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K4 Receive Filter question

I believe there are no crystal Roofing Filters in the standard K4 model. Yet the manual talks about "one set of receive filters". Please advise the type and bandwidth of these filters? (DSP?)

From the K4 Manual: There are three models: the basic K4, with one set of receive filters and one analog-to-digital converter (ADC); the K4D, with a second set of receive filters and a second ADC; and the K4HD, which adds a superheterodyne front end that can be enabled as needed to provide even greater dynamic range. The superhet module uses high-performance, narrow-band crystal filters such as those used in the Elecraft K3S. Thanks & 73, Dick- K9OM
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Grant Youngman-2

Re: K4 Receive Filter question

This refers to the RF bandpass filters in the receiver front end.

Geant NQ5T

> On Jan 19, 2021, at 12:43 AM, RVZ via Elecraft <[hidden email]> wrote:
>
> I believe there are no crystal Roofing Filters in the standard K4 model. Yet the manual talks about "one set of receive filters". Please advise the type and bandwidth of these filters? (DSP?)
>
> From the K4 Manual: There are three models: the basic K4, with one set of receive filters and one analog-to-digital converter (ADC); the K4D, with a second set of receive filters and a second ADC; and the K4HD, which adds a superheterodyne front end that can be enabled as needed to provide even greater dynamic range. The superhet module uses high-performance, narrow-band crystal filters such as those used in the Elecraft K3S. Thanks & 73, Dick- K9OM
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
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BRUCE WW8II

Re: K4 Receive Filter question

In reply to this post by Elecraft mailing list

I also would appreciate a real answer to the question. The question is
will the K4 or K4D be as good or better on receive than my K3s with the
2.1kHz and the 200Hz filters.

Bruce WW8II

On Tue, Jan 19, 2021 at 12:56 AM RVZ via Elecraft <[hidden email]>
wrote:

> I believe there are no crystal Roofing Filters in the standard K4 model.
> Yet the manual talks about "one set of receive filters". Please advise the
> type and bandwidth of these filters? (DSP?)
>
> From the K4 Manual: There are three models: the basic K4, with one set of
> receive filters and one analog-to-digital converter (ADC); the K4D, with a
> second set of receive filters and a second ADC; and the K4HD, which adds a
> superheterodyne front end that can be enabled as needed to provide even
> greater dynamic range. The superhet module uses high-performance,
> narrow-band crystal filters such as those used in the Elecraft K3S. Thanks
> & 73, Dick- K9OM
> ______________________________________________________________
> 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: K4 Receive Filter question

That's not a simple or easy question to answer, especially since there's been no independent test of a K4, and there are many different criteria that go into it. That said, I'll go out on a limb and say that in most all practical situations on the air, it won't be. I say that because I've listened to and half-assedly compared a number of very good radios and some less good radios on the air. They might sound different, and take some tweaking of the controls to make them sound a similar as possible, but in the end I couldn't copy sigs better on one than the other. The K3 is really good in the tests, and I'm confident the K4 will surpass it, but that's at level that will only matter in what I consider to be exceptional circumstances.

I'll add that I'm not the radio connoisseur that some are, and what I feel is largely the same, others may find hugely different. That doesn't stop me from wanting the best, even if I believe it won't make a practical difference in my operating.

On Tuesday, January 19, 2021, 12:47:17 AM MST, BRUCE WW8II <[hidden email]> wrote:

I also would appreciate a real answer to the question. The question is
will the K4 or K4D be as good or better on receive than my K3s with the
2.1kHz and the 200Hz filters.

Bruce WW8II

On Tue, Jan 19, 2021 at 12:56 AM RVZ via Elecraft <[hidden email]>
wrote:

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wayne burdick

Explained: K4/K4D receive performance vs. K3S

Administrator

In reply to this post by BRUCE WW8II

> BRUCE WW8II <[hidden email]> wrote:
>
> The question is will the K4 or K4D be as good or better on receive than my K3s with the
> 2.1kHz and the 200Hz filters.
>
> Bruce WW8II

Bruce,

First, a bit of background would help since they're two different architectures.

The K4/K4D are "pure" SDRs, meaning they're more agile in frequency, operating modes, modulation and demodulation, features in general, and extensibility. A lot of the flexibility of the design is in service of the built-in and external displays as well as remote control. The K4/K4D also have a lot more digital and RF I/O, satisfying the demand for a modern, integrated station. For example you can directly attach a keyboard, mouse, HDMI monitor, and flash storage drives or other USB devices.

