anyone should do in diversity mode
is mix one channel into two ears!!!

The sole exception would be with perfectly phase stable relationship between
channels, such as would be obtained with **one set** of master oscillators
running into both receivers, where a control is available to shift phase
relationships of the two channels. In this case the two channels could be
mixed, and the result would be a peak or null as phase is rotated. I use a
system like this for direction finding on HF signals but it requires common
oscillator signals driving both receivers, so the Elecraft will not do this.

http://www.w8ji.com/polarization_and_diversity.htm

73 Tom

> I've asked for this feature to be implemented as well. The feature is
> already available in the Config menu now, but it only works with Sub
> receiver ON. It does not however work when Diversity mode is on.. seems a
> little odd, as that's the most important time to have the sub in your both
> ears... It's on the list I'm sure. We should see that soon hopefully.

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Don Wilhelm-4

Re: K3 Audio routing question

In reply to this post by The Smiths

Diversity reception requires hearing both the main and the subRX, each
with their own antenna.
I do not understand why one would want to listen to only the subRX when
doing diversity receive - it nullifies any benefit of diversity.
Can you explain further, maybe there is something I am missing.

73,
Don W3FPR

The Smiths wrote:
> Lyle,
>
> As you know, this is NOT working in the Diversity mode as this person wants to use it. It is ONLY available with SUB mode at the time. Perhaps you can Stress to Wayne that he should finally make it available for use when in Diversity...
>
>
>
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KK7P

Re: K3 Audio routing question

In reply to this post by W8JI

Perhaps the person who wishes to hear both receivers in diversity mode
is partially or fully deaf in one ear, so he or she needs the ability to
listen to both receivers in the same audio transducer.

My general inclination is to avoid "silicon cops" wherever possible as
long as the result of doing so does not cause harm.

Until this feature is available in the UI, you can use K3 Utility (or
perhaps program a logging macro, or ? but not a K3 button macro) to send
the string:

!BEFF;

to the K3 *after* you enter DIVRSTY mode.

This will route all audio to both ears until you exit DVRSTY, at which
time the A-MIX-B settings will take over.

I don't know if there will be side effects you'd rather not hear when
you do this, nor how often you'll have to send this string if you remain
in DIVRSTY mode.

But you can play with it and perhaps learn :-)

Enjoy!

73,

Lyle KK7P
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Jim Brown-10

Re: K3 Audio routing question

On Mon, 05 Jul 2010 15:53:39 -0700, Lyle Johnson wrote:

>Perhaps the person who wishes to hear both receivers in diversity mode
>is partially or fully deaf in one ear, so he or she needs the ability to
>listen to both receivers in the same audio transducer.

SNIP

>I don't know if there will be side effects you'd rather not hear when
>you do this, nor how often you'll have to send this string if you remain
>in DIVRSTY mode.

The problem is that there ARE SERIOUS DESTRUCTIVE SIDE EFFECTS from
mixing the audio from the two receivers in diversity mode because the two
receivers are not in phase with each other! That is, they are listening
to antennas that are PHYSICALLY SEPARATED, and thus are receiving the
signal at different times. AND they may also be hearing a direct and
reflected signal.

BTW -- an important definition. Inverting the signal by reversing wires
changes the POLARITY, not the phase. Phase is a continuously valued
function that can have any value between -infinity degrees and +infinity
degrees. The phase difference between two signals that differ in TIME is
proportional to their time offset.

When signals are precisely in phase AND in polarity with each other, they
can be summed together in the same channel and they will add. When
signals are precisely in phase and OUT of polarity, they will cancel. And
when signals are out of phase and IN polarity with each other, they can
add or cancel each other to varying degrees depending on the phase
relationship AT EACH FREQUENCY! The result of such a summation produces
a frequency response that looks like the teeth of a comb -- that is,
peaks and dips of addition and cancellation. In the pro audio world, it
is called comb filtering, or phasing, or flanging, depending on how the
delays are generated and used.

Bottom line -- it is a REALLY BAD IDEA to sum the output of both
receivers into the same channel! It is a REALLY GOOD IDEA to put one RX
in one ear and the other RX in the other, allowing the brain to combine
them.

73, Jim Brown K9YC

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The Smiths

Re: K3 Audio routing question

In reply to this post by Joe Subich, W4TV-4

I'm sorry but I completely disagree with you. Apparently you have not used diversity mode, or you haven't enjoyed it with an AB - BA (or AB- B) Mix mode on.
The point behind diversity is NOT to have one antenna in one ear and another in the other.. The purpose of Diversity is to enable the user to hear a signal from TWO different sources (Main and Sub Receiver with Horz/Vertical antennas) at the same time.

