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Synthesizer Issue

Can someone please give me a summary of this synthesizer issue or a useful link so I can understand all this conversation about new boards. I have a three year old K-3 and a one year old sub-receiver. Do I need these boards? What would they do for me? An off-list reply is welcome since it appears I’m the only one who doesn’t know what’s going on. Thanks.

Jimmy, WA4ILO

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wayne burdick

Re: Synthesizer Issue

Administrator

Some users of the new synthesizer have also reported an improvement in the way diversity mode sounds. This is due to a change in the way the receivers are driven by the synths.

In diversity mode, as long as the main and sub crystal filter offsets are matched, both receivers are driven by the main synth (the sub synth is not used in this case). So, when the VFO is moved, the local oscillator phase relationship remains stable between the main and sub receivers.

With the original synths, moving the VFO even a small amount causes both the main and sub synths to be updated. Since they use separate LC oscillators, the phase relationship will change. The two will remain phase-locked to the reference, but the absolute value of the phase between the two synths will be some value between 0 and 180 degrees.

We'll add this to the FAQ.

73,
Wayne
N6KR

On Mar 2, 2015, at 6:10 PM, Walter Underwood <[hidden email]> wrote:

> Start with the FAQ here: http://www.elecraft.com/manual/KSYN3A%20FAQ-ver-C-2.pdf
>
> The original announcement on this list described it like this:
>
> The KSYN3A synthesizer module is a completely new design that improves on the original KSYN3 in several ways:
>
> ULTRA-LOW PHASE NOISE
> The KSYN3A significantly improves the K3's already excellent RX and TX phase noise at close carrier spacings. This in turn noticeably improves the K3's top performing close spaced Rx dynamic range, yielding even better weak signal detection in the presence of strong signals.
>
> FASTER CW BREAK-IN AND MORE ACCURATE CW ELEMENT TIMING
>
> EXCELLENT MECHANICAL STABILITY
> The KSYN3A is virtually immune to both physical vibration and magnetic coupling, and operates over a very wide temperature range.
>
> 600-METER COVERAGE
> The KSYN3A extends VFO tuning down to 100 kHz, with sensitivity gradually falling off below 450 kHz. Transmit output is as high as 1.0 mW for use with a suitable external amplifier. (Note: 600-m and below operation also requires the KBPF3 and KXV3 options.)
>
> wunder
> K6WRU
> CM87wj
> http://observer.wunderwood.org/
>
> On Mar 2, 2015, at 6:02 PM, James D. (Jimmy) Walker, Jr. via Elecraft <[hidden email]> wrote:
>
>> Can someone please give me a summary of this synthesizer issue or a useful link so I can understand all this conversation about new boards. I have a three year old K-3 and a one year old sub-receiver. Do I need these boards? What would they do for me? An off-list reply is welcome since it appears I’m the only one who doesn’t know what’s going on. Thanks.
>>
>> Jimmy, WA4ILO
>>
>> ______________________________________________________________
>> 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]
>
> ______________________________________________________________
> 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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riese-k3djc

Re: Synthesizer Issue

In reply to this post by Elecraft mailing list

Hi Wayne

with the new board and software up dates is there a new band or do you
just keep tuning below
the BC band,,,, if we ever get 600 meters the K3 would be a great and
only rig to have
coverage

Bob K3DJC

On Mon, 2 Mar 2015 18:21:50 -0800 Wayne Burdick <[hidden email]>
writes:

> Some users of the new synthesizer have also reported an improvement
> in the way diversity mode sounds. This is due to a change in the way
> the receivers are driven by the synths.
>
> In diversity mode, as long as the main and sub crystal filter
> offsets are matched, both receivers are driven by the main synth
> (the sub synth is not used in this case). So, when the VFO is moved,
> the local oscillator phase relationship remains stable between the
> main and sub receivers.
>
> With the original synths, moving the VFO even a small amount causes
> both the main and sub synths to be updated. Since they use separate
> LC oscillators, the phase relationship will change. The two will
> remain phase-locked to the reference, but the absolute value of the
> phase between the two synths will be some value between 0 and 180
> degrees.
>
> We'll add this to the FAQ.
>
> 73,
> Wayne
> N6KR

wayne burdick

Re: Synthesizer Issue

Administrator

Hi Bob,

The new frequency coverage is still part of the 160-meter band. If you need quick access to the 600-meter range (~475 kHz), you can use any of several different ways to get to it:

- the four per-band "quick memories" on 160 m

- the 100 general-purpose memories

- direct frequency entry

- a programmable function switch

As an example of the latter, you could create a K3 command macro using K3 Utility, such as:

FA00000475000;MD3;PA0;

This sets VFO A to 475 kHz, CW mode, with the preamp off. Of course you would also want to bring the signal in through RX ANT IN or XVTR IN, so the high-pass filter in the T/R switch is bypassed. Using XVTR IN requires setting CONFIG:KXV3 to TEST. We may provide a simpler way to do this in the future.

