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Elecraft K4 now in Rob Sherwood's RX performance table

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wayne burdick

Elecraft K4 now in Rob Sherwood's RX performance table

Administrator

Sherwood has posted his measurements of the K4D's receiver performance in his table:

http://www.sherweng.com/table.html

We're quite pleased with his test results, which confirm that the K4/K4D is near the top of its class (direct-sampling SDRs). A K4HD would provide somewhat higher dynamic range for those stations in extreme signal environments, but the vast majority of operators will find that the K4/K4D more than meets their needs.

I'd like to highlight a few important items in Rob's chart.

First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB. Because it's a direct-sampling radio, this figure will hold at nearly all offsets from strong signals. Second is the block dynamic range number (128 dB), higher than almost every other "pure" SDR measured. Finally, there's the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable compared to all competing SDRs. This is an important number correlated with reciprocal mixing dynamic range (RMDR).

Taken together these demonstrate that the K4D will offer excellent performance in crowded band conditions.

Inevitably a question will arise regarding the chart position of the K4D relative to a couple of our other transceivers: the K3S and KX3. There's a bit of "apples to oranges" in both comparisons.

The K3S uses a superhet receiver architecture. The K4HD will provide a receive setting that emulates this superhet performance when and if it's needed. But the "pure" (direct sampling) method used by the K4 (all models) has many advantages. One is the elimination of artifacts associated with crystal filters. Another is that, as a pure SDR, the K4 has a far more flexible architecture. We'll be able to provide updates to the receive and transmit digital signal chains that cannot be added to a superhet like the K3S or its competitors.

The KX3 is another Elecraft radio high on Sherwood's chart. Its performance is excellent, especially at its price point. But its numbers relative to the K4 are somewhat misleading, as hinted at by Rob's footnotes. The KX3 uses a quadrature downsampling architecture, which digitally samples at baseband audio rather than at RF. This is ideal for a radio like the KX3 that has to have very low current drain for portable operations. The K4 uses a direct-samping architecture that requires a higher power digital signal chain, resulting in important benefits over quadrature downsampling including much higher and more consistent opposite sideband image suppression and 2nd-order intermod rejection. So the two are really designed for different applications.

Overall, this first independent test of the K4 validates the performance of our SDR architecture. Feel free to send us any further performance questions.

73,
Wayne
N6KR

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BRUCE WW8II

Re: Elecraft K4 now in Rob Sherwood's RX performance table

I LOVE my K3s

Bruce
WW8II

On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]> wrote:

> Sherwood has posted his measurements of the K4D's receiver performance in
> his table:
>
> http://www.sherweng.com/table.html
>
> We're quite pleased with his test results, which confirm that the K4/K4D
> is near the top of its class (direct-sampling SDRs). A K4HD would provide
> somewhat higher dynamic range for those stations in extreme signal
> environments, but the vast majority of operators will find that the K4/K4D
> more than meets their needs.
>
> I'd like to highlight a few important items in Rob's chart.
>
> First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
> Because it's a direct-sampling radio, this figure will hold at nearly all
> offsets from strong signals. Second is the block dynamic range number (128
> dB), higher than almost every other "pure" SDR measured. Finally, there's
> the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable
> compared to all competing SDRs. This is an important number correlated with
> reciprocal mixing dynamic range (RMDR).
>
> Taken together these demonstrate that the K4D will offer excellent
> performance in crowded band conditions.
>
> Inevitably a question will arise regarding the chart position of the K4D
> relative to a couple of our other transceivers: the K3S and KX3. There's a
> bit of "apples to oranges" in both comparisons.
>
> The K3S uses a superhet receiver architecture. The K4HD will provide a
> receive setting that emulates this superhet performance when and if it's
> needed. But the "pure" (direct sampling) method used by the K4 (all models)
> has many advantages. One is the elimination of artifacts associated with
> crystal filters. Another is that, as a pure SDR, the K4 has a far more
> flexible architecture. We'll be able to provide updates to the receive and
> transmit digital signal chains that cannot be added to a superhet like the
> K3S or its competitors.
>
> The KX3 is another Elecraft radio high on Sherwood's chart. Its
> performance is excellent, especially at its price point. But its numbers
> relative to the K4 are somewhat misleading, as hinted at by Rob's
> footnotes. The KX3 uses a quadrature downsampling architecture, which
> digitally samples at baseband audio rather than at RF. This is ideal for a
> radio like the KX3 that has to have very low current drain for portable
> operations. The K4 uses a direct-samping architecture that requires a
> higher power digital signal chain, resulting in important benefits over
> quadrature downsampling including much higher and more consistent opposite
> sideband image suppression and 2nd-order intermod rejection. So the two are
> really designed for different applications.
>
> Overall, this first independent test of the K4 validates the performance
> of our SDR architecture. Feel free to send us any further performance
> questions.
>
> 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]
>

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Henry Pollock - K4TMC

Re: Elecraft K4 now in Rob Sherwood's RX performance table

I Love my K3+(new syn)!