By contrast, the K3S is a superhet, with emphasis primarily on receive close-in dynamic range performance rather than integration, agility, extensibility. The use of crystal filters is an advantage in raw performance, at the expense of passband flatness, available bandwidths, and group delay.

The K4HD will be a hybrid of the two: When the extra dynamic range is needed, you can turn on the HDR module, which is essentially two superhet downconverters, one for the main receiver and the other for the sub. But the HDR module is, in practice, rarely needed unless you have high-power transmitters in close proximity. Examples of this situation include multi-transmitter contest or DXpedition stations, those living in the shadow of a broadcast station, and those with very nearby ham neighbors.

With this context we can now talk about receiver performance.

- The K4/K4D are very similar to competing pure SDRs using 16 bit, wide-band A-to-D converters: signal handling is excellent by any measure, and there's plenty of headroom in all but the most heavily impacted RF environments.

- Compared to *any* pure SDR, the K3S (and a few other superhets) will have a few dB higher third-order intercept point. (Note that Sherwood's chart still shows the Flex 6700, a pure SDR, at 108 dB. He corrected this later to a much lower number -- see the '6700 footnotes in the far right column.)

- The K4HD will be in the same ballpark as the K3S, though we're still refining the design and our goal is for it to be higher. (The limitation with any superhet is the crystal filters, and we carefully control the quality of our suppliers.)

73,
Wayne
N6KR

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BRUCE WW8II

Re: K4 Receive Filter question

In reply to this post by Elecraft mailing list

I work in the 2 to 3 db above the noise floor CW, and 6 to 10 db above the
noise floor on SSB now, (that is why I presently own a K3s and a P3VGA) so
I guess I will have to wait for the real answer. I really cannot
believe that Elecraft did not run their own test. If and when I spend my
cash I am not looking for the pretty blinkie colored lights and a fancy
screen, I want performance. My really big issue is: receiver noise floor,
sensitivity and DSP that does not distort or degrade the incoming signal.
But thank all of you for your input and I truly appreciate all the
comments.

Bruce
WW8II

On Tue, Jan 19, 2021 at 10:43 AM Louandzip via Elecraft <
[hidden email]> wrote:

> That's not a simple or easy question to answer, especially since there's
> been no independent test of a K4, and there are many different criteria
> that go into it. That said, I'll go out on a limb and say that in most
> all practical situations on the air, it won't be. I say that because I've
> listened to and half-assedly compared a number of very good radios and some
> less good radios on the air. They might sound different, and take some
> tweaking of the controls to make them sound a similar as possible, but in
> the end I couldn't copy sigs better on one than the other. The K3 is really
> good in the tests, and I'm confident the K4 will surpass it, but that's at
> level that will only matter in what I consider to be exceptional
> circumstances.
>
> I'll add that I'm not the radio connoisseur that some are, and what I feel
> is largely the same, others may find hugely different. That doesn't stop me
> from wanting the best, even if I believe it won't make a practical
> difference in my operating.
>
>
>
>
> On Tuesday, January 19, 2021, 12:47:17 AM MST, BRUCE WW8II <
> [hidden email]> wrote:
>
> I also would appreciate a real answer to the question. The question is
> will the K4 or K4D be as good or better on receive than my K3s with the
> 2.1kHz and the 200Hz filters.
>
> Bruce WW8II
>
> On Tue, Jan 19, 2021 at 12:56 AM RVZ via Elecraft <
> [hidden email]>
> wrote:
>
> > I believe there are no crystal Roofing Filters in the standard K4 model.
> > Yet the manual talks about "one set of receive filters". Please advise
> the
> > type and bandwidth of these filters? (DSP?)
> >
> > From the K4 Manual: There are three models: the basic K4, with one set
> of
> > receive filters and one analog-to-digital converter (ADC); the K4D, with
> a
> > second set of receive filters and a second ADC; and the K4HD, which adds
> a
> > superheterodyne front end that can be enabled as needed to provide even
> > greater dynamic range. The superhet module uses high-performance,
> > narrow-band crystal filters such as those used in the Elecraft K3S.
> Thanks
> > & 73, Dick- K9OM
> > ______________________________________________________________
> > 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
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> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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David Box-2

Re: K4 Receive Filter question

Bruce,

Below are the receiver sensitivity specs from page 42 of the recently
updated manual

Sensitivity    (MDS)

