[Elecraft] Elecraft CW Net Report

[kevinr]

Good Evening,

   Signals were stronger than last week with less noise on both bands.  
QSB was a little higher on forty meters.  Most of you reported very nice 
weather.  Even out west the weather is not too bad once you allow for 
all the smoke.  It certainly makes working outside difficult.  Staying 
inside helps but I still have a stuffy nose and a mild headache.  My 
begonias don't like the smoke either, they are rapidly losing blossoms.


   The forty meter net improves as the days grow shorter.  I was able 
to reach Texas again.  Hopefully there will be some new sunspots this 
week.  That would help my reach.



  On 14050.8 kHz at 2200z:

W0CZ - Ken - ND

NO8V - John - MI

AB9V - Mike - IN

K6XK - Roy - IA


  On 7047.5 kHz at 0045z:

W0CZ - Ken - ND

K0DTJ - Brian - CA

K6PJV - Dale - CA

W8OV - Dave - TX


I plan to work inside again this week.  I need to collect wood but 
exercise in these smoky conditions makes the headaches worse. A week of 
rain starting tomorrow night will help.  Maybe they will slow the fires 
in the Cascades and clear our skies.  2020 has been quite a year.  I'm 
waiting for January so we can start over.


   Until next week 73,

  Kevin.  KD5ONS


-



cutting angle = degrees(atan2(twist, PI() * caliber))

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Re: [Elecraft] Why predistortion ?

[David Gilbert]

Of course, but that's a conscious choice by Elecraft and it does not 
result in the "cleanest, purest signals around."  I give Elecraft tons 
of credit for the other measures they have take to produce good signals, 
which is why I own and will keep my upgraded K3 probably forever, but 
K8JHR simply was incorrect in his comment and it makes a difference when 
considering the expanding focus by folks like Sherwood and others to 
clean up the bands.  When it comes to IMD, Elecraft is not one of the 
better players.  The fact that that's by choice doesn't change 
anything.  I suspect that 95+% of K3 rigs are used in portable/emergency 
situations less than 5% of the time.


73,
Dave   AB7E



On 9/13/2020 7:14 PM, Wayne Burdick wrote:

12 volts is a severe constraint for MOSFET PAs. But, like a lot of other 
manufacturers, we accept this constraint so the equipment can be used in a wide 
variety of portable/emergency power situations. As a result we have IMD numbers 
in exactly the same range as other products that are subject to this constraint.

On the other hand, our transceivers are best in class in terms of transmitted 
keying bandwidth. See paper by K9YC for example. Perhaps that's what JR was 
thinking of.

73,
Wayne
N6KR




On Sep 13, 2020, at 6:50 PM, David Gilbert  wrote:


I don't know where you got the idea that the K-Line produces the cleanest 
signals.  As several people have pointed out, because of the 12 volt finals the 
transmit IMD performance of the existing K-line is relatively poor.

Dave   AB7E


On 9/13/2020 2:32 PM, JR wrote:

Why are so many ops obsessed with predistortion?

The Elecraft K-Line already produces some of the cleanest, purest transmit 
signals around.   Do we need predistortion ?  If so, why, and how much better 
is it than what we already have?  Should I wait to buy a new rig until that is 
available?

Thanks and Happy Trails to all.   K8JHR

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Re: [Elecraft] Why predistortion ?

[Jim Brown]

On 9/13/2020 3:03 PM, Wayne Burdick wrote:

Virtually all class-AB-biased amplifier stages have worst-case 3rd-order IMD in 
the range of -30 dBc (ARRL method) on some HF bands. This reflects a limitation 
in the state of the art.


I hope that this feature will be implemented for CW as well. CW is 100% 
AM of a carrier by rectangular pulses, so any distortion in the transmit 
chain results in clicks. Elecraft pioneered very clean keying waveforms; 
it would be unfortunate for that to be lost with IMD in the power stages.


73, Jim K9YC
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Re: [Elecraft] Why predistortion ?

[Jim Brown]

On 9/13/2020 2:32 PM, JR wrote:
The Elecraft K-Line already produces some of the cleanest, purest 
transmit signals around.   Do we need predistortion ?


If you care about a clean signal, YES! If you don't mind being a bad 
neighbor, no.