If you've ever used Diversity on a weak signal, or on a station that is phasing from Horz. to vertical polarization (as they do coming over the ocean all the time), then you would know that the signal "SWIMS" from your left ear to your right ear. This effect is NOT desirable when the frequency of the swimming becomes constant. The effect in fact can cause one to feel like they are on a rocking boat.
For this reason alone it is nice to be able to "add" the Sub (or Vertical phase) to the Main (Horz. phase) thereby canceling out the swimming effect on the listener. This allows for easy reception and a single signal that "fills" the ears with a constant audio even as the phase shifts from one polarity to the other.
In the AB - B mix mode the user can still ascertain which antenna the signal is coming from because even though the both phases are filling both ears, there is a slight "leaning" effect to the signal in the right ear when phasing to the Sub receiver.

Diversity mode has NOTHING to do with being forced to listen to 2 signals in one ear or the other. In any case, if this is the effect you want, feel free to keep the mixer off. For others, like myself who may have a beverage antenna and a vertical set up, we would like not to have to feel like we're sitting on the high seas while listening to a signal.
I completely understand why this other user in the group would request this feature. I was simply correcting Lyle that it was not available in the diversity mode as he suggested that it was. (or so it read)

Again, this Mix mode option IS available for Sub mode only, but it has not been implemented in the Diversity mode yet. I'm only asking that the switch gets flipped to allow it to be turned on while in Diversity mode.

> Date: Mon, 5 Jul 2010 17:43:29 -0400
> From: [hidden email]
> To: [hidden email]
> Subject: Re: [Elecraft] K3 Audio routing question
>
>
> > As you know, this is NOT working in the Diversity mode as this person
> > wants to use it. It is ONLY available with SUB mode at the time.
> > Perhaps you can Stress to Wayne that he should finally make it
> > available for use when in Diversity...
>
> Making L-Mix-R function in diversity mode defeats the purpose of
> diversity mode. Placing EITHER receiver in both ears during diversity
> essentially disables diversity.
>
> I hate to be the one to say "don't waste the programming time" but
> this is another of those "enhancements" that is a complete waste of
> programmer time and does not make *ANY* practical sense.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 7/5/2010 4:41 PM, The Smiths wrote:
> >
> > Lyle,
> >
> > As you know, this is NOT working in the Diversity mode as this person
> > wants to use it. It is ONLY available with SUB mode at the time.
> > Perhaps you can Stress to Wayne that he should finally make it
> > available for use when in Diversity...
> >
> >> Date: Mon, 5 Jul 2010 13:15:53 -0700 From: [hidden email] To:
> >> [hidden email] CC: [hidden email] Subject: Re:
> >> [Elecraft] K3 Audio routing question
> >>
> >>
> >>> Is there a way to get the audio from the sub receiver into both
> >>> ears without external switching?
> >>
> >> Yes. See the firmware release notes and CONFIG:L-MIX-R
> >>
> >> 73,
> >>
> >> Lyle KK7P
>
> ______________________________________________________________
> 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

Joe Subich, W4TV-4

Re: K3 Audio routing question

> I'm sorry but I completely disagree with you. Apparently you have
> not used diversity mode, or you haven't enjoyed it with an AB - BA
> (or AB- B) Mix mode on.

I'm sorry, you're wrong. If you MIX the two audio sources instead
of hearing them "swim" from ear to ear, you will hear them FADE
out completely as the phase differences cause them to cancel. "Swim"
is the mind's interpretation of the difference in phase and amplitude
between the PATH taken by the two signals.

What you accomplish by mixing is to undo all the benefits of diversity.
You have simply moved the point of phase cancellation from the single
antenna to the single headphone. You have gone to the great expense of
building/buying/installing a second antenna and buying/installing a
second, identical receiver so you can simply combine two non-coherent
audio sources instead of two non-coherent RF sources.

The only way one can "mix" the feeds from a diversity receive system
is to provide a voting/switching system that evaluates the signal to
noise ratio (in FM it's called "quieting") and selects the "better"
signal - not mixes the two.

> Again, this Mix mode option IS available for Sub mode only, but it
> has not been implemented in the Diversity mode yet. I'm only asking
> that the switch gets flipped to allow it to be turned on while in
> Diversity mode.

Mixing is appropriate when one has two completely different signals.
It is NOT appropriate when one has the same signal with a randomly
varying phase and amplitude difference. With two independent signals
there is no cancellation.

Again, enabling L - MIX - R in diversity is to waste programming
resources on something that is not only useless but will actually
result in decreased performance.