73,
Henry - K4TMC
(K3 #98)

On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]> wrote:

> I LOVE my K3s
>
> Bruce
> WW8II
>
> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]> wrote:
>
> > Sherwood has posted his measurements of the K4D's receiver performance in
> > his table:
> >
> > http://www.sherweng.com/table.html
> >
> > We're quite pleased with his test results, which confirm that the K4/K4D
> > is near the top of its class (direct-sampling SDRs). A K4HD would provide
> > somewhat higher dynamic range for those stations in extreme signal
> > environments, but the vast majority of operators will find that the
> K4/K4D
> > more than meets their needs.
> >
> > I'd like to highlight a few important items in Rob's chart.
> >
> > First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
> > Because it's a direct-sampling radio, this figure will hold at nearly all
> > offsets from strong signals. Second is the block dynamic range number
> (128
> > dB), higher than almost every other "pure" SDR measured. Finally, there's
> > the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable
> > compared to all competing SDRs. This is an important number correlated
> with
> > reciprocal mixing dynamic range (RMDR).
> >
> > Taken together these demonstrate that the K4D will offer excellent
> > performance in crowded band conditions.
> >
> > Inevitably a question will arise regarding the chart position of the K4D
> > relative to a couple of our other transceivers: the K3S and KX3. There's
> a
> > bit of "apples to oranges" in both comparisons.
> >
> > The K3S uses a superhet receiver architecture. The K4HD will provide a
> > receive setting that emulates this superhet performance when and if it's
> > needed. But the "pure" (direct sampling) method used by the K4 (all
> models)
> > has many advantages. One is the elimination of artifacts associated with
> > crystal filters. Another is that, as a pure SDR, the K4 has a far more
> > flexible architecture. We'll be able to provide updates to the receive
> and
> > transmit digital signal chains that cannot be added to a superhet like
> the
> > K3S or its competitors.
> >
> > The KX3 is another Elecraft radio high on Sherwood's chart. Its
> > performance is excellent, especially at its price point. But its numbers
> > relative to the K4 are somewhat misleading, as hinted at by Rob's
> > footnotes. The KX3 uses a quadrature downsampling architecture, which
> > digitally samples at baseband audio rather than at RF. This is ideal for
> a
> > radio like the KX3 that has to have very low current drain for portable
> > operations. The K4 uses a direct-samping architecture that requires a
> > higher power digital signal chain, resulting in important benefits over
> > quadrature downsampling including much higher and more consistent
> opposite
> > sideband image suppression and 2nd-order intermod rejection. So the two
> are
> > really designed for different applications.
> >
> > Overall, this first independent test of the K4 validates the performance
> > of our SDR architecture. Feel free to send us any further performance
> > questions.
> >
> > 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]
> >
> ______________________________________________________________
> 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

Re: Elecraft K4 now in Rob Sherwood's RX performance table

Congrats Wayne and team on the K4 evaluation.

The two other responses do somewhat beg the question about what happens to the K3s used market and pricing. Not a lot of K3s for sale unlike the trickle to flood of k3.

At one point, I thought people were hanging on to their K3s waiting for a K4 upgrade which might well still be valid but I also wonder if people will simply stay with the K3s as the performance is clearly great and forgo the flexibility an SDR rig brings.