73, Jim K9YC
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Re: [Elecraft] Why predistortion ?

[Wayne Burdick]

12 volts is a severe constraint for MOSFET PAs. But, like a lot of other 
manufacturers, we accept this constraint so the equipment can be used in a wide 
variety of portable/emergency power situations. As a result we have IMD numbers 
in exactly the same range as other products that are subject to this constraint.

On the other hand, our transceivers are best in class in terms of transmitted 
keying bandwidth. See paper by K9YC for example. Perhaps that's what JR was 
thinking of.

73,
Wayne
N6KR



> On Sep 13, 2020, at 6:50 PM, David Gilbert  wrote:
> 
> 
> I don't know where you got the idea that the K-Line produces the cleanest 
> signals.  As several people have pointed out, because of the 12 volt finals 
> the transmit IMD performance of the existing K-line is relatively poor.
> 
> Dave   AB7E
> 
> 
> On 9/13/2020 2:32 PM, JR wrote:
>> Why are so many ops obsessed with predistortion?
>> 
>> The Elecraft K-Line already produces some of the cleanest, purest transmit 
>> signals around.   Do we need predistortion ?  If so, why, and how much 
>> better is it than what we already have?  Should I wait to buy a new rig 
>> until that is available?
>> 
>> Thanks and Happy Trails to all.   K8JHR
> 
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Re: [Elecraft] Why predistortion ?

[Bill Frantz]

Wayne is right, it's the right thing to do. And we amateurs try 
to produce the best signals we can. (Ignore the wide CW signals 
during contests. :-) )


But the value will also show up during multi-op situations like 
running 14A during field day. Field day is much more fun if 
everyone gets a chance to operate.


73  Bill AE6JV


On 9/13/20 at 6:03 PM, n...@elecraft.com (Wayne Burdick) wrote:

Predistortion, correctly applied, can reduce interference 
between adjacent stations on a crowded band. This is a factor 
at least some fraction of the time during typical amateur radio 
use. Beyond that, the motivation for a “pure“ signal 
exemplifies the amateur spirit of cooperation, and is an 
example of keeping the hobby on the forefront of electrical design.


---
Bill Frantz| Privacy is dead, get over | Periwinkle
(408)348-7900  | it.   | 150 Rivermead 
Rd #235
www.pwpconsult.com |- Scott McNealy (1999) | Peterborough, 
NH 03458


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Re: [Elecraft] Why predistortion ?

[David Gilbert]

I don't know where you got the idea that the K-Line produces the 
cleanest signals.  As several people have pointed out, because of the 12 
volt finals the transmit IMD performance of the existing K-line is 
relatively poor.


Dave   AB7E


On 9/13/2020 2:32 PM, JR wrote:

Why are so many ops obsessed with predistortion?

The Elecraft K-Line already produces some of the cleanest, purest 
transmit signals around.   Do we need predistortion ?  If so, why, and 
how much better is it than what we already have?  Should I wait to buy 
a new rig until that is available?


Thanks and Happy Trails to all.   K8JHR


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Re: [Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Dave Cole]

Thanks Ken...  That is the next step...  Now I need to locate one...

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 9/13/20 4:24 PM, Ken Winterling wrote:
When you have issues like this the best test is to use a known good 
dummy load. That removes the antenna system from the equation. See what 
happens on 18mHz when transmitting into the summy load.


Ken
WA2LBI




On Sun, Sep 13, 2020 at 6:58 PM Dick Dievendorff > wrote:


When unpowered the KAT500 is bypassed, ANT1.

When the ATU is in mode BYP, yes, it’s bypassed.

73 de Dick, K6KR

 > On Sep 13, 2020, at 15:52, Dave Cole mailto:d...@nk7z.net>> wrote:
 >
 > Hello,
 > My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz.,
only. Antenna is a single feedline to a 6BTV, and an analyzer says
all is good at low power.  At 100 watts, all seems good.
 >
 > All other bands seem OK at high power.
 >
 > Question:  When in bypass, is the entire tuner bypassed?
 > Question:  When turned off is the tuner bypassed?  Which antenna
is default?
 > --
 > 73, and thanks,
 > Dave (NK7Z)
 > https://www.nk7z.net
 > ARRL Volunteer Examiner
 > ARRL Technical Specialist
 > ARRL Asst. Director, NW Division, Technical Resources
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Re: [Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Dave Cole]

That helps triage the issue...  Something in my antenna must have gone 
wonky...  I am using a 6BTV, with the 18 Meter add on kit, so the same 
feedpoint is used for all bands, and they are fine...  I was worried it 
was the tuner.  I'll go check the antenna out tonight, and in the 
morning as well...  THANK YOU!  Knowing the tuner is bypassed in Bypass, 
helps...  Next is to put a dummy load on the tuner...