73,

... Joe, W4TV

On 7/5/2010 7:34 PM, The Smiths wrote:

>
> I'm sorry but I completely disagree with you. Apparently you have
> not used diversity mode, or you haven't enjoyed it with an AB - BA
> (or AB- B) Mix mode on. The point behind diversity is NOT to have one
> antenna in one ear and another in the other.. The purpose of
> Diversity is to enable the user to hear a signal from TWO different
> sources (Main and Sub Receiver with Horz/Vertical antennas) at the
> same time.
>
> If you've ever used Diversity on a weak signal, or on a station that
> is phasing from Horz. to vertical polarization (as they do coming
> over the ocean all the time), then you would know that the signal
> "SWIMS" from your left ear to your right ear. This effect is NOT
> desirable when the frequency of the swimming becomes constant. The
> effect in fact can cause one to feel like they are on a rocking
> boat. For this reason alone it is nice to be able to "add" the Sub
> (or Vertical phase) to the Main (Horz. phase) thereby canceling out
> the swimming effect on the listener. This allows for easy reception
> and a single signal that "fills" the ears with a constant audio even
> as the phase shifts from one polarity to the other. In the AB - B mix
> mode the user can still ascertain which antenna the signal is coming
> from because even though the both phases are filling both ears, there
> is a slight "leaning" effect to the signal in the right ear when
> phasing to the Sub receiver.
>
>
> Diversity mode has NOTHING to do with being forced to listen to 2
> signals in one ear or the other. In any case, if this is the effect
> you want, feel free to keep the mixer off. For others, like myself
> who may have a beverage antenna and a vertical set up, we would like
> not to have to feel like we're sitting on the high seas while
> listening to a signal. I completely understand why this other user in
> the group would request this feature. I was simply correcting Lyle
> that it was not available in the diversity mode as he suggested that
> it was. (or so it read)
>
> Again, this Mix mode option IS available for Sub mode only, but it
> has not been implemented in the Diversity mode yet. I'm only asking
> that the switch gets flipped to allow it to be turned on while in
> Diversity mode.
>
>
>
>
>
>> Date: Mon, 5 Jul 2010 17:43:29 -0400 From: [hidden email] To:
>> [hidden email] Subject: Re: [Elecraft] K3 Audio routing
>> question
>>
>>
>>> As you know, this is NOT working in the Diversity mode as this
>>> person wants to use it. It is ONLY available with SUB mode at the
>>> time. Perhaps you can Stress to Wayne that he should finally make
>>> it available for use when in Diversity...
>>
>> Making L-Mix-R function in diversity mode defeats the purpose of
>> diversity mode. Placing EITHER receiver in both ears during
>> diversity essentially disables diversity.
>>
>> I hate to be the one to say "don't waste the programming time" but
>> this is another of those "enhancements" that is a complete waste
>> of programmer time and does not make *ANY* practical sense.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>> On 7/5/2010 4:41 PM, The Smiths wrote:
>>>
>>> Lyle,
>>>
>>> As you know, this is NOT working in the Diversity mode as this
>>> person wants to use it. It is ONLY available with SUB mode at the
>>> time. Perhaps you can Stress to Wayne that he should finally make
>>> it available for use when in Diversity...
>>>
>>>> Date: Mon, 5 Jul 2010 13:15:53 -0700 From: [hidden email]
>>>> To: [hidden email] CC: [hidden email] Subject: Re:
>>>> [Elecraft] K3 Audio routing question
>>>>
>>>>
>>>>> Is there a way to get the audio from the sub receiver into
>>>>> both ears without external switching?
>>>>
>>>> Yes. See the firmware release notes and CONFIG:L-MIX-R
>>>>
>>>> 73,
>>>>
>>>> Lyle KK7P
>>
>> ______________________________________________________________
>> 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
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> with Hotmail.
> http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4

Peter Wollan-2

Re: K3 Audio routing question

I hesitate to jump in here, because there are some strong passions
running -- but I'm quite confused about what the disagreements are in
this thread. Isn't the whole point of diversity reception in the K3
that the receivers **are** synchronized to the same clock? And if
you're in diversity, and want to listen to just one receiver, can't
you make a macro to switch out to one receiver or the other?

Or is the disagreement about something else entirely?

Peter W0LLN
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W8JI

Re: K3 Audio routing question

In reply to this post by The Smiths

> I'm sorry but I completely disagree with you. Apparently you have not
> used diversity mode, or you haven't enjoyed it with an AB - BA (or AB- B)
> Mix mode on.

I've been using stereo diversity and other forms of diversity receiving
since around 1970 or so. After almost 40 years of using it, I can't imagine
why anyone would want to mix one channel into both ears unless they didn't
have the antenna spacing to actually produce true diversity. .

> The point behind diversity is NOT to have one antenna in one ear and
> another in the other.. The purpose of Diversity is to enable the user to
> hear a signal from TWO different sources (Main and Sub Receiver with
> Horz/Vertical antennas) at the same time.

The phase continually rotates in the phase relationship from one antenna to
another. The only exception to this is when the antenna are unable to
provide diversity, and act like a single antenna. So if you have the proper
configuartion to provide diversity, and you directly mix the signals, the
result will always be something between no change at all to MORE fading and
reduced S/N ratio. It will never be better without and equal or longer time
being worse.

> If you've ever used Diversity on a weak signal, or on a station that is
> phasing from Horz. to vertical polarization (as they do coming over the
> ocean all the time), then you would know that the signal "SWIMS" from your
> left ear to your right ear. This effect is NOT desirable when the
> frequency of the swimming becomes constant. The effect in fact can cause
> one to feel like they are on a rocking boat.