73,
Wayne
N6KR

On Mar 2, 2015, at 6:28 PM, <[hidden email]> wrote:

> Hi Wayne
>
> with the new board and software up dates is there a new band or do you
> just keep tuning below
> the BC band,,,, if we ever get 600 meters the K3 would be a great and
> only rig to have
> coverage
>
> Bob K3DJC
>
>
> On Mon, 2 Mar 2015 18:21:50 -0800 Wayne Burdick <[hidden email]>
> writes:
>> Some users of the new synthesizer have also reported an improvement
>> in the way diversity mode sounds. This is due to a change in the way
>> the receivers are driven by the synths.
>>
>> In diversity mode, as long as the main and sub crystal filter
>> offsets are matched, both receivers are driven by the main synth
>> (the sub synth is not used in this case). So, when the VFO is moved,
>> the local oscillator phase relationship remains stable between the
>> main and sub receivers.
>>
>> With the original synths, moving the VFO even a small amount causes
>> both the main and sub synths to be updated. Since they use separate
>> LC oscillators, the phase relationship will change. The two will
>> remain phase-locked to the reference, but the absolute value of the
>> phase between the two synths will be some value between 0 and 180
>> degrees.
>>
>> We'll add this to the FAQ.
>>
>> 73,
>> Wayne
>> N6KR
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Edward R Cole

Re: Synthesizer Issue

In reply to this post by Elecraft mailing list

I have several of the 100 memories programmed to 600m frequencies
using the K3 Memory Editor. To enter TEST mode I just Press-Hold
"MODE up". TX flashes to indicate its in TEST mode and Tx and Rx is
routed thru the XVTR connections.

73, Ed - KL7UW, WD2XSH/45
--------------------------
From: Wayne Burdick <[hidden email]>
To: <[hidden email]>
Cc: [hidden email]
Subject: Re: [Elecraft] Synthesizer Issue
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=us-ascii

Hi Bob,

The new frequency coverage is still part of the 160-meter band. If
you need quick access to the 600-meter range (~475 kHz), you can use
any of several different ways to get to it:

- the four per-band "quick memories" on 160 m

- the 100 general-purpose memories

- direct frequency entry

- a programmable function switch

As an example of the latter, you could create a K3 command macro
using K3 Utility, such as:

FA00000475000;MD3;PA0;

This sets VFO A to 475 kHz, CW mode, with the preamp off. Of course
you would also want to bring the signal in through RX ANT IN or XVTR
IN, so the high-pass filter in the T/R switch is bypassed. Using XVTR
IN requires setting CONFIG:KXV3 to TEST. We may provide a simpler way
to do this in the future.

73,
Wayne
N6KR

73, Ed - KL7UW
http://www.kl7uw.com
"Kits made by KL7UW"
Dubus Mag business:
[hidden email]

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Eric NO3M

Re: Synthesizer Issue

Press-Hold "MODE up" is to put the rig in TX TEST (ie. disable RF
output), not the same as CONFIG:KXV3=TEST. To get CONFIG:KXV3=TEST
either has to be done via the CONFIG menu or assigned as a toggle macro
to M1-M4 or PF1/2.

73 Eric NO3M

On 03/03/2015 02:30 AM, Edward R Cole wrote:
> To enter TEST mode I just Press-Hold "MODE up". TX flashes to
> indicate its in TEST mode and Tx and Rx is routed thru the XVTR
> connections.
>
> 73, Ed - KL7UW, WD2XSH/45

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Brendan Minish

Re: Synthesizer Issue

In reply to this post by wayne burdick

Wayne,

This IS a big improvement for us Diversity users, particularly when
using diversity to keep track of a pile of callers in a contest pileup.