73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 9/13/20 3:57 PM, Dick Dievendorff wrote:

When unpowered the KAT500 is bypassed, ANT1.

When the ATU is in mode BYP, yes, it’s bypassed.

73 de Dick, K6KR


On Sep 13, 2020, at 15:52, Dave Cole  wrote:

Hello,
My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz., only. Antenna is 
a single feedline to a 6BTV, and an analyzer says all is good at low power.  At 
100 watts, all seems good.

All other bands seem OK at high power.

Question:  When in bypass, is the entire tuner bypassed?
Question:  When turned off is the tuner bypassed?  Which antenna is default?
--
73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources
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Re: [Elecraft] Why predistortion ?

[W2xj]

wayne,

After you have the K4 fully put to bed, for your next project you might want to 
consider an amp that is directly driven by an I/Q stream.  The amplifier will 
be much more efficient (less power consumption) and you start out with less IMD 
before any pre-distortion.  

Sent from my iPad

> On Sep 13, 2020, at 6:05 PM, Wayne Burdick  wrote:
> 
> Hi JR,
> 
> Virtually all class-AB-biased amplifier stages have worst-case 3rd-order IMD 
> in the range of -30 dBc (ARRL method) on some HF bands. This reflects a 
> limitation in the state of the art. Even with adequate feedback and bias, an 
> amplifier operated in the vicinity of its 1 dB compression point (where it is 
> most efficient) will exhibit such characteristics.
> 
> To improve on this you either need to operate class A, which is highly 
> inefficient, or use predistortion. 
> 
> A small number of commercial transceivers are now providing predistortion, in 
> some cases as an optional/experimental setting (that not everyone uses, or at 
> least not all the time). There are constraints on predistortion power range 
> imposed by the headroom limit of the amplifier stage itself. Go over that 
> point and distortion will be worse than without predistortion. 
> 
> Predistortion, correctly applied, can reduce interference between adjacent 
> stations on a crowded band. This is a factor at least some fraction of the 
> time during typical amateur radio use. Beyond that, the motivation for a 
> “pure“ signal exemplifies the amateur spirit of cooperation, and is an 
> example of keeping the hobby on the forefront of electrical design.
> 
> Wayne,
> N6KR
> 
> 
> elecraft.com
> 
>> On Sep 13, 2020, at 2:34 PM, JR  wrote:
>> 
>> Why are so many ops obsessed with predistortion?
>> 
>> The Elecraft K-Line already produces some of the cleanest, purest transmit 
>> signals around.   Do we need predistortion ?  If so, why, and how much 
>> better is it than what we already have?  Should I wait to buy a new rig 
>> until that is available?
>> 
>> Thanks and Happy Trails to all.   K8JHR
>> _
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Re: [Elecraft] Why predistortion ?

[Wes]

You're kidding, right?

Wes  N7WS


On 9/13/2020 2:32 PM, JR wrote:
The Elecraft K-Line already produces some of the cleanest, purest transmit 
signals around


Thanks and Happy Trails to all.   K8JHR 


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[Elecraft] Why predistortion ?

[John Harper]

Here's a demonstration of predistortion in use (relevant part starts at the
10-minute point):
https://www.youtube.com/watch?v=0adHZOTqTlQ

John AE5X
https://ae5x.blogspot.com


>Why are so many ops obsessed with predistortion?
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Re: [Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Ken Winterling]

When you have issues like this the best test is to use a known good dummy
load. That removes the antenna system from the equation. See what happens
on 18mHz when transmitting into the summy load.