Your brain will probably get used to it, and eventually process it
correctly.

> For this reason alone it is nice to be able to "add" the Sub (or Vertical
> phase) to the Main (Horz. phase) thereby canceling out the swimming effect
> on the listener. This allows for easy reception and a single signal that
> "fills" the ears with a constant audio even as the phase shifts from one
> polarity to the other.
> In the AB - B mix mode the user can still ascertain which antenna the
> signal is coming from because even though the both phases are filling both
> ears, there is a slight "leaning" effect to the signal in the right ear
> when phasing to the Sub receiver.

If you add A to B in one ear, that channel will have reduced S/N and
increased fading at least 50% of the time or more. The other channel, being
just B, will be unaffected.

> Diversity mode has NOTHING to do with being forced to listen to 2 signals
> in one ear or the other. In any case, if this is the effect you want,
> feel free to keep the mixer off. For others, like myself who may have a
> beverage antenna and a vertical set up, we would like not to have to feel
> like we're sitting on the high seas while listening to a signal.
> I completely understand why this other user in the group would request
> this feature. I was simply correcting Lyle that it was not available in
> the diversity mode as he suggested that it was. (or so it read)
>
> Again, this Mix mode option IS available for Sub mode only, but it has not
> been implemented in the Diversity mode yet. I'm only asking that the
> switch gets flipped to allow it to be turned on while in Diversity mode.

I have no opinion one way or another on programming requests, but I do know
very well how diversity works and how the K3 works. The K3 has a stable
phase relationship from channel to channel (main to sub) on any given
frequency but the exact phase difference from main to sub changes as the
frequency is varied. You can hear this if you mix both channels into mono
and listen to background noise as you tune the VFO up and down the band.
What you will hear is peaks and nulls in background noise as the phase
rotates with the VFO setting. This is because you are changing the combined
antenna array PATTERN as the VFO is moved up or down the band. If you
directly mix two antennas with any significant spacing as processed through
the main and sub into one channel, be it one ear or both ears, you
absolutely will have a random changing antenna pattern as you tune the VFO.
Since the K3 has no controlled way to vary channel to channel phase, we
would have a random uncontrolled pattern null or nulls moving around in
different directions as the VFO knob is rotated.

Changing phase from channel to channel in the receiver is exactly like
mixing the two antennas together before they get to the rig and varying the
phase delay on one antenna prior to RF mixing. So when we mix A and B at
audio is like adding a noise canceller and mixing two channels with a random
spin of the knob. No difference at all. None....and this is etched in stone.
It is how phase meters like the old HP vector voltmeters work so it is a
well-established process.

The second issue is the arriving signals will have significant phase shift
from antenna to antenna that changes over time if the antennas are far
enough apart or enough different in polarization (a Beverage is vertically
polarized, as is a vertical antenna...so with a Beverage and vertical we
really have TWO verticals...not one vertical and one horizontal) and this
adds a random phase variation that can add or subtract signals depending on
the moment in time. If we really had two different polarization antennas,
like one responding to horizontal polarization and the other to vertical,
mixing would increase fading.

If that "feature" was added, it should be added with an ability to lock it
out. I would want it permanently disabled here so operators would not
accidentally turn it on. :-)

73 Tom

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Don Wilhelm-4

Re: K3 Audio routing question

In reply to this post by Peter Wollan-2

Peter,

Let me try - If one listens to only one receiver in both ears, there is
no diversity reception (one receiver cannot do diversity).
If both receivers are mixed in any one headphone, the result will be
cancellations in that headphone due to the varying effects from both
receivers. The best way to use diversity reception is to hear one
receiver in one ear and the other in the second ear, and let the brain
do the "deciphering".

Lyle has provided a means to allow the mixing requested. Whether it
will be beneficial to the person(s) requesting it or not remains to be
seen. You may use Lyle's mixing parameters and see for yourself if you
want.

The K3 receivers are the same, but they each use their own synthesizer -
that means they are not fully phased locked. The diversity comes from
having two antennas that are physically separated, and perhaps have
different polarizations.

73,
Don W3FPR

Peter Wollan wrote:

> I hesitate to jump in here, because there are some strong passions
> running -- but I'm quite confused about what the disagreements are in
> this thread. Isn't the whole point of diversity reception in the K3
> that the receivers **are** synchronized to the same clock? And if
> you're in diversity, and want to listen to just one receiver, can't
> you make a macro to switch out to one receiver or the other?
>
> Or is the disagreement about something else entirely?
>
> Peter W0LLN
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The Smiths

Re: K3 Audio routing question

In reply to this post by W8JI

When I have phase shifting between the two antennas I don't have Phase shifting in my audio Left and right. In that I mean, if I look at the voltage on the o'scope I do not see the signal coming out of my head phones phasing from positive voltage to a negative voltage in the inverse between the two headphone outputs (L/R).
Unlike AC where when one side swings negative, if you were to add the inverse you would cancel out the entire signal (as you guys keep saying is the case), this is not the case with the diversity reception here at my QTH (and no I don't live in the bermuda triangle). The phase is in the antenna reception.. Not the audio that we listen to. When my vertical is picking up a vertical phased signal it is very possible that my Horizontal antenna is not receiving any signal at all.. Therefore if I have Mix on so that the sub is placed in the Main's headphone I do not cancel out the audio in the both ears. I am simply adding AUDIO, not phase, to one side of my headphone or the other.