Paul
W6PNG
www.nomadic.blog

> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <[hidden email]> wrote:
>
> I Love my K3+(new syn)!
>
> 73,
> Henry - K4TMC
> (K3 #98)
>
>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]> wrote:
>>
>> I LOVE my K3s
>>
>> Bruce
>> WW8II
>>
>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]> wrote:
>>>
>>> Sherwood has posted his measurements of the K4D's receiver performance in
>>> his table:
>>>
>>> http://www.sherweng.com/table.html
>>>
>>> We're quite pleased with his test results, which confirm that the K4/K4D
>>> is near the top of its class (direct-sampling SDRs). A K4HD would provide
>>> somewhat higher dynamic range for those stations in extreme signal
>>> environments, but the vast majority of operators will find that the
>> K4/K4D
>>> more than meets their needs.
>>>
>>> I'd like to highlight a few important items in Rob's chart.
>>>
>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
>>> Because it's a direct-sampling radio, this figure will hold at nearly all
>>> offsets from strong signals. Second is the block dynamic range number
>> (128
>>> dB), higher than almost every other "pure" SDR measured. Finally, there's
>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable
>>> compared to all competing SDRs. This is an important number correlated
>> with
>>> reciprocal mixing dynamic range (RMDR).
>>>
>>> Taken together these demonstrate that the K4D will offer excellent
>>> performance in crowded band conditions.
>>>
>>> Inevitably a question will arise regarding the chart position of the K4D
>>> relative to a couple of our other transceivers: the K3S and KX3. There's
>> a
>>> bit of "apples to oranges" in both comparisons.
>>>
>>> The K3S uses a superhet receiver architecture. The K4HD will provide a
>>> receive setting that emulates this superhet performance when and if it's
>>> needed. But the "pure" (direct sampling) method used by the K4 (all
>> models)
>>> has many advantages. One is the elimination of artifacts associated with
>>> crystal filters. Another is that, as a pure SDR, the K4 has a far more
>>> flexible architecture. We'll be able to provide updates to the receive
>> and
>>> transmit digital signal chains that cannot be added to a superhet like
>> the
>>> K3S or its competitors.
>>>
>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
>>> performance is excellent, especially at its price point. But its numbers
>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
>>> footnotes. The KX3 uses a quadrature downsampling architecture, which
>>> digitally samples at baseband audio rather than at RF. This is ideal for
>> a
>>> radio like the KX3 that has to have very low current drain for portable
>>> operations. The K4 uses a direct-samping architecture that requires a
>>> higher power digital signal chain, resulting in important benefits over
>>> quadrature downsampling including much higher and more consistent
>> opposite
>>> sideband image suppression and 2nd-order intermod rejection. So the two
>> are
>>> really designed for different applications.
>>>
>>> Overall, this first independent test of the K4 validates the performance
>>> of our SDR architecture. Feel free to send us any further performance
>>> questions.
>>>
>>> 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]
>>>
>> ______________________________________________________________
>> 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]

wayne burdick

Re: Elecraft K4 now in Rob Sherwood's RX performance table

Administrator

Hi Paul,

While the decision is of course highly individual, there are many good reasons to upgrade to the K4.

Most obvious among them: the K4’s quantum leap in user interface. Second is perhaps the expansion of digital audio interfaces, including HDMI video, multiple USB ports, and ethernet.

The K4 also has unlimited expansion capability, both in software and hardware, to adapt to future needs. The HDR and transverter modules are only two examples. The ADCs and DAC are also located on small, easily upgraded modules, ready for whatever exotic technologies the future may bring. The internal main CPU is also in an industry standard form-factor so it can be easily upgraded.