Ken
WA2LBI





On Sun, Sep 13, 2020 at 6:58 PM Dick Dievendorff  wrote:

> When unpowered the KAT500 is bypassed, ANT1.
>
> When the ATU is in mode BYP, yes, it’s bypassed.
>
> 73 de Dick, K6KR
>
> > On Sep 13, 2020, at 15:52, Dave Cole  wrote:
> >
> > Hello,
> > My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz., only.
> Antenna is a single feedline to a 6BTV, and an analyzer says all is good at
> low power.  At 100 watts, all seems good.
> >
> > All other bands seem OK at high power.
> >
> > Question:  When in bypass, is the entire tuner bypassed?
> > Question:  When turned off is the tuner bypassed?  Which antenna is
> default?
> > --
> > 73, and thanks,
> > Dave (NK7Z)
> > https://www.nk7z.net
> > ARRL Volunteer Examiner
> > ARRL Technical Specialist
> > ARRL Asst. Director, NW Division, Technical Resources
> > __
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Re: [Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Dick Dievendorff]

When unpowered the KAT500 is bypassed, ANT1.

When the ATU is in mode BYP, yes, it’s bypassed. 

73 de Dick, K6KR

> On Sep 13, 2020, at 15:52, Dave Cole  wrote:
> 
> Hello,
> My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz., only. Antenna 
> is a single feedline to a 6BTV, and an analyzer says all is good at low 
> power.  At 100 watts, all seems good.
> 
> All other bands seem OK at high power.
> 
> Question:  When in bypass, is the entire tuner bypassed?
> Question:  When turned off is the tuner bypassed?  Which antenna is default?
> -- 
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
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[Elecraft] KAT500: Fails to tune, and shows 3:1 on good antenna on 18 MHz.

[Dave Cole]

Hello,
My KAT500 which worked yesterday, now shows a 3:1 on 18 MHz., only. 
Antenna is a single feedline to a 6BTV, and an analyzer says all is good 
at low power.  At 100 watts, all seems good.


All other bands seem OK at high power.

Question:  When in bypass, is the entire tuner bypassed?
Question:  When turned off is the tuner bypassed?  Which antenna is default?
--
73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources
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Re: [Elecraft] Why predistortion ?

[Randy Farmer]

I can testify to the effectiveness of predistortion techniques from my 5 
years or so as a CDMA Cellular Base Station engineer with Motorola. The 
first generation of CDMA transmitters had a very specific "spectral 
mask" that had to be certified. As I recall, the transmitter output that 
met the Spectral Mask requirements of something like -60 dBc outside of 
the channel bandwidth showed up with essentially vertical sides (and a 
very flat top) on a spectrum analyzer. Obtaining this performance was 
neither cheap nor easy, and the associated testing was pretty stringent 
as well. Meeting the specs demanded very sophisticated predistortion 
techniques. Be glad that conventional SSB and the fairly simple 
waveforms used in amateur digital comms don't require too much dynamic 
headroom. The first generation CDMA waveform had a roughly 10:1, or 20dB 
peak-to-average power ratio. This meant that the transmitters we 
designed to produce 20W average power were actually capable of 200W 
continuous output power and still met the spectral mask IMD 
requirements. Putting multiple carriers through the PA required either 
higher power capability or derating the power output for each individual 
carrier. I no longer work in the industry, so I don't know what the 
current generation of signals requires, but with the greater bandwidths 
and more complex modulation schemes used now you can bet the 
requirements, and therefore the transmitter design challenge, didn't get 
any easier.


73...
Randy, W8FN

On 9/13/2020 6:03 PM, Wayne Burdick wrote:

Hi JR,

Virtually all class-AB-biased amplifier stages have worst-case 3rd-order IMD in 
the range of -30 dBc (ARRL method) on some HF bands. This reflects a limitation 
in the state of the art. Even with adequate feedback and bias, an amplifier 
operated in the vicinity of its 1 dB compression point (where it is most 
efficient) will exhibit such characteristics.

To improve on this you either need to operate class A, which is highly 
inefficient, or use predistortion.

A small number of commercial transceivers are now providing predistortion, in 
some cases as an optional/experimental setting (that not everyone uses, or at 
least not all the time). There are constraints on predistortion power range 
imposed by the headroom limit of the amplifier stage itself. Go over that point 
and distortion will be worse than without predistortion.