With the Old synths since the phase relationship between the 2 vfos
would shift after TX the positioning of callers in the Image would alter
after each transmit operation, with the new Synths this no longer
happens.

The already very good Diversity mode has gotten much better with this
upgrade. I'd also suggest that folks who didn't take to diversity before
might wish to give it a second try.
For Diversity reception the RX antenna needs to be different than the TX
antenna (E.g a vertical and a beam, or a doublet ) you don't need a
dedicated RX antenna, it just needs to have different characteristics
than the main antenna. Physical separation &/or polarity differences
will also help.

For me, the price of the upgrade was worth it for the Diversity
improvements alone

73
Brendan EI6IZ

On Mon, 2015-03-02 at 18:21 -0800, Wayne Burdick wrote:

> Some users of the new synthesizer have also reported an improvement in the way diversity mode sounds. This is due to a change in the way the receivers are driven by the synths.
>
> In diversity mode, as long as the main and sub crystal filter offsets are matched, both receivers are driven by the main synth (the sub synth is not used in this case). So, when the VFO is moved, the local oscillator phase relationship remains stable between the main and sub receivers.
>
> With the original synths, moving the VFO even a small amount causes both the main and sub synths to be updated. Since they use separate LC oscillators, the phase relationship will change. The two will remain phase-locked to the reference, but the absolute value of the phase between the two synths will be some value between 0 and 180 degrees.
>
> We'll add this to the FAQ.
>
> 73,
> Wayne
> N6KR
>
>
>
> On Mar 2, 2015, at 6:10 PM, Walter Underwood <[hidden email]> wrote:
>
> > Start with the FAQ here: http://www.elecraft.com/manual/KSYN3A%20FAQ-ver-C-2.pdf
> >
> > The original announcement on this list described it like this:
> >
> > The KSYN3A synthesizer module is a completely new design that improves on the original KSYN3 in several ways:
> >
> > ULTRA-LOW PHASE NOISE
> > The KSYN3A significantly improves the K3's already excellent RX and TX phase noise at close carrier spacings. This in turn noticeably improves the K3's top performing close spaced Rx dynamic range, yielding even better weak signal detection in the presence of strong signals.
> >
> > FASTER CW BREAK-IN AND MORE ACCURATE CW ELEMENT TIMING
> >
> > EXCELLENT MECHANICAL STABILITY
> > The KSYN3A is virtually immune to both physical vibration and magnetic coupling, and operates over a very wide temperature range.
> >
> > 600-METER COVERAGE
> > The KSYN3A extends VFO tuning down to 100 kHz, with sensitivity gradually falling off below 450 kHz. Transmit output is as high as 1.0 mW for use with a suitable external amplifier. (Note: 600-m and below operation also requires the KBPF3 and KXV3 options.)
> >
> > wunder
> > K6WRU
> > CM87wj
> > http://observer.wunderwood.org/
> >
> > On Mar 2, 2015, at 6:02 PM, James D. (Jimmy) Walker, Jr. via Elecraft <[hidden email]> wrote:
> >
> >> Can someone please give me a summary of this synthesizer issue or a useful link so I can understand all this conversation about new boards. I have a three year old K-3 and a one year old sub-receiver. Do I need these boards? What would they do for me? An off-list reply is welcome since it appears I’m the only one who doesn’t know what’s going on. Thanks.
> >>
> >> Jimmy, WA4ILO
> >>
> >> ______________________________________________________________
> >> 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]
> >
> > ______________________________________________________________
> > 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]
>
> ______________________________________________________________
> 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]

--
73
Brendan EI6IZ

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GM4JJJ

Re: Synthesizer Issue

In reply to this post by wayne burdick

Wayne,

For folks that were using the two receivers for VHF EME polarity diversity reception over a wide bandwidth with MAP65 software, where they would have gain and phase matched preamps this must be an improvement for them.

I think it was not generally understood that the absolute value of the phase relationship of the receivers would change as the VFO was moved. The only person I know that is currently using his K3 for doing this is Ed KL7UW, so he may be interested in this.