Wayne
N6KR

----
elecraft.com

> On May 28, 2021, at 10:55 AM, Paul GACEK via Elecraft <[hidden email]> wrote:
>
> Congrats Wayne and team on the K4 evaluation.
>
> The two other responses do somewhat beg the question about what happens to the K3s used market and pricing. Not a lot of K3s for sale unlike the trickle to flood of k3.
>
> At one point, I thought people were hanging on to their K3s waiting for a K4 upgrade which might well still be valid but I also wonder if people will simply stay with the K3s as the performance is clearly great and forgo the flexibility an SDR rig brings.
>
> Paul
> W6PNG
> www.nomadic.blog
>
>> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <[hidden email]> wrote:
>>
>> I Love my K3+(new syn)!
>>
>> 73,
>> Henry - K4TMC
>> (K3 #98)
>>
>>>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]> wrote:
>>>
>>> I LOVE my K3s
>>>
>>> Bruce
>>> WW8II
>>>
>>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]> wrote:
>>>>
>>>> Sherwood has posted his measurements of the K4D's receiver performance in
>>>> his table:
>>>>
>>>> http://www.sherweng.com/table.html
>>>>
>>>> We're quite pleased with his test results, which confirm that the K4/K4D
>>>> is near the top of its class (direct-sampling SDRs). A K4HD would provide
>>>> somewhat higher dynamic range for those stations in extreme signal
>>>> environments, but the vast majority of operators will find that the
>>> K4/K4D
>>>> more than meets their needs.
>>>>
>>>> I'd like to highlight a few important items in Rob's chart.
>>>>
>>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
>>>> Because it's a direct-sampling radio, this figure will hold at nearly all
>>>> offsets from strong signals. Second is the block dynamic range number
>>> (128
>>>> dB), higher than almost every other "pure" SDR measured. Finally, there's
>>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable
>>>> compared to all competing SDRs. This is an important number correlated
>>> with
>>>> reciprocal mixing dynamic range (RMDR).
>>>>
>>>> Taken together these demonstrate that the K4D will offer excellent
>>>> performance in crowded band conditions.
>>>>
>>>> Inevitably a question will arise regarding the chart position of the K4D
>>>> relative to a couple of our other transceivers: the K3S and KX3. There's
>>> a
>>>> bit of "apples to oranges" in both comparisons.
>>>>
>>>> The K3S uses a superhet receiver architecture. The K4HD will provide a
>>>> receive setting that emulates this superhet performance when and if it's
>>>> needed. But the "pure" (direct sampling) method used by the K4 (all
>>> models)
>>>> has many advantages. One is the elimination of artifacts associated with
>>>> crystal filters. Another is that, as a pure SDR, the K4 has a far more
>>>> flexible architecture. We'll be able to provide updates to the receive
>>> and
>>>> transmit digital signal chains that cannot be added to a superhet like
>>> the
>>>> K3S or its competitors.
>>>>
>>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
>>>> performance is excellent, especially at its price point. But its numbers
>>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
>>>> footnotes. The KX3 uses a quadrature downsampling architecture, which
>>>> digitally samples at baseband audio rather than at RF. This is ideal for
>>> a
>>>> radio like the KX3 that has to have very low current drain for portable
>>>> operations. The K4 uses a direct-samping architecture that requires a
>>>> higher power digital signal chain, resulting in important benefits over
>>>> quadrature downsampling including much higher and more consistent
>>> opposite
>>>> sideband image suppression and 2nd-order intermod rejection. So the two
>>> are
>>>> really designed for different applications.
>>>>
>>>> Overall, this first independent test of the K4 validates the performance
>>>> of our SDR architecture. Feel free to send us any further performance
>>>> questions.
>>>>
>>>> 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]
>>>>
>>> ______________________________________________________________
>>> 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]