Predistortion, correctly applied, can reduce interference between adjacent 
stations on a crowded band. This is a factor at least some fraction of the time 
during typical amateur radio use. Beyond that, the motivation for a “pure“ 
signal exemplifies the amateur spirit of cooperation, and is an example of 
keeping the hobby on the forefront of electrical design.

Wayne,
N6KR


elecraft.com

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Re: [Elecraft] Why predistortion ?

[E.H. Russell]

Well put.

TKS,
73 ED W2RF




-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Wayne Burdick
Sent: Sunday, September 13, 2020 6:03 PM
To: JR 
Cc: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Why predistortion ?

Hi JR,

Virtually all class-AB-biased amplifier stages have worst-case 3rd-order IMD in 
the range of -30 dBc (ARRL method) on some HF bands. This reflects a limitation 
in the state of the art. Even with adequate feedback and bias, an amplifier 
operated in the vicinity of its 1 dB compression point (where it is most 
efficient) will exhibit such characteristics.

To improve on this you either need to operate class A, which is highly 
inefficient, or use predistortion. 

A small number of commercial transceivers are now providing predistortion, in 
some cases as an optional/experimental setting (that not everyone uses, or at 
least not all the time). There are constraints on predistortion power range 
imposed by the headroom limit of the amplifier stage itself. Go over that point 
and distortion will be worse than without predistortion. 

Predistortion, correctly applied, can reduce interference between adjacent 
stations on a crowded band. This is a factor at least some fraction of the time 
during typical amateur radio use. Beyond that, the motivation for a “pure“ 
signal exemplifies the amateur spirit of cooperation, and is an example of 
keeping the hobby on the forefront of electrical design.

Wayne,
N6KR


elecraft.com

> On Sep 13, 2020, at 2:34 PM, JR  wrote:
> 
> Why are so many ops obsessed with predistortion?
> 
> The Elecraft K-Line already produces some of the cleanest, purest transmit 
> signals around.   Do we need predistortion ?  If so, why, and how much better 
> is it than what we already have?  Should I wait to buy a new rig until that 
> is available?
> 
> Thanks and Happy Trails to all.   K8JHR
> _
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Re: [Elecraft] Why predistortion ?

[Wayne Burdick]

Hi JR,

Virtually all class-AB-biased amplifier stages have worst-case 3rd-order IMD in 
the range of -30 dBc (ARRL method) on some HF bands. This reflects a limitation 
in the state of the art. Even with adequate feedback and bias, an amplifier 
operated in the vicinity of its 1 dB compression point (where it is most 
efficient) will exhibit such characteristics.

To improve on this you either need to operate class A, which is highly 
inefficient, or use predistortion. 

A small number of commercial transceivers are now providing predistortion, in 
some cases as an optional/experimental setting (that not everyone uses, or at 
least not all the time). There are constraints on predistortion power range 
imposed by the headroom limit of the amplifier stage itself. Go over that point 
and distortion will be worse than without predistortion. 

Predistortion, correctly applied, can reduce interference between adjacent 
stations on a crowded band. This is a factor at least some fraction of the time 
during typical amateur radio use. Beyond that, the motivation for a “pure“ 
signal exemplifies the amateur spirit of cooperation, and is an example of 
keeping the hobby on the forefront of electrical design.

Wayne,
N6KR


elecraft.com

> On Sep 13, 2020, at 2:34 PM, JR  wrote:
> 
> Why are so many ops obsessed with predistortion?
> 
> The Elecraft K-Line already produces some of the cleanest, purest transmit 
> signals around.   Do we need predistortion ?  If so, why, and how much better 
> is it than what we already have?  Should I wait to buy a new rig until that 
> is available?
> 
> Thanks and Happy Trails to all.   K8JHR
> _
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[Elecraft] Why predistortion ?

[JR]

Why are so many ops obsessed with predistortion?

The Elecraft K-Line already produces some of the cleanest, purest 
transmit signals around.   Do we need predistortion ?  If so, why, and 
how much better is it than what we already have?  Should I wait to buy a 
new rig until that is available?


Thanks and Happy Trails to all.   K8JHR
_
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Re: [Elecraft] K4 Predistortion planned? timetable?