73

David Anderson GM4JJJ

> On 3 Mar 2015, at 02:21, Wayne Burdick <[hidden email]> wrote:
>
> Some users of the new synthesizer have also reported an improvement in the way diversity mode sounds. This is due to a change in the way the receivers are driven by the synths.
>
> In diversity mode, as long as the main and sub crystal filter offsets are matched, both receivers are driven by the main synth (the sub synth is not used in this case). So, when the VFO is moved, the local oscillator phase relationship remains stable between the main and sub receivers.
>
> With the original synths, moving the VFO even a small amount causes both the main and sub synths to be updated. Since they use separate LC oscillators, the phase relationship will change. The two will remain phase-locked to the reference, but the absolute value of the phase between the two synths will be some value between 0 and 180 degrees.
>
> We'll add this to the FAQ.
>
> 73,
> Wayne
> N6KR
>
>
>
>> On Mar 2, 2015, at 6:10 PM, Walter Underwood <[hidden email]> wrote:
>>
>> Start with the FAQ here: http://www.elecraft.com/manual/KSYN3A%20FAQ-ver-C-2.pdf
>>
>> The original announcement on this list described it like this:
>>
>> The KSYN3A synthesizer module is a completely new design that improves on the original KSYN3 in several ways:
>>
>> ULTRA-LOW PHASE NOISE
>> The KSYN3A significantly improves the K3's already excellent RX and TX phase noise at close carrier spacings. This in turn noticeably improves the K3's top performing close spaced Rx dynamic range, yielding even better weak signal detection in the presence of strong signals.
>>
>> FASTER CW BREAK-IN AND MORE ACCURATE CW ELEMENT TIMING
>>
>> EXCELLENT MECHANICAL STABILITY
>> The KSYN3A is virtually immune to both physical vibration and magnetic coupling, and operates over a very wide temperature range.
>>
>> 600-METER COVERAGE
>> The KSYN3A extends VFO tuning down to 100 kHz, with sensitivity gradually falling off below 450 kHz. Transmit output is as high as 1.0 mW for use with a suitable external amplifier. (Note: 600-m and below operation also requires the KBPF3 and KXV3 options.)
>>
>> wunder
>> K6WRU
>> CM87wj
>> http://observer.wunderwood.org/
>>
>>> On Mar 2, 2015, at 6:02 PM, James D. (Jimmy) Walker, Jr. via Elecraft <[hidden email]> wrote:
>>>
>>> Can someone please give me a summary of this synthesizer issue or a useful link so I can understand all this conversation about new boards. I have a three year old K-3 and a one year old sub-receiver. Do I need these boards? What would they do for me? An off-list reply is welcome since it appears I’m the only one who doesn’t know what’s going on. Thanks.
>>>
>>> Jimmy, WA4ILO
>>>
>>> ______________________________________________________________
>>> 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]
>>
>> ______________________________________________________________
>> 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]
>
> ______________________________________________________________
> 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]

Edward R Cole

Re: Synthesizer Issue

In reply to this post by Elecraft mailing list

Dave, Wayne, others:

Improved synthesizer phase noise will improve eme similarly to any
weak-signal reception in presence of strong adjacent frequency interference.

Dual polarity diversity reception for eme requires software to
recover the polarity information. Two programs that I am aware of do
this: SM5BSZ's Linrad (Leif Asbrink) and MAP65 (Joe Tayor).

The software require two phase-locked receivers tuned to the same
frequency to produce two IQ outputs which are in-phase with each
other. Then the amplitude difference will produce polarity
information which can be displayed and the software can digitally
maximize SNR for best sensitivity (digitally aligns the output to the
polarity of the signal).

This does require both preamps, downconverters, receivers, and SDR's
to have a constant phase relationship. Both sw have calibration
routines to compensate the fixed phase difference in signal
paths. Gains need to be balanced, as well.

This is virtually impossible to achieve perfectly so the sw designers
added a utiltity to test the difference and add digital compensation
to remove this. My preamps are within less than a dB difference in
gain and the downconverter uses an identical ckt as does the
K3/KRX3. I use two LP-Pan for the SDR running on the 1st IF's of the
K3/KRX3 with them using a common LO. Finding a test signal to
perform the calibration is the hard part. Some eme signals are close
to 45-degree polarity that is needed for this procedure.

I will eventually upgrade my K3 with the new synth boards.

73, Ed - KL7UW

Date: Tue, 3 Mar 2015 22:21:13 +0000
From: David Anderson <[hidden email]>
To: Wayne Burdick <[hidden email]>
Cc: elecraft <[hidden email]>
Subject: Re: [Elecraft] Synthesizer Issue
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=utf-8

Wayne,

For folks that were using the two receivers for VHF EME polarity
diversity reception over a wide bandwidth with MAP65 software, where
they would have gain and phase matched preamps this must be an
improvement for them.