(Typical    values;    main    or
sub    RX,    BW    =    500    Hz)

0.1-1.5    MHz*:                Preamp    OFF/1/2: -120/-130/-135
dBm
1.5-23    MHz:                            Preamp    OFF/1/2:
-120/-132/-137    dBm
23-54    MHz:                                Preamp    OFF/1/2:
-120/-132/-141    dBm
*0.1-1.5    MHz    MDS    measured    at    RX    antenna inputs.    When
using    shared    RX/TX    antenna,    sensitivity decreases
below    1.5
MHz    due    to    intentional    high-pass    response    of T-R
switch.

de Dave K5MWR

On 1/19/2021 12:40, BRUCE WW8II wrote:

> I work in the 2 to 3 db above the noise floor CW, and 6 to 10 db above the
> noise floor on SSB now, (that is why I presently own a K3s and a P3VGA) so
> I guess I will have to wait for the real answer. I really cannot
> believe that Elecraft did not run their own test. If and when I spend my
> cash I am not looking for the pretty blinkie colored lights and a fancy
> screen, I want performance. My really big issue is: receiver noise floor,
> sensitivity and DSP that does not distort or degrade the incoming signal.
> But thank all of you for your input and I truly appreciate all the
> comments.
>
> Bruce
> WW8II
>
>
>
> On Tue, Jan 19, 2021 at 10:43 AM Louandzip via Elecraft <
> [hidden email]> wrote:
>
>> That's not a simple or easy question to answer, especially since there's
>> been no independent test of a K4, and there are many different criteria
>> that go into it. That said, I'll go out on a limb and say that in most
>> all practical situations on the air, it won't be. I say that because I've
>> listened to and half-assedly compared a number of very good radios and some
>> less good radios on the air. They might sound different, and take some
>> tweaking of the controls to make them sound a similar as possible, but in
>> the end I couldn't copy sigs better on one than the other. The K3 is really
>> good in the tests, and I'm confident the K4 will surpass it, but that's at
>> level that will only matter in what I consider to be exceptional
>> circumstances.
>>
>> I'll add that I'm not the radio connoisseur that some are, and what I feel
>> is largely the same, others may find hugely different. That doesn't stop me
>> from wanting the best, even if I believe it won't make a practical
>> difference in my operating.
>>
>>
>>
>>
>> On Tuesday, January 19, 2021, 12:47:17 AM MST, BRUCE WW8II <
>> [hidden email]> wrote:
>>
>> I also would appreciate a real answer to the question. The question is
>> will the K4 or K4D be as good or better on receive than my K3s with the
>> 2.1kHz and the 200Hz filters.
>>
>> Bruce WW8II
>>
>> On Tue, Jan 19, 2021 at 12:56 AM RVZ via Elecraft <
>> [hidden email]>
>> wrote:
>>
>>> I believe there are no crystal Roofing Filters in the standard K4 model.
>>> Yet the manual talks about "one set of receive filters". Please advise
>> the
>>> type and bandwidth of these filters? (DSP?)
>>>
>>> From the K4 Manual: There are three models: the basic K4, with one set
>> of
>>> receive filters and one analog-to-digital converter (ADC); the K4D, with
>> a
>>> second set of receive filters and a second ADC; and the K4HD, which adds
>> a
>>> superheterodyne front end that can be enabled as needed to provide even
>>> greater dynamic range. The superhet module uses high-performance,
>>> narrow-band crystal filters such as those used in the Elecraft K3S.
>> Thanks
>>> & 73, Dick- K9OM
>>> ______________________________________________________________
>>> 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]
>

George Thornton

Re: K4 Receive Filter question

In reply to this post by BRUCE WW8II

I have followed the Sherwood Receiver test data over the years and I know Elecraft has always been in or near the top spot.

I also would be reluctant to upgrade to a K4 if my K3 is the same or pretty close to the same in the key performance characteristics.

I wonder whether we are nearing the theoretical limit of what can be gained in receiver performance.

The difference among the top eight to ten on the Sherwood list is not likely to be practically significant.

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of BRUCE WW8II
Sent: Tuesday, January 19, 2021 10:40 AM
To: Louandzip <[hidden email]>
Cc: elecraft <[hidden email]>
Subject: Re: [Elecraft] K4 Receive Filter question

I work in the 2 to 3 db above the noise floor CW, and 6 to 10 db above the noise floor on SSB now, (that is why I presently own a K3s and a P3VGA) so I guess I will have to wait for the real answer. I really cannot believe that Elecraft did not run their own test. If and when I spend my cash I am not looking for the pretty blinkie colored lights and a fancy screen, I want performance. My really big issue is: receiver noise floor, sensitivity and DSP that does not distort or degrade the incoming signal.
But thank all of you for your input and I truly appreciate all the comments.