Bill Frantz

Re: Elecraft K4 now in Rob Sherwood's RX performance table

For me, the big draw is remote operation with a panadapter.
Currently I live a mile from my radio, which makes getting on
the air a small expedition, so I need to coordinate with my
wife. She feels better if I'm handy to help with whatever comes up.

73 Bill AE6JV

On 5/28/21 at 2:16 PM, [hidden email] (Wayne Burdick) wrote:

>While the decision is of course highly individual, there are
>many good reasons to upgrade to the K4.
-----------------------------------------------------------------------
Bill Frantz | Since the IBM Selectric, keyboards have gotten
408-348-7900 | steadily worse. Now we have touchscreen keyboards.
www.pwpconsult.com | Can we make something even worse?

______________________________________________________________
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David Gilbert-2

Re: Elecraft K4 now in Rob Sherwood's RX performance table

In reply to this post by Elecraft mailing list

I have a K3 with the new synths and nothing in the Sherwood data or
Wayne's post gives me any reason to switch to a K4, especially given the
cost to do so. Bells and whistles are completely secondary for me
compared with basic performance, and I still think that abandoning the
K3s was a mistake.

73,
Dave AB7E

On 5/28/2021 10:55 AM, Paul GACEK via Elecraft wrote:

> Congrats Wayne and team on the K4 evaluation.
>
> The two other responses do somewhat beg the question about what happens to the K3s used market and pricing. Not a lot of K3s for sale unlike the trickle to flood of k3.
>
> At one point, I thought people were hanging on to their K3s waiting for a K4 upgrade which might well still be valid but I also wonder if people will simply stay with the K3s as the performance is clearly great and forgo the flexibility an SDR rig brings.
>
> Paul
> W6PNG
> www.nomadic.blog
>
>> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <[hidden email]> wrote:
>>
>> I Love my K3+(new syn)!
>>
>> 73,
>> Henry - K4TMC
>> (K3 #98)
>>
>>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]> wrote:
>>>
>>> I LOVE my K3s
>>>
>>> Bruce
>>> WW8II
>>>
>>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]> wrote:
>>>>
>>>> Sherwood has posted his measurements of the K4D's receiver performance in
>>>> his table:
>>>>
>>>> http://www.sherweng.com/table.html
>>>>
>>>> We're quite pleased with his test results, which confirm that the K4/K4D
>>>> is near the top of its class (direct-sampling SDRs). A K4HD would provide
>>>> somewhat higher dynamic range for those stations in extreme signal
>>>> environments, but the vast majority of operators will find that the
>>> K4/K4D
>>>> more than meets their needs.
>>>>
>>>> I'd like to highlight a few important items in Rob's chart.
>>>>
>>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
>>>> Because it's a direct-sampling radio, this figure will hold at nearly all
>>>> offsets from strong signals. Second is the block dynamic range number
>>> (128
>>>> dB), higher than almost every other "pure" SDR measured. Finally, there's
>>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very favorable
>>>> compared to all competing SDRs. This is an important number correlated
>>> with
>>>> reciprocal mixing dynamic range (RMDR).
>>>>
>>>> Taken together these demonstrate that the K4D will offer excellent
>>>> performance in crowded band conditions.
>>>>
>>>> Inevitably a question will arise regarding the chart position of the K4D
>>>> relative to a couple of our other transceivers: the K3S and KX3. There's
>>> a
>>>> bit of "apples to oranges" in both comparisons.
>>>>
>>>> The K3S uses a superhet receiver architecture. The K4HD will provide a
>>>> receive setting that emulates this superhet performance when and if it's
>>>> needed. But the "pure" (direct sampling) method used by the K4 (all
>>> models)
>>>> has many advantages. One is the elimination of artifacts associated with
>>>> crystal filters. Another is that, as a pure SDR, the K4 has a far more
>>>> flexible architecture. We'll be able to provide updates to the receive
>>> and
>>>> transmit digital signal chains that cannot be added to a superhet like
>>> the
>>>> K3S or its competitors.
>>>>
>>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
>>>> performance is excellent, especially at its price point. But its numbers
>>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
>>>> footnotes. The KX3 uses a quadrature downsampling architecture, which
>>>> digitally samples at baseband audio rather than at RF. This is ideal for
>>> a
>>>> radio like the KX3 that has to have very low current drain for portable
>>>> operations. The K4 uses a direct-samping architecture that requires a
>>>> higher power digital signal chain, resulting in important benefits over
>>>> quadrature downsampling including much higher and more consistent
>>> opposite
>>>> sideband image suppression and 2nd-order intermod rejection. So the two
>>> are
>>>> really designed for different applications.
>>>>
>>>> Overall, this first independent test of the K4 validates the performance
>>>> of our SDR architecture. Feel free to send us any further performance
>>>> questions.
>>>>
>>>> 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]
>>>>
>>> ______________________________________________________________
>>> 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]

