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VE3GNO Daniel

Re: New beta K3 firmware!

Hi All,

I dream one day to see Elecraft building some kind of expansion slot to accomodate more filters. Now all my slots are filled, 200/400/2.1k/2.8k/FM x2 for both RXs so no more free slots for AM or any other filter. I don't care too much abt AM filter but I would like to squeeze two more filters, maybe a 800 and 1.5k filter. Wayne, do you see technical possible to accomodate some sort of optional expansion filter slot? I am sure many of us will welcome such feature. If will ever be such an option but me on alpha/beta testing on top of your list.

Tnx and 73 de VE3GNO Daniel

________________________________
From: Gary Gregory <[hidden email]>
To: "Joe Subich, W4TV" <[hidden email]>
Cc: [hidden email]
Sent: Friday, September 21, 2012 6:19:29 PM
Subject: Re: [Elecraft] New beta K3 firmware!

*Hi Joe,

Thanks for the explanation. I can now 'see' what you meant and it does seem
logical.

I too have all 5 filter slots in use.

'Learning all the time'...:-)

73's Joe and thanks again.

*
On 22 September 2012 07:37, Joe Subich, W4TV <[hidden email]> wrote:

>
> > On Sat, Sep 22, 2012 at 7:00 AM, Gary Gregory <[hidden email]>
> wrote:
> >
> >> I have to ask, why?
>
> Using the FM filter does no widen ESSB or AM ... the bandwidth of
> those modes is determined by the DSP modulator. The only thing
> the 8.215 MHz crystal filter does is to provide some additional
> protection against transmitting the 8.245 MHz image (and according
> to Wayne, provide some additional rejection of very low level
> DSP/mixer noise). In any case, the 13 KHz filter is *still* tight
> enough to eliminate the image - else it could not be used on FM
> either.
>
> In my case, the K3's main RX is "full" of filters - 13 KHz, 2.8,
> 1.8, 400 and 200. I can not use AM or ESSB (if I wanted to) without
> telling the K3 that the 13 KHz filter is really 6 KHz wide. That
> seems to be a significant headache and makes either FM or AM/ESSB
> unusable for those who, like me, have a "full" K3.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 9/21/2012 5:11 PM, Joshua Mesilane wrote:
> > Originally sent direct, was meant for the list.
> >
> >
> > Actually, we can run up to 8khz bandwidth, with the exception of 16Khz in
> > the FM segment of 10m, and of course the very very low band. The rules do
> > change above 10M though depending on your license class. What this means
> is
> > you can actually, legally run 6Khz wide AM on HF.
> >
> > I'm looking at the Amateur LCD right now. It's a common misconception
> that
> > you can only run 3KHz on HF in VK
> >
> > ---
> > VK3XJM
> > 0416039082
> > [hidden email]
> > http://www.zindello.com.au/
> >
> >
> >
> > On Sat, Sep 22, 2012 at 7:00 AM, Gary Gregory <[hidden email]>
> wrote:
> >
> >> *Joe,
> >>
> >> I have to ask, why?
> >>
> >> In VK we have a 3Khz SSB BW written into our LCD's and yet some folks
> >> consume 10Khz out here on a net which tears up a considerable amount of
> >> spectrum.
> >>
> >> What advantage do you see to widen the ESSB?
> >>
> >> Not sure I follow your thoughts here, hence the question Joe.
> >>
> >> 73
> >> *
> >> On 22 September 2012 03:10, Joe Subich, W4TV <[hidden email]> wrote:
> >>
> >>>
> >>> How about allowing use of the FM filter for AM and ESSB transmit?
> >>>
> >>> 73,
> >>>
> >>> ... Joe, W4TV
> >>>
> >>>
> >>> On 9/21/2012 11:11 AM, Wayne Burdick wrote:
> >>>>> Can I ask ELECRAFT what's next on the list for the K3 firmware
> >>>>> improvements we can expect...
> >>>>
> >>>> Hi Gordan,
> >>>>
> >>>> Best guess:
> >>>>
> >>>> - improved CW decode at all AGC settings
> >>>> - support for KAT500 antenna switching from the K3
> >>>> - bug fixes related to remote rig communications (K3/0)
> >>>>
> >>>> There have also been many requests for minor changes, some of which
> >>>> I'll be adding. I can't say yet which ones will make the next cut.
> >>>>
> >>>> 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
> >>>>
> >>> ______________________________________________________________
> >>> 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
> >>>
> >>
> >>
> >>
> >> --
> >> *Gary*
> >> *Start the day off slow, then taper off.........*
> >> K3 #679
> >> KPA500FT #18
> >> KAT500FT 007
> >> P3 #1629
> >> ______________________________________________________________
> >> 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
> >>
> > ______________________________________________________________
> > 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
> >
> ______________________________________________________________
> 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
>

--
*Gary*
*Start the day off slow, then taper off.........*
K3 #679
KPA500FT #18
KAT500FT 007
P3 #1629
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Thomas Horsten

Re: New beta K3 firmware!