There is no "magic audio" or Voltage that is swinging in a negative polarity in my headphones from an antenna that is not receiving an opposite polarity signal. If that were the case than I would just build an automatic audio phase reverser and listen to my horizontal antenna as the signal phased into a vertical polarity. I would never need diversity reception in the first place. I could just flip the phase of the audio input to the receiver when I stopped hearing the signal on my horizontal antenna assuming it was now phased in the vertical field.

If you use Lyle's Utility based Mixer mode for Diversity (IE. Enter the code he gave you here on the reflector) you will hear that it keeps the signal stable as it travels from one antenna to the other. It doesn't cause the audio in both my headsets to cancel itself out. I've used it before (both with Lyle's code, and with another rigs, and mixing boards) and have NEVER had the canceling affect. I would urge you to at least try it and see for yourself before you continue to draw conclusions.

Now, if this defies all principals of electronics and audio, then so be it.. but I can tell you with certainty that mixing the two antenna phases in one headset makes for BOTH signals to be heard at the same time. So once again, I completely disagree with your reasoning not to implement it. Sorry, but we'll just have to agree to disagree..

The code already exists, as you have already seen by the fact that Lyle has already writing it, and given you the knowledge how to turn it on. The only missing key here is Wayne, or Eric's adding it to the Config menu.

Furthermore, there is no need to panic, if you don't want this feature on your rig, simply DON'T TURN IT ON.. This already exists for other modes, and if you haven't already figured out how to turn it on, than you needn't worry about it affecting your diversity mode reception as it already works.

I believe this should conclude this Post as I (the person that started this portion of the discussion) has nothing further to add.... I beg you not to let this drag this subject on for days.. That's NOT what this reflector is about. Thank you.

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Joe Subich, W4TV-4

Re: K3 Audio routing question

In reply to this post by Joe Subich, W4TV-4

> I'm not sure how your rig works, but with mine, when I have phase
> shifting between the two antennas I don't have Phase shifting in my
> audio Left and right. In that I mean, if I look at the spectrum
> analyzer/o'scope I do not see the signal coming out of my head phones
> phasing from positive voltage to a negative voltage in the inverse
> between the two headphone outputs.

When you have phase shifting between the antennas, the relative
audio phase between the two audio signals most certainly changes.

You can't see the phasing with an oscilloscope because you don't
have stable single tone signals to compare. The best chance of
seeing the changing phase relationship between the two signals is
to use a Lissijous display with one receiver driving the vertical
amplifier and the other driving the horizontal amplifier. You
quickly see the display morph from long narrow lines to wide
ellipses to short narrow lines and small ellipses as the relative
phase and signal levels between the receivers changes.

If you mix those two signals, the audio level will change from
zero when the two signals are the same level but out of phase
to +6dB when the two signals are in phase and at the same level.
Most of the time the mixed signal level will average around
the relative volume level with very strange frequency response
as the relative phase shifts with frequency within the passband.

> There is no "magic audio" or Voltage that is swinging in a negative
> polarity in my headphones from an antenna that is not receiving an
> opposite polarity signal.

You obviously do not understand the nature of time varying multi-
path signals. The whole point is that the effective path length
to each receive antenna changes constantly. At 14,000,000 Hz, the
transmission path (height of the ionosphere) for one of the two
receive antennas needs to change only 16 feet (5 meters) - or
put another way, the signal reaching one antenna needs to be
delayed only about 3 nanoseconds relative to the other antenna,
for a mixed signal to go from maximum volume (in phase) to nothing
at all (out of phase).

If you have separate speakers or earphones the apparent location
of the signal will move around the room but unless the signal
to BOTH receivers goes to zero, it won't disappear. With mixing,
a signal that would be "everywhere" in the stereo field would
disappear completely while signals that would be directly "between
the ears" would be at maximum loudness.