Ken Widelitz-2

Re: Elecraft K4 now in Rob Sherwood's RX performance table

Hi Dave,

I am remoting my VY2TT station. Unfortunately it didn't happen before the
Pandemic. For me, the most difficult challenge was remoting the panadapter.
K4 = problem solved. Anyone anywhere with a *tablet* and internet can have
a virtual K4 at their fingertips. As great a radio as it is, the K3s can't
do that.

73, Ken, K6LA / VY2TT

On Fri, May 28, 2021 at 1:09 PM David Gilbert <[hidden email]> wrote:

>
> I have a K3 with the new synths and nothing in the Sherwood data or
> Wayne's post gives me any reason to switch to a K4, especially given the
> cost to do so. Bells and whistles are completely secondary for me
> compared with basic performance, and I still think that abandoning the
> K3s was a mistake.
>
> 73,
> Dave AB7E
>
>
> On 5/28/2021 10:55 AM, Paul GACEK via Elecraft wrote:
> > Congrats Wayne and team on the K4 evaluation.
> >
> > The two other responses do somewhat beg the question about what happens
> to the K3s used market and pricing. Not a lot of K3s for sale unlike the
> trickle to flood of k3.
> >
> > At one point, I thought people were hanging on to their K3s waiting for
> a K4 upgrade which might well still be valid but I also wonder if people
> will simply stay with the K3s as the performance is clearly great and forgo
> the flexibility an SDR rig brings.
> >
> > Paul
> > W6PNG
> > www.nomadic.blog
> >
> >> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <[hidden email]>
> wrote:
> >>
> >> I Love my K3+(new syn)!
> >>
> >> 73,
> >> Henry - K4TMC
> >> (K3 #98)
> >>
> >>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]> wrote:
> >>>
> >>> I LOVE my K3s
> >>>
> >>> Bruce
> >>> WW8II
> >>>
> >>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]>
> wrote:
> >>>>
> >>>> Sherwood has posted his measurements of the K4D's receiver
> performance in
> >>>> his table:
> >>>>
> >>>> http://www.sherweng.com/table.html
> >>>>
> >>>> We're quite pleased with his test results, which confirm that the
> K4/K4D
> >>>> is near the top of its class (direct-sampling SDRs). A K4HD would
> provide
> >>>> somewhat higher dynamic range for those stations in extreme signal
> >>>> environments, but the vast majority of operators will find that the
> >>> K4/K4D
> >>>> more than meets their needs.
> >>>>
> >>>> I'd like to highlight a few important items in Rob's chart.
> >>>>
> >>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101 dB.
> >>>> Because it's a direct-sampling radio, this figure will hold at nearly
> all
> >>>> offsets from strong signals. Second is the block dynamic range number
> >>> (128
> >>>> dB), higher than almost every other "pure" SDR measured. Finally,
> there's
> >>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very
> favorable
> >>>> compared to all competing SDRs. This is an important number correlated
> >>> with
> >>>> reciprocal mixing dynamic range (RMDR).
> >>>>
> >>>> Taken together these demonstrate that the K4D will offer excellent
> >>>> performance in crowded band conditions.
> >>>>
> >>>> Inevitably a question will arise regarding the chart position of the
> K4D
> >>>> relative to a couple of our other transceivers: the K3S and KX3.
> There's
> >>> a
> >>>> bit of "apples to oranges" in both comparisons.
> >>>>
> >>>> The K3S uses a superhet receiver architecture. The K4HD will provide a
> >>>> receive setting that emulates this superhet performance when and if
> it's
> >>>> needed. But the "pure" (direct sampling) method used by the K4 (all
> >>> models)
> >>>> has many advantages. One is the elimination of artifacts associated
> with
> >>>> crystal filters. Another is that, as a pure SDR, the K4 has a far more
> >>>> flexible architecture. We'll be able to provide updates to the receive
> >>> and
> >>>> transmit digital signal chains that cannot be added to a superhet like
> >>> the
> >>>> K3S or its competitors.
> >>>>
> >>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
> >>>> performance is excellent, especially at its price point. But its
> numbers
> >>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
> >>>> footnotes. The KX3 uses a quadrature downsampling architecture, which
> >>>> digitally samples at baseband audio rather than at RF. This is ideal
> for
> >>> a
> >>>> radio like the KX3 that has to have very low current drain for
> portable
> >>>> operations. The K4 uses a direct-samping architecture that requires a
> >>>> higher power digital signal chain, resulting in important benefits
> over
> >>>> quadrature downsampling including much higher and more consistent
> >>> opposite
> >>>> sideband image suppression and 2nd-order intermod rejection. So the
> two
> >>> are
> >>>> really designed for different applications.
> >>>>
> >>>> Overall, this first independent test of the K4 validates the
> performance
> >>>> of our SDR architecture. Feel free to send us any further performance
> >>>> questions.
> >>>>
> >>>> 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]
> >>>>
> >>> ______________________________________________________________
> >>> 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]
>
> ______________________________________________________________
> 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]