[turnbull]

Wayne and friends, This recent correspondence is one of the reasons why I value 
Elecraft.   The design engineers come down to their users and give insight.   
It was the right decision to plonk down that deposit.The smoke will clear and 
Elecraft will be in the California sun; there is reason for naming it the 
golden state.   I pray you are left with plenty of forest for your hikes.73 
Doug EI2CNSent from my Samsung Galaxy smartphone.
 Original message From: Wayne Burdick  Date: 
13/09/2020  18:42  (GMT+00:00) To: Robert Sands  Cc: 
Elecraft Reflector  Subject: Re: [Elecraft] K4 
Predistortion planned? timetable? > Robert Sands  wrote:> 
> Is the processor in the K4 fast or big enough to handle the demand of the 
anticipated predistortion algorithm?Yes. Modulation and demodulation is handled 
by a dedicated, very fast floating-point DSP with various on-chip accelerators. 
The panadapters run from separate hardware, so the DSP has plenty of cycles to 
burn, especially in transmit mode.> Is this predistortion algorithm a 
proprietary matter or is it constructed de novo from existing knowledge?There 
are three parts to this. First you need the appropriate hardware paths, which 
we already have in place: RF sampling of the reference waveform as well as the 
internal or external transmit signal. Second, the DSP has to apply complex 
curve fitting at baseband. This is typically done with several terms of a 
Volterra series, etc.Finally you need an algorithm for adaptive convergence on 
the ideal coefficients. This can range from LMS (least-mean-squares) to 
back-propagation (neural net). This is the "fun" (time consuming) part of the 
R, with tradeoffs in performance vs. processing time vs. staff availability. 
Given the multitude of distractions I can't say exactly how long this will 
take. It's likely that a simpler version of the algorithm will be available 
initially, allowing for early 
evaluation.73,WayneN6KR__Elecraft
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Re: [Elecraft] K4 Predistortion planned? timetable?

[Wayne Burdick]

> Robert Sands  wrote:
> 
> Is the processor in the K4 fast or big enough to handle the demand of the 
> anticipated predistortion algorithm?

Yes. Modulation and demodulation is handled by a dedicated, very fast 
floating-point DSP with various on-chip accelerators. The panadapters run from 
separate hardware, so the DSP has plenty of cycles to burn, especially in 
transmit mode.


> Is this predistortion algorithm a proprietary matter or is it constructed de 
> novo from existing knowledge?

There are three parts to this. 

First you need the appropriate hardware paths, which we already have in place: 
RF sampling of the reference waveform as well as the internal or external 
transmit signal. 

Second, the DSP has to apply complex curve fitting at baseband. This is 
typically done with several terms of a Volterra series, etc.

Finally you need an algorithm for adaptive convergence on the ideal 
coefficients. This can range from LMS (least-mean-squares) to back-propagation 
(neural net). This is the "fun" (time consuming) part of the R, with 
tradeoffs in performance vs. processing time vs. staff availability. Given the 
multitude of distractions I can't say exactly how long this will take. It's 
likely that a simpler version of the algorithm will be available initially, 
allowing for early evaluation.

73,
Wayne
N6KR
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[Elecraft] There is a new release of Win4K3Suite

[Tom]

Hello,
There is a new version of Win4K3Suite available.  This release has a number
of updates improving reliability.

Win4K3Suite is a full featured control program for the K3/S, KX3 and KX2.
It has a built in Panadapter that works with LPPAN and a sound card, as well
as the SDRPlay RSP's. It supports the KAT500, KPA500/1500 and the KXPA100 on
most of the above radios.  
A unique feature is that is has 6 built in Virtual Radios, each of which
works just like an Elecraft radio.  This allows sharing of a single COM port
with up to 6 applications.  It also has a built in HRDLogbook server and the
EiBi Shortwave database.
There are many more features like full access to menu items, a cluster
display using your ClubLog credentials and many more.
You see more information here:
https://www.youtube.com/results?search_query=win4k3suite
and download a fully functional 30 day trial at va2fsq.com

73 Tom
va2fsq.com


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Re: [Elecraft] K9YC

[Mike VE3YF]

Jim::

Congratulations on conditions of the house. Your fingers must have been 
crossed. Continue to stay safe and be well.


Don't want to forget, thanks for all you have done to help others and 
myself thru your various articles, also congratulations on your 2020 
ARRL Technical Service Award. Well Deserved...