73,

... Joe, W4TV

On 7/5/2010 9:33 PM, The Smiths wrote:

>
>
> I'm not sure how your rig works, but with mine, when I have phase
> shifting between the two antennas I don't have Phase shifting in my
> audio Left and right. In that I mean, if I look at the spectrum
> analyzer/o'scope I do not see the signal coming out of my head phones
> phasing from positive voltage to a negative voltage in the inverse
> between the two headphone outputs. Unlike AC where when one side
> swings negative, if you were to add the inverse you would cancle out
> the entire signal, this is not the case with the diversity reception.
> The phase is in the antenna reception.. Not the audio that we listen
> to. When my vertical is picking up a vertical phased signal it is
> very possible that my Horizontal antenna is not receiving any signal
> at all.. Therefore if I have Mix on so that the sub is placed in the
> Main's headphone I do not cancel out the audio in the both ears.
> There is no "magic audio" or Voltage that is swinging in a negative
> polarity in my headphones from an antenna that is not receiving an
> opposite polarity signal. If that were the case than I would just
> build an audio phase reverser and listen to my horizontal antenna as
> the signal phased into a vertical polarity. I would never need
> diversity reception in the first place. I could just flip the phase
> of the audio input to the receiver when I stopped hearing the signal
> on my horizontal antenna assuming it was now phased in the vertical
> field.
>
> If you use Lyle's Utility based Mixer mode for Diversity (IE. Enter
> the code he gave you here on the reflector) you will hear that it
> keeps the signal stable as it travels from one antenna to the other.
> It doesn't cause the audio in both my headsets to cancel itself out.
> I've used it before (both with Lyle's code, and with another rig) and
> have NEVER had the canceling affect. I would urge you to at least try
> it and see for yourself.
>
> Now, if this defies all principals of electronics and audio, then so
> be it.. but I can tell you with certainty that mixing the two antenna
> phases in one headset makes for BOTH signals to be heard at the same
> time. So once again, I completely disagree with your reasoning not to
> implement it. Sorry, but we'll just have to agree to disagree..
>
> The code already exists, as you have already seen by the fact that
> Lyle has already writing it, and given you the knowledge how to turn
> it on. The only missing key here is Wayne, or Eric's adding it to
> the Config menu.
>
>
>
>> Date: Mon, 5 Jul 2010 20:29:55 -0400 From: [hidden email] To:
>> [hidden email] CC: [hidden email] Subject: Re:
>> [Elecraft] K3 Audio routing question
>>
>>
>>> I'm sorry but I completely disagree with you. Apparently you
>>> have not used diversity mode, or you haven't enjoyed it with an
>>> AB - BA (or AB- B) Mix mode on.
>>
>> I'm sorry, you're wrong. If you MIX the two audio sources instead
>> of hearing them "swim" from ear to ear, you will hear them FADE out
>> completely as the phase differences cause them to cancel. "Swim" is
>> the mind's interpretation of the difference in phase and amplitude
>> between the PATH taken by the two signals.
>>
>> What you accomplish by mixing is to undo all the benefits of
>> diversity. You have simply moved the point of phase cancellation
>> from the single antenna to the single headphone. You have gone to
>> the great expense of building/buying/installing a second antenna
>> and buying/installing a second, identical receiver so you can
>> simply combine two non-coherent audio sources instead of two
>> non-coherent RF sources.
>>
>> The only way one can "mix" the feeds from a diversity receive
>> system is to provide a voting/switching system that evaluates the
>> signal to noise ratio (in FM it's called "quieting") and selects
>> the "better" signal - not mixes the two.
>>
>>> Again, this Mix mode option IS available for Sub mode only, but
>>> it has not been implemented in the Diversity mode yet. I'm only
>>> asking that the switch gets flipped to allow it to be turned on
>>> while in Diversity mode.
>>
>> Mixing is appropriate when one has two completely different
>> signals. It is NOT appropriate when one has the same signal with a
>> randomly varying phase and amplitude difference. With two
>> independent signals there is no cancellation.
>>
>> Again, enabling L - MIX - R in diversity is to waste programming
>> resources on something that is not only useless but will actually
>> result in decreased performance.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>> On 7/5/2010 7:34 PM, The Smiths wrote:
>>>
>>> I'm sorry but I completely disagree with you. Apparently you
>>> have not used diversity mode, or you haven't enjoyed it with an
>>> AB - BA (or AB- B) Mix mode on. The point behind diversity is NOT
>>> to have one antenna in one ear and another in the other.. The
>>> purpose of Diversity is to enable the user to hear a signal from
>>> TWO different sources (Main and Sub Receiver with Horz/Vertical
>>> antennas) at the same time.
>>>
>>> If you've ever used Diversity on a weak signal, or on a station
>>> that is phasing from Horz. to vertical polarization (as they do
>>> coming over the ocean all the time), then you would know that the
>>> signal "SWIMS" from your left ear to your right ear. This effect
>>> is NOT desirable when the frequency of the swimming becomes
>>> constant. The effect in fact can cause one to feel like they are
>>> on a rocking boat. For this reason alone it is nice to be able to
>>> "add" the Sub (or Vertical phase) to the Main (Horz. phase)
>>> thereby canceling out the swimming effect on the listener. This
>>> allows for easy reception and a single signal that "fills" the
>>> ears with a constant audio even as the phase shifts from one
>>> polarity to the other. In the AB - B mix mode the user can still
>>> ascertain which antenna the signal is coming from because even
>>> though the both phases are filling both ears, there is a slight
>>> "leaning" effect to the signal in the right ear when phasing to
>>> the Sub receiver.
>>>
>>>
>>> Diversity mode has NOTHING to do with being forced to listen to
>>> 2 signals in one ear or the other. In any case, if this is the
>>> effect you want, feel free to keep the mixer off. For others,
>>> like myself who may have a beverage antenna and a vertical set
>>> up, we would like not to have to feel like we're sitting on the
>>> high seas while listening to a signal. I completely understand
>>> why this other user in the group would request this feature. I
>>> was simply correcting Lyle that it was not available in the
>>> diversity mode as he suggested that it was. (or so it read)
>>>
>>> Again, this Mix mode option IS available for Sub mode only, but
>>> it has not been implemented in the Diversity mode yet. I'm only
>>> asking that the switch gets flipped to allow it to be turned on
>>> while in Diversity mode.
>>>
>>>
>>>
>>>
>>>
>>>> Date: Mon, 5 Jul 2010 17:43:29 -0400 From: [hidden email]
>>>> To: [hidden email] Subject: Re: [Elecraft] K3 Audio
>>>> routing question
>>>>
>>>>
>>>>> As you know, this is NOT working in the Diversity mode as
>>>>> this person wants to use it. It is ONLY available with SUB
>>>>> mode at the time. Perhaps you can Stress to Wayne that he
>>>>> should finally make it available for use when in
>>>>> Diversity...
>>>>
>>>> Making L-Mix-R function in diversity mode defeats the purpose
>>>> of diversity mode. Placing EITHER receiver in both ears during
>>>> diversity essentially disables diversity.
>>>>
>>>> I hate to be the one to say "don't waste the programming time"
>>>> but this is another of those "enhancements" that is a complete
>>>> waste of programmer time and does not make *ANY* practical
>>>> sense.
>>>>
>>>> 73,
>>>>
>>>> ... Joe, W4TV
>>>>
>>>>
>>>> On 7/5/2010 4:41 PM, The Smiths wrote:
>>>>>
>>>>> Lyle,
>>>>>
>>>>> As you know, this is NOT working in the Diversity mode as
>>>>> this person wants to use it. It is ONLY available with SUB
>>>>> mode at the time. Perhaps you can Stress to Wayne that he
>>>>> should finally make it available for use when in
>>>>> Diversity...
>>>>>
>>>>>> Date: Mon, 5 Jul 2010 13:15:53 -0700 From:
>>>>>> [hidden email] To: [hidden email] CC:
>>>>>> [hidden email] Subject: Re: [Elecraft] K3 Audio
>>>>>> routing question
>>>>>>
>>>>>>
>>>>>>> Is there a way to get the audio from the sub receiver
>>>>>>> into both ears without external switching?
>>>>>>
>>>>>> Yes. See the firmware release notes and CONFIG:L-MIX-R
>>>>>>
>>>>>> 73,
>>>>>>
>>>>>> Lyle KK7P
>>>>
>>>> ______________________________________________________________
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>>>> mailto:[hidden email]
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>>>
>>>