Bruce
WW8II

On Tue, Jan 19, 2021 at 10:43 AM Louandzip via Elecraft < [hidden email]> wrote:

> That's not a simple or easy question to answer, especially since
> there's been no independent test of a K4, and there are many different
> criteria that go into it. That said, I'll go out on a limb and say
> that in most all practical situations on the air, it won't be. I say
> that because I've listened to and half-assedly compared a number of
> very good radios and some less good radios on the air. They might
> sound different, and take some tweaking of the controls to make them
> sound a similar as possible, but in the end I couldn't copy sigs
> better on one than the other. The K3 is really good in the tests, and
> I'm confident the K4 will surpass it, but that's at level that will
> only matter in what I consider to be exceptional circumstances.
>
> I'll add that I'm not the radio connoisseur that some are, and what I
> feel is largely the same, others may find hugely different. That
> doesn't stop me from wanting the best, even if I believe it won't make
> a practical difference in my operating.
>
>
>
>
> On Tuesday, January 19, 2021, 12:47:17 AM MST, BRUCE WW8II <
> [hidden email]> wrote:
>
> I also would appreciate a real answer to the question. The question
> is will the K4 or K4D be as good or better on receive than my K3s with
> the 2.1kHz and the 200Hz filters.
>
> Bruce WW8II
>
> On Tue, Jan 19, 2021 at 12:56 AM RVZ via Elecraft <
> [hidden email]>
> wrote:
>
> > I believe there are no crystal Roofing Filters in the standard K4 model.
> > Yet the manual talks about "one set of receive filters". Please
> > advise
> the
> > type and bandwidth of these filters? (DSP?)
> >
> > From the K4 Manual: There are three models: the basic K4, with one
> > set
> of
> > receive filters and one analog-to-digital converter (ADC); the K4D,
> > with
> a
> > second set of receive filters and a second ADC; and the K4HD, which
> > adds
> a
> > superheterodyne front end that can be enabled as needed to provide
> > even greater dynamic range. The superhet module uses
> > high-performance, narrow-band crystal filters such as those used in the Elecraft K3S.
> Thanks
> > & 73, Dick- K9OM
> > ______________________________________________________________
> > 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]

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Elecraft mailing list

Re: K4 Receive Filter question

I own a radio that's currently #1 on Sherwood's list. My 20 year old K2 is essentially equal at digging weak CW out of the noise (always dominated by band noise and not the noise floor of the rig) in virtually all situations I've run into. The K2 has no KSSB so I don't compare it on SSB. If I was up against a lot of really strong close-by sigs, presumably the new rig would win, but I haven't yet run into a situation with the two rigs side by side where big nearby sigs have actually caused a discernible difference.
Comparing SSB with other rigs, the new rig can beat the others on readability of weak sigs in noise, but I don't think it's due to the fundamental performance numbers in these cases but rather the DSP algorithm which makes the difference, and I don't believe this is quantified in the testing done by Sherwood or ARRL, except perhaps in subjective comments in the text of a QST review. .

On Tuesday, January 19, 2021, 12:13:20 PM MST, George Thornton <[hidden email]> wrote:

I have followed the Sherwood Receiver test data over the years and I know Elecraft has always been in or near the top spot.

I also would be reluctant to upgrade to a K4 if my K3 is the same or pretty close to the same in the key performance characteristics.

I wonder whether we are nearing the theoretical limit of what can be gained in receiver performance.

The difference among the top eight to ten on the Sherwood list is not likely to be practically significant.

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of BRUCE WW8II
Sent: Tuesday, January 19, 2021 10:40 AM
To: Louandzip <[hidden email]>
Cc: elecraft <[hidden email]>
Subject: Re: [Elecraft] K4 Receive Filter question

I work in the 2 to 3 db above the noise floor CW, and 6 to 10 db above the noise floor on SSB now, (that is why I presently own a K3s and a P3VGA) so I guess I will have to wait for the real answer. I really cannot believe that Elecraft did not run their own test. If and when I spend my cash I am not looking for the pretty blinkie colored lights and a fancy screen, I want performance. My really big issue is: receiver noise floor, sensitivity and DSP that does not distort or degrade the incoming signal.
But thank all of you for your input and I truly appreciate all the comments.