Seconded. I would love to have room for an 1.0 (for digimodes) and 200
(weak/QRM CW) filter in addition to my lineup of FM, AM, 2.8, 2.1, and 400.

73, Thomas M0TRN

On 22 September 2012 00:38, VE3GNO Daniel <[hidden email]> wrote:

> Hi All,
>
> I dream one day to see Elecraft building some kind of expansion slot to
> accomodate more filters. Now all my slots are filled, 200/400/2.1k/2.8k/FM
> x2 for both RXs so no more free slots for AM or any other filter. I don't
> care too much abt AM filter but I would like to squeeze two more filters,
> maybe a 800 and 1.5k filter. Wayne, do you see technical possible to
> accomodate some sort of optional expansion filter slot? I am sure many of
> us will welcome such feature. If will ever be such an option but me on
> alpha/beta testing on top of your list.
>
> Tnx and 73 de VE3GNO Daniel
>

Phil Shepard

KPA500 Problem

I put my new KPA500 (s/n 1057) together earlier this week and have been
loving it, although it has seen only light use so far.

However, that changed this afternoon. I used it briefly on 40m LSB a few
hours ago and all was fine. About 35w of drive for 550w out. I just
retuned the antenna to the low end of the band, yielding a 1.0:1 SWR at the
K3 in the standby mode of the KPA500. When I switched the amp to operate
and keyed the transmitter (tune control), the amp power LEDs jumped up to
about 500w and then went to 0. Subsequent keying show a very high SWR at
the K3 (65 to 99:1) and the K3 puts out no power as does the KPA500. I
tried a dummy load with the same result. If the amp is in standby mode the
K3 acts right and the power and SWR LEDs on the KPA500 act right (100w out
at a low SWR). Putting the amp into operate mode acts like the input SWR is
very high.

I tried tightening up the cables at both ends (BTW, I am using the control
cable between the rig and amp for maximum integration, and the K3 knows to
reduce the power out when the amp is in operate).

I hope I am doing something wrong, and the fix is simple. Any suggestions
of where to begin? Thank you.

73,
Phil, NS7P

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Scott Manthe-2

Re: KPA500 Problem

Is this behavior present on all bands or just 40 meters? You might try
using the KPA500 without the control cable, as well.

73,
Scott, N9AA

On 9/21/12 8:01 PM, Phillip Shepard wrote:

> I put my new KPA500 (s/n 1057) together earlier this week and have been
> loving it, although it has seen only light use so far.
>
> However, that changed this afternoon. I used it briefly on 40m LSB a few
> hours ago and all was fine. About 35w of drive for 550w out. I just
> retuned the antenna to the low end of the band, yielding a 1.0:1 SWR at the
> K3 in the standby mode of the KPA500. When I switched the amp to operate
> and keyed the transmitter (tune control), the amp power LEDs jumped up to
> about 500w and then went to 0. Subsequent keying show a very high SWR at
> the K3 (65 to 99:1) and the K3 puts out no power as does the KPA500. I
> tried a dummy load with the same result. If the amp is in standby mode the
> K3 acts right and the power and SWR LEDs on the KPA500 act right (100w out
> at a low SWR). Putting the amp into operate mode acts like the input SWR is
> very high.
>
> I tried tightening up the cables at both ends (BTW, I am using the control
> cable between the rig and amp for maximum integration, and the K3 knows to
> reduce the power out when the amp is in operate).
>
> I hope I am doing something wrong, and the fix is simple. Any suggestions
> of where to begin? Thank you.
>
> 73,
> Phil, NS7P
>
>

wayne burdick

Re: New beta K3 firmware!