I think it was not generally understood that the absolute value of
the phase relationship of the receivers would change as the VFO was
moved. The only person I know that is currently using his K3 for
doing this is Ed KL7UW, so he may be interested in this.

73

David Anderson GM4JJJ

> On 3 Mar 2015, at 02:21, Wayne Burdick <[hidden email]> wrote:
>
> Some users of the new synthesizer have also reported an
improvement in the way diversity mode sounds. This is due to a change
in the way the receivers are driven by the synths.
>
> In diversity mode, as long as the main and sub crystal filter
offsets are matched, both receivers are driven by the main synth (the
sub synth is not used in this case). So, when the VFO is moved, the
local oscillator phase relationship remains stable between the main
and sub receivers.
>
> With the original synths, moving the VFO even a small amount
causes both the main and sub synths to be updated. Since they use
separate LC oscillators, the phase relationship will change. The two
will remain phase-locked to the reference, but the absolute value of
the phase between the two synths will be some value between 0 and 180 degrees.
>
> We'll add this to the FAQ.
>
> 73,
> Wayne
> N6KR

73, Ed - KL7UW
http://www.kl7uw.com
"Kits made by KL7UW"
Dubus Mag business:
[hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

Edward R Cole

Re: Synthesizer Issue

In reply to this post by Elecraft mailing list

In a couple e-mail exchanges off the reflector (with David) I
realized that I did not fully describe how diversity reception is
being used on eme (for adaptive dual-polarity reception). I know
this out of the area of most interest on this list so bear with me:

I forgot to say that using diversity reception with the K3 for eme,
the receiver (VFO-A) is set to a single frequency and not
moved. Typically on 2m-eme this is 144.125 MHz. The K3 is placed
into diversity reception and Tx SPLIT is engaged so that VFO-B
controls transmit frequency. Changing Tx frequency is done with
VFO-B which does not affect the diversity Rx.

This is used for digital eme modes so the K3 is run in DATA-A (USB)
mode to interface with a computer soundcard. Special SDR sw (MAP65)
is run on the computer which decodes received signals and generates
the transmit digital signal.

Receive tuning is done in the sw on the computer (VFO-A is not moved
from 144.125). The sw displays up to 90-KHz of the band (like a
panadaptor) and receive frequency is selected using the computer on
the digital frequency span display. So the receiver VFO is not moved
to tune within this sub-band and all frequencies preserve the same
phase relationship in both receivers in the K3. Rx tuning is done in
DSP and not in the K3.

Note: that I do not use the internal DSP (2nd IF) of the K3, but tap
off the 1st IF to two phase-locked LP-Pan to generate two IQ baseband
audio streams which are converted to digital by a special four-port
soundcard (M-Audio Delta-44).

This is quite different on how most use diversity Rx (where one tunes
VFO-A for different signals).

73, Ed - KL7UW
PS: as far as I am aware, I have the only dual-pol adaptive eme Rx
that utilizes the K3/KRX3 combo. Other stations use dual channel
SDR's such as the HB9DRI IQ+ receiver.

-----------------
Date: Tue, 3 Mar 2015 22:21:13 +0000
From: David Anderson <[hidden email]>
To: Wayne Burdick <[hidden email]>
Cc: elecraft <[hidden email]>
Subject: Re: [Elecraft] Synthesizer Issue
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=utf-8

Wayne,

For folks that were using the two receivers for VHF EME polarity
diversity reception over a wide bandwidth with MAP65 software, where
they would have gain and phase matched preamps this must be an
improvement for them.

I think it was not generally understood that the absolute value of
the phase relationship of the receivers would change as the VFO was
moved. The only person I know that is currently using his K3 for
doing this is Ed KL7UW, so he may be interested in this.

73

David Anderson GM4JJJ
snipped--------

> With the original synths, moving the VFO even a small amount
causes both the main and sub synths to be updated. Since they use
separate LC oscillators, the phase relationship will change. The two
will remain phase-locked to the reference, but the absolute value of
the phase between the two synths will be some value between 0 and 180 degrees.

> 73,
> Wayne
> N6KR

73, Ed - KL7UW
http://www.kl7uw.com
"Kits made by KL7UW"
Dubus Mag business:
[hidden email]

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