Bruce
WW8II

On Tue, Jan 19, 2021 at 10:43 AM Louandzip via Elecraft < [hidden email]> wrote:

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Wes Stewart-2

Re: K4 Receive Filter question

I happen to own the K3S that is #5 or Rob's list. I also got tired of waiting
on the K4 and having a burning desire for a new radio I have a month-old TS-890,
which is now my primary radio. The K3S is set up in a receive-only state,
sharing the RX antenna out of the '890.

A few mornings ago I was tuning 160 near sunrise and copied a fishing buoy 60 Hz
above one of the commonly used frequencies (forget which one). My friend, and
local ham, N7DD began calling CQ 60 Hz below the buoy. Larry runs an Icom 7851,
which is very clean and a BIG amplifier. He is at least S9+40 db. On the
TS-890, cranked down to 80 Hz BW, I could still copy the buoy which was S6 or
so. On the K3S I heard N7DD calling CQ.

Without QRM the rigs are comparable at hearing signals in the noise but the
Kenwood sounds better.

Wes N7WS

On 1/19/2021 12:38 PM, Louandzip via Elecraft wrote:

> I own a radio that's currently #1 on Sherwood's list. My 20 year old K2 is essentially equal at digging weak CW out of the noise (always dominated by band noise and not the noise floor of the rig) in virtually all situations I've run into. The K2 has no KSSB so I don't compare it on SSB. If I was up against a lot of really strong close-by sigs, presumably the new rig would win, but I haven't yet run into a situation with the two rigs side by side where big nearby sigs have actually caused a discernible difference.
> Comparing SSB with other rigs, the new rig can beat the others on readability of weak sigs in noise, but I don't think it's due to the fundamental performance numbers in these cases but rather the DSP algorithm which makes the difference, and I don't believe this is quantified in the testing done by Sherwood or ARRL, except perhaps in subjective comments in the text of a QST review. .
>
> On Tuesday, January 19, 2021, 12:13:20 PM MST, George Thornton <[hidden email]> wrote:
>
> I have followed the Sherwood Receiver test data over the years and I know Elecraft has always been in or near the top spot.
>
> I also would be reluctant to upgrade to a K4 if my K3 is the same or pretty close to the same in the key performance characteristics.
>
> I wonder whether we are nearing the theoretical limit of what can be gained in receiver performance.
>
> The difference among the top eight to ten on the Sherwood list is not likely to be practically significant.

Bill Frantz

Re: K4 Receive Filter question

In reply to this post by BRUCE WW8II

Not to pick on Bruce, but there have been many posts to this
thread with essentially the same thought.

However, none of them talk about what I see as one of the most
important performance characteristics, which is the user
interface (UI). How easy it the radio to use?

For me, I do a lot of digital modes. Here I want to monitor all
of the power output, SWR, and ALC. On my K3, I have to switch
between them. On the K4 I can have them all on the screen.

How easy is it to tune to a signal I see on the panadapter? On
the P3, I need to move the cursor (via a knob) to be on top of
the signal and press a button. Honestly, it's easier to turn the
big knob. On the K4 I touch the touch screen. (I hope this
screen is better at detecting my touch than my iPhone.)

There are probably a bunch of other examples too.

And, since I'm interested in remote operation, I think that will
be a lot easier with a K4.

And I haven't even mentioned TX or RX performance. But it's an
Elecraft, so I'm not worried.

73 Bill AE6JV

On 1/19/21 at 1:40 PM, [hidden email] (BRUCE WW8II) wrote:

>If and when I spend my
>cash I am not looking for the pretty blinkie colored lights and a fancy
>screen, I want performance.

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Jim Brown-10

Re: K4 Receive Filter question

On 1/19/2021 5:24 PM, Bill Frantz wrote:
> one of the most important performance characteristics, which is the user
> interface (UI). How easy it the radio to use?

YUP! And like Bill, I find the Elecraft UI excellent, VERY intuitive for
users of RADIOS, with anything you need while USING them to be on knobs
or switches on the front panel, with once-in-a-while tweaks like VOX and
ANTI-VOX, or choosing between mic or mic plus computer playback for a
contest, do I want my mic on the front or rear panel, and what
accessories or options are in my radio are on a top level menu.

73, Jim K9YC

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