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The Smiths

Re: K3 Audio routing question

Okay Joe,

Your point is very well taken.. I understand what you are saying very clearly. I have the scope, and I've set it to look at phase between the two channels. I guess I need to clarify something. When I'm in diversity mode I don't seem to have both signals on both antennas at the same time.

This is where we are having a problem communicating. I'm not going to disagree with your theory that the signals WOULD cancel out the stereo imaging if I were to push one phase onto the other. I believe this is true, and I know it for fact.

However, where I am having an issue is when my poor receiving Vertical antenna is NOT receiving a signal my Well receiving Horz antenna is, and then Some times reverse. I would like to be able to "mix" the main onto the sub, and the sub onto the main's earphone

For me, the need for the audio mixer is not to crush the stereo XY, but more to let me receive while in diversity mode BOTH of my antennas at the same time, and let the mixer route my audio to both headsets so as I don't have to listen to it fall from one over another.

Admittedly, I don't have the best "diversity" set up here at my QTH, so for me it's more important that I keep a constant signal in both ears rather than one at a time.

Now, just for the sake of it, I would like you to tune to a signal that you are having the phasing sound with in diversity mode. Then, go to the utility and enter in !BEFF; in the terminal window. I would then like you to email me back and let me know that you didn't hear BOTH of your antennas at the same time, in both ears. I would be interested to know if you get NO signal at all from the same very station you were just listening to in both ears. Or even a reduced signal level. From my experience I've never had a signal cancel on me, I've only had it double in loudness. I'm sorry, I know this goes against what we both agree on when it comes to XY phase, but it's just the way it is. Do it for yourself and stop thinking theory.. Try reality. (I don't mean that as an insult, but rather a practical challenge.)

Again, even if this was the worst idea, it's still not going to affect YOUR rig if you never turn it on. This isn't an argument.. I was merely backing up the reasoning that the other person made the request. So, other than your return email to me after you've completed my test, can we PLEASE end this thread? Were beating a dead horse.