Robert Sands

Re: Elecraft K4 now in Rob Sherwood's RX performance table

I used to be a spec chaser but now I am a "feature appreciator" looking
forward to K4!
Bob K7VO

On Fri, May 28, 2021, 1:46 PM Ken Widelitz <[hidden email]> wrote:

> Hi Dave,
>
> I am remoting my VY2TT station. Unfortunately it didn't happen before the
> Pandemic. For me, the most difficult challenge was remoting the panadapter.
> K4 = problem solved. Anyone anywhere with a *tablet* and internet can have
> a virtual K4 at their fingertips. As great a radio as it is, the K3s can't
> do that.
>
> 73, Ken, K6LA / VY2TT
>
> On Fri, May 28, 2021 at 1:09 PM David Gilbert <[hidden email]> wrote:
>
> >
> > I have a K3 with the new synths and nothing in the Sherwood data or
> > Wayne's post gives me any reason to switch to a K4, especially given the
> > cost to do so. Bells and whistles are completely secondary for me
> > compared with basic performance, and I still think that abandoning the
> > K3s was a mistake.
> >
> > 73,
> > Dave AB7E
> >
> >
> > On 5/28/2021 10:55 AM, Paul GACEK via Elecraft wrote:
> > > Congrats Wayne and team on the K4 evaluation.
> > >
> > > The two other responses do somewhat beg the question about what happens
> > to the K3s used market and pricing. Not a lot of K3s for sale unlike the
> > trickle to flood of k3.
> > >
> > > At one point, I thought people were hanging on to their K3s waiting for
> > a K4 upgrade which might well still be valid but I also wonder if people
> > will simply stay with the K3s as the performance is clearly great and
> forgo
> > the flexibility an SDR rig brings.
> > >
> > > Paul
> > > W6PNG
> > > www.nomadic.blog
> > >
> > >> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <
> [hidden email]>
> > wrote:
> > >>
> > >> I Love my K3+(new syn)!
> > >>
> > >> 73,
> > >> Henry - K4TMC
> > >> (K3 #98)
> > >>
> > >>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]>
> wrote:
> > >>>
> > >>> I LOVE my K3s
> > >>>
> > >>> Bruce
> > >>> WW8II
> > >>>
> > >>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]>
> > wrote:
> > >>>>
> > >>>> Sherwood has posted his measurements of the K4D's receiver
> > performance in
> > >>>> his table:
> > >>>>
> > >>>> http://www.sherweng.com/table.html
> > >>>>
> > >>>> We're quite pleased with his test results, which confirm that the
> > K4/K4D
> > >>>> is near the top of its class (direct-sampling SDRs). A K4HD would
> > provide
> > >>>> somewhat higher dynamic range for those stations in extreme signal
> > >>>> environments, but the vast majority of operators will find that the
> > >>> K4/K4D
> > >>>> more than meets their needs.
> > >>>>
> > >>>> I'd like to highlight a few important items in Rob's chart.
> > >>>>
> > >>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101
> dB.
> > >>>> Because it's a direct-sampling radio, this figure will hold at
> nearly
> > all
> > >>>> offsets from strong signals. Second is the block dynamic range
> number
> > >>> (128
> > >>>> dB), higher than almost every other "pure" SDR measured. Finally,
> > there's
> > >>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very
> > favorable
> > >>>> compared to all competing SDRs. This is an important number
> correlated
> > >>> with
> > >>>> reciprocal mixing dynamic range (RMDR).
> > >>>>
> > >>>> Taken together these demonstrate that the K4D will offer excellent
> > >>>> performance in crowded band conditions.
> > >>>>
> > >>>> Inevitably a question will arise regarding the chart position of the
> > K4D
> > >>>> relative to a couple of our other transceivers: the K3S and KX3.
> > There's
> > >>> a
> > >>>> bit of "apples to oranges" in both comparisons.
> > >>>>
> > >>>> The K3S uses a superhet receiver architecture. The K4HD will
> provide a
> > >>>> receive setting that emulates this superhet performance when and if
> > it's
> > >>>> needed. But the "pure" (direct sampling) method used by the K4 (all
> > >>> models)
> > >>>> has many advantages. One is the elimination of artifacts associated
> > with
> > >>>> crystal filters. Another is that, as a pure SDR, the K4 has a far
> more
> > >>>> flexible architecture. We'll be able to provide updates to the
> receive
> > >>> and
> > >>>> transmit digital signal chains that cannot be added to a superhet
> like
> > >>> the
> > >>>> K3S or its competitors.
> > >>>>
> > >>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
> > >>>> performance is excellent, especially at its price point. But its
> > numbers
> > >>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
> > >>>> footnotes. The KX3 uses a quadrature downsampling architecture,
> which
> > >>>> digitally samples at baseband audio rather than at RF. This is ideal
> > for
> > >>> a
> > >>>> radio like the KX3 that has to have very low current drain for
> > portable
> > >>>> operations. The K4 uses a direct-samping architecture that requires
> a
> > >>>> higher power digital signal chain, resulting in important benefits
> > over
> > >>>> quadrature downsampling including much higher and more consistent
> > >>> opposite
> > >>>> sideband image suppression and 2nd-order intermod rejection. So the
> > two
> > >>> are
> > >>>> really designed for different applications.
> > >>>>
> > >>>> Overall, this first independent test of the K4 validates the
> > performance
> > >>>> of our SDR architecture. Feel free to send us any further
> performance
> > >>>> questions.
> > >>>>
> > >>>> 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]
> > >>>>
> > >>> ______________________________________________________________
> > >>> 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]
> >
> > ______________________________________________________________
> > 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]