--

*73 De Mike*
*VE3YF

_/http://www.ve3yf.com/_*

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Re: [Elecraft] K9YC

[Dave Cole]

Congratz Jim!  On both, a house that is intact, and your receiving the 
ARRL Tech Services Award!


73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist
ARRL Asst. Director, NW Division, Technical Resources

On 9/13/20 6:40 AM, Bill Steffey NY9H wrote:

Glad your home made it thru the fires hope you get home soon !!!

Very Great to hear you were awarded the ARRL Tech Services Award.. 
you certainly earned it.


http://www.arrl.org/news/arrl-technical-service-award-conferred

It's fun to see you and a few other brains here keep some of the "myths" 
quiet.  Especially the audio related .


As Jim moved to California from Chicago he scooped up my TenTec Titan to 
start his "Titan" collection. Jim & I go back to the audio business in 
Chicago 1980s/90s...   glad I can say this smart cookie is a friend.


bill ny9h/3


Have you been able to get home yet? What's the status of your home and 
antennas?


Got back a few days ago, only damage is to floor under refrigerator 
that had been without power for 3 wks. House, shack, antennas all 
fine. No power, water, or internet, so we're in a rental townhouse for 
a while.


73, Jim K9YC




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[Elecraft] K9YC

[Bill Steffey NY9H]

Glad your home made it thru the fires hope you get home soon !!!

Very Great to hear you were awarded the ARRL Tech Services Award..   
you certainly earned it.


http://www.arrl.org/news/arrl-technical-service-award-conferred

It's fun to see you and a few other brains here keep some of the "myths" 
quiet.  Especially the audio related .


As Jim moved to California from Chicago he scooped up my TenTec Titan to 
start his "Titan" collection. Jim & I go back to the audio business in 
Chicago 1980s/90s...   glad I can say this smart cookie is a friend.


bill ny9h/3


Have you been able to get home yet? What's the status of your home and 
antennas?


Got back a few days ago, only damage is to floor under refrigerator 
that had been without power for 3 wks. House, shack, antennas all 
fine. No power, water, or internet, so we're in a rental townhouse for 
a while.


73, Jim K9YC



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Re: [Elecraft] K1ZTE - KAT500

[Andy Durbin]

"Tuning solutions are saved for each "bin" and there are many "bins" in each 
band.  Each bin stores up to 6 tuning solutions and each solution includes the 
antenna selection."

Here is an example of a bin that contains tuning solutions for AN1 and AN3:

dm14076;
DM BN05;BIN 53;FR 14061-14080;ADDR 34804;
AN1;BYPN;SIDEA;C07;L07;VSWRB 1.49;
AN3;BYPN;SIDEA;C00;L04;VSWRB 1.00;
AN1;BYPN;SIDEA;C06;L09;VSWRB 1.43;
AN1;BYPN;SIDEA;C02;L06;VSWRB 1.56;
AN1;BYPN;SIDEA;C00;L07;VSWRB 1.43;
AN1;BYPN;SIDET;C00;L07;VSWRB 1.43;

On 20 m band Antenna 3 is my dummy load.

If the bin contains 6 saved solutions then each new solution pushes the stack 
and the bottom (oldest) solution is lost.

Andy, k3wyc

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[Elecraft] K1ZTE - KAT500

[Andy Durbin]

"Is the training saved per-BAND/ANTENNA combination tuning solution?.. possibly 
resulting in 3 solutions per band."

Tuning solutions are saved for each "bin" and there are many "bins" in each 
band.  Each bin stores up to 6 tuning solutions and each solution includes the 
antenna selection.

You can inspect the tuning solutions for each bin with command DMf;  where f is 
frequency in kHz.

e.g.
DM14200;

returns:
DM BN05;BIN 59;FR 14181-14200;ADDR 35020;
AN1;BYPN;SIDET;C00;L05;VSWRB 1.42;
AN1;BYPN;SIDEA;C00;L04;VSWRB 1.42;
AN1;BYPB;VSWRB 1.00;
AN1;BYPN;SIDET;C03;L07;VSWRB 1.00;
AN1;BYPN;SIDEA;C00;L06;VSWRB 1.00;
UNUSED

Andy, k3wyc
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