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g0afh

Re: K3 Audio routing question

In reply to this post by Don Wilhelm-4

Hi Don,

Imagine a system with good isolation between antennae such as you can
achieve with long yagi's at VHF/UHF. In my left ear I have the main RX
with stations from the UK, in my right ear I have the sub RX and
stations from Europe. I have a QRM from another G in my left ear when I
am called by a weak station from Europe which I hear in my right ear. As
the antennae have nice patterns I can barley hear the QRM from the G on
the antenna pointing at Europe. Now I want to mute or attenuate the
audio from the main RX and listen to the audio from the sub RX in both
ears. I know this will not be diversity any more but I'd quite like the
filter controls to continue to affect both receivers without having to
press BSET. After I have worked the station I need to return to
diversity mode listening to both receivers again.

Diversity mode almost does what I want with both receivers locked
together, I just need to be able to select which audio I listen to at a
given time. I can easily make up a box to switch the audio but I would
have thought that what I want to do is not that uncommon.

Hope this makes more sense.
73
Ian
G0AFH

Don Wilhelm wrote:

> Diversity reception requires hearing both the main and the subRX, each
> with their own antenna.
> I do not understand why one would want to listen to only the subRX when
> doing diversity receive - it nullifies any benefit of diversity.
> Can you explain further, maybe there is something I am missing.
>
> 73,
> Don W3FPR
>
> The Smiths wrote:
>
>> Lyle,
>>
>> As you know, this is NOT working in the Diversity mode as this person wants to use it. It is ONLY available with SUB mode at the time. Perhaps you can Stress to Wayne that he should finally make it available for use when in Diversity...
>>
>>
>>
>>
> ______________________________________________________________
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gd0tep

Re: K3 Audio routing question

Yes... this is something I'd like to see as well....

In the RSGB/IARU 50mhz annual contest, the station here consists of 4 large
antenna systems and 4 receivers. It would be beneficial to me if I was able
to drop that down to 2 K3's!

73,
Andy
http://gd0tep.com

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of g0afh
Sent: 06 July 2010 08:26
To: [hidden email]; [hidden email]
Subject: Re: [Elecraft] K3 Audio routing question

Hi Don,

Imagine a system with good isolation between antennae such as you can
achieve with long yagi's at VHF/UHF. In my left ear I have the main RX with
stations from the UK, in my right ear I have the sub RX and stations from
Europe. I have a QRM from another G in my left ear when I am called by a
weak station from Europe which I hear in my right ear. As the antennae have
nice patterns I can barley hear the QRM from the G on the antenna pointing
at Europe. Now I want to mute or attenuate the audio from the main RX and
listen to the audio from the sub RX in both ears. I know this will not be
diversity any more but I'd quite like the filter controls to continue to
affect both receivers without having to press BSET. After I have worked the
station I need to return to diversity mode listening to both receivers
again.

Diversity mode almost does what I want with both receivers locked together,
I just need to be able to select which audio I listen to at a given time. I
can easily make up a box to switch the audio but I would have thought that
what I want to do is not that uncommon.

Hope this makes more sense.
73
Ian
G0AFH

Don Wilhelm wrote:

> Diversity reception requires hearing both the main and the subRX, each
> with their own antenna.
> I do not understand why one would want to listen to only the subRX
> when doing diversity receive - it nullifies any benefit of diversity.
> Can you explain further, maybe there is something I am missing.
>
> 73,
> Don W3FPR
>
> The Smiths wrote:
>
>> Lyle,
>>
>> As you know, this is NOT working in the Diversity mode as this person

wants to use it. It is ONLY available with SUB mode at the time. Perhaps
you can Stress to Wayne that he should finally make it available for use
when in Diversity...

>>
>>
>>
>>
> ______________________________________________________________
> Elecraft mailing list
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>
> This list hosted by: http://www.qsl.net Please help support this email
> list: http://www.qsl.net/donate.html
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Phil Salas

Re: K3 Audio routing question

In reply to this post by The Smiths

"...However, where I am having an issue is when my poor receiving Vertical
antenna is NOT receiving a signal my Well receiving Horz antenna is, and
then Some times reverse. I would like to be able to "mix" the main onto the
sub, and the sub onto the main's earphone.."

The only way this would work is to always mute the weaker side, and always
feed the strong side into both headphones. As stated by several others
here, true combining would not work because of the varying phase difference
between the main and diversity inputs.

We implemented combining for diversity digital (QAM) receivers back in my
microwave days at Rockwell. The IF combiner continuously rotated the phase
of the diversity receiver so as to keep the combined amplitude at a maximum.
This was not a trivial process. And, of course, both receivers were fed
with the same local oscillator. For analog receivers, we used a simple A/B
diversity switch where we switched to the stronger side when the signal we
were on was getting close to threshold and the other side had a better S/N.
Couldn't do this with digital signals since a simple switch would cause a
frame hit/re-sync. So the IF combiner was used for diversity reception in
our digital radios.

Phil - AD5X

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123