Robert Sands
K7VO
Olympia, WA

Elecraft mailing list

Re: Elecraft K4 now in Rob Sherwood's RX performance table

I admit that I am a technology chaser. My current rigs offer all the features I use as I am not
very much of a demanding operator. But, I love technology and there is this thing
inside of me that says I need to have the latest of everything, always the latest iPhone,
the latest iMac, the latest iPad, and so on. Cost is not an issue, it does not get in the way
of my thirst for technology.

That, and that only, would be the reason I buy the K4 of I ever do decide to do that.

From an operating standpoint, I don’t think I use any features that are more of an edge
than my rig back in my novice days (Eico 720 transmitter, HQ-170AC receiver). I admit
to be a ham operator that does not challenge the “best” of the operating envelope.

73, phil, K7PEH

> On May 28, 2021, at 4:57 PM, Robert Sands <[hidden email]> wrote:
>
> I used to be a spec chaser but now I am a "feature appreciator" looking
> forward to K4!
> Bob K7VO
>
> On Fri, May 28, 2021, 1:46 PM Ken Widelitz <[hidden email]> wrote:
>
>> Hi Dave,
>>
>> I am remoting my VY2TT station. Unfortunately it didn't happen before the
>> Pandemic. For me, the most difficult challenge was remoting the panadapter.
>> K4 = problem solved. Anyone anywhere with a *tablet* and internet can have
>> a virtual K4 at their fingertips. As great a radio as it is, the K3s can't
>> do that.
>>
>> 73, Ken, K6LA / VY2TT
>>
>> On Fri, May 28, 2021 at 1:09 PM David Gilbert <[hidden email]> wrote:
>>
>>>
>>> I have a K3 with the new synths and nothing in the Sherwood data or
>>> Wayne's post gives me any reason to switch to a K4, especially given the
>>> cost to do so. Bells and whistles are completely secondary for me
>>> compared with basic performance, and I still think that abandoning the
>>> K3s was a mistake.
>>>
>>> 73,
>>> Dave AB7E
>>>
>>>
>>> On 5/28/2021 10:55 AM, Paul GACEK via Elecraft wrote:
>>>> Congrats Wayne and team on the K4 evaluation.
>>>>
>>>> The two other responses do somewhat beg the question about what happens
>>> to the K3s used market and pricing. Not a lot of K3s for sale unlike the
>>> trickle to flood of k3.
>>>>
>>>> At one point, I thought people were hanging on to their K3s waiting for
>>> a K4 upgrade which might well still be valid but I also wonder if people
>>> will simply stay with the K3s as the performance is clearly great and
>> forgo
>>> the flexibility an SDR rig brings.
>>>>
>>>> Paul
>>>> W6PNG
>>>> www.nomadic.blog
>>>>
>>>>> On May 28, 2021, at 10:32 AM, Henry Pollock - K4TMC <
>> [hidden email]>
>>> wrote:
>>>>>
>>>>> I Love my K3+(new syn)!
>>>>>
>>>>> 73,
>>>>> Henry - K4TMC
>>>>> (K3 #98)
>>>>>
>>>>>> On Fri, May 28, 2021 at 1:22 PM BRUCE WW8II <[hidden email]>
>> wrote:
>>>>>>
>>>>>> I LOVE my K3s
>>>>>>
>>>>>> Bruce
>>>>>> WW8II
>>>>>>
>>>>>>> On Fri, May 28, 2021 at 12:31 PM Wayne Burdick <[hidden email]>
>>> wrote:
>>>>>>>
>>>>>>> Sherwood has posted his measurements of the K4D's receiver
>>> performance in
>>>>>>> his table:
>>>>>>>
>>>>>>> http://www.sherweng.com/table.html
>>>>>>>
>>>>>>> We're quite pleased with his test results, which confirm that the
>>> K4/K4D
>>>>>>> is near the top of its class (direct-sampling SDRs). A K4HD would
>>> provide
>>>>>>> somewhat higher dynamic range for those stations in extreme signal
>>>>>>> environments, but the vast majority of operators will find that the
>>>>>> K4/K4D
>>>>>>> more than meets their needs.
>>>>>>>
>>>>>>> I'd like to highlight a few important items in Rob's chart.
>>>>>>>
>>>>>>> First, the K4D has a high 2 and 20 kHz dynamic range value of 101
>> dB.
>>>>>>> Because it's a direct-sampling radio, this figure will hold at
>> nearly
>>> all
>>>>>>> offsets from strong signals. Second is the block dynamic range
>> number
>>>>>> (128
>>>>>>> dB), higher than almost every other "pure" SDR measured. Finally,
>>> there's
>>>>>>> the LO noise (local oscillator; 148 to 155 dB) -- again, very
>>> favorable
>>>>>>> compared to all competing SDRs. This is an important number
>> correlated
>>>>>> with
>>>>>>> reciprocal mixing dynamic range (RMDR).
>>>>>>>
>>>>>>> Taken together these demonstrate that the K4D will offer excellent
>>>>>>> performance in crowded band conditions.
>>>>>>>
>>>>>>> Inevitably a question will arise regarding the chart position of the
>>> K4D
>>>>>>> relative to a couple of our other transceivers: the K3S and KX3.
>>> There's
>>>>>> a
>>>>>>> bit of "apples to oranges" in both comparisons.
>>>>>>>
>>>>>>> The K3S uses a superhet receiver architecture. The K4HD will
>> provide a
>>>>>>> receive setting that emulates this superhet performance when and if
>>> it's
>>>>>>> needed. But the "pure" (direct sampling) method used by the K4 (all
>>>>>> models)
>>>>>>> has many advantages. One is the elimination of artifacts associated
>>> with
>>>>>>> crystal filters. Another is that, as a pure SDR, the K4 has a far
>> more
>>>>>>> flexible architecture. We'll be able to provide updates to the
>> receive
>>>>>> and
>>>>>>> transmit digital signal chains that cannot be added to a superhet
>> like
>>>>>> the
>>>>>>> K3S or its competitors.
>>>>>>>
>>>>>>> The KX3 is another Elecraft radio high on Sherwood's chart. Its
>>>>>>> performance is excellent, especially at its price point. But its
>>> numbers
>>>>>>> relative to the K4 are somewhat misleading, as hinted at by Rob's
>>>>>>> footnotes. The KX3 uses a quadrature downsampling architecture,
>> which
>>>>>>> digitally samples at baseband audio rather than at RF. This is ideal
>>> for
>>>>>> a
>>>>>>> radio like the KX3 that has to have very low current drain for
>>> portable
>>>>>>> operations. The K4 uses a direct-samping architecture that requires
>> a
>>>>>>> higher power digital signal chain, resulting in important benefits
>>> over
>>>>>>> quadrature downsampling including much higher and more consistent
>>>>>> opposite
>>>>>>> sideband image suppression and 2nd-order intermod rejection. So the
>>> two
>>>>>> are
>>>>>>> really designed for different applications.
>>>>>>>
>>>>>>> Overall, this first independent test of the K4 validates the
>>> performance
>>>>>>> of our SDR architecture. Feel free to send us any further
>> performance
>>>>>>> questions.
>>>>>>>
>>>>>>> 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]
>>>>>>>
>>>>>> ______________________________________________________________
>>>>>> 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]
>>>
>>> ______________________________________________________________
>>> 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]
>
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