Administrator

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

Maybe I'll put the feature in and let you be my guinea pig, Joe. One
complaint about noise bandwidth and it comes back out ;)

Wayne

On Sep 21, 2012, at 4:20 PM, Joe Subich, W4TV wrote:

>
>> This in-band noise "pedestal" could be 20-30 dB above the normal
>> transmit noise floor if you were using a lot of mic gain and/or
>> compression. If you were using high power in these modes, your signal
>> would now be much more likely to bring up the receive noise floor at
>> nearby stations.
>
> It would seem that the same argument would be made against using the
> 2.7 or 2.8 KHz filters for CW or digital modes that have a transmit
> bandwidth of 50 to 100 Hz. Why generate an excessively wide 3 KHz
> noise
> pedestal for CW or PSK31/63 or even FSK RTTY (300 Hz required)?
>
> This is all academic since it is easy - although very inconvenient -
> to
> set FL1 BW to 6.00 with the FM filter to enable AM/ESSB and return it
> to 13.00 to go back to FM.
>
> The real issue is that any user with three "narrow" filters for SSB
> and
> CW/Digital is precluded from using both FM and AM/ESSB without playing
> games with FL1 BW.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 9/21/2012 6:40 PM, Wayne Burdick wrote:
>> The 6 kHz filter band-limits the transmit noise originating from the
>> DAC and the transmit mixer to a bandwidth appropriate for AM and ESSB
>> modes. The 15 kHz filter would allow a noise bandwidth over twice as
>> wide.
>>
>> This in-band noise "pedestal" could be 20-30 dB above the normal
>> transmit noise floor if you were using a lot of mic gain and/or
>> compression. If you were using high power in these modes, your signal
>> would now be much more likely to bring up the receive noise floor at
>> nearby stations.
>>
>> Do you really want to create a 15-kHz wide swath of broadband noise
>> when using ESSB or AM?
>>
>> I don't. That's why I haven't modified the code to allow use of the
>> FM
>> filter for this purpose. I suppose it could be YAMU (yet another menu
>> entry), forcing you to do at least a minimum amount of soul-searching
>> before "going broadband" :)
>>
>> 73,
>> Wayne
>> N6KR
>>
>>
>> On Sep 21, 2012, at 3:09 PM, Thomas Horsten wrote:
>>
>>> Hi Gary,
>>>
>>> The point is not to widen the SSB but to use the FM crystal filter
>>> to limit
>>> it. The DSP does the actual shaping of the TX signal which will
>>> still be
>>> the same width regardless of whether you're using the 6kHz filter or
>>> the
>>> 12.5kHz FM one.
>>>
>>> The idea is to be able to use the FM filter for AM and ESSB as well
>>> instead
>>> of filling up two precious filter slots, when what you may want/need
>>> are
>>> closer filters on the low end (say, 400 and 200 Hz).
>>>
>>> 73, Thomas M0TRN
>>>
>>> On 21 September 2012 22:00, Gary Gregory <[hidden email]>
>>> wrote:
>>>
>>>> Joe,
>>>>
>>>> I have to ask, why?
>>>>
>>>> In VK we have a 3Khz SSB BW written into our LCD's and yet some
>>>> folks
>>>> consume 10Khz out here on a net which tears up a considerable
>>>> amount of
>>>> spectrum.
>>>>
>>>> What advantage do you see to widen the ESSB?
>>>>
>>>> Not sure I follow your thoughts here, hence the question Joe.
>>>>
>>>> 73
>>>>
>>> ______________________________________________________________
>>> 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
>>
>> ______________________________________________________________
>> 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
>>
> ______________________________________________________________
> 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

Scott Manthe-2

Re: New beta K3 firmware!

In reply to this post by Thomas Horsten

My feeling is that if you have the 8 pole 2.8 kHz filter installed, the
2.1 kHz filter is probably redundant for vast majority of applications.

73,
Scott, N9AA

> Seconded. I would love to have room for an 1.0 (for digimodes) and 200
> (weak/QRM CW) filter in addition to my lineup of FM, AM, 2.8, 2.1, and 400.
>
> 73, Thomas M0TRN
>
> On 22 September 2012 00:38, VE3GNO Daniel <[hidden email]> wrote:
>
>> Hi All,
>>
>> I dream one day to see Elecraft building some kind of expansion slot to
>> accomodate more filters. Now all my slots are filled, 200/400/2.1k/2.8k/FM
>> x2 for both RXs so no more free slots for AM or any other filter. I don't
>> care too much abt AM filter but I would like to squeeze two more filters,
>> maybe a 800 and 1.5k filter. Wayne, do you see technical possible to
>> accomodate some sort of optional expansion filter slot? I am sure many of
>> us will welcome such feature. If will ever be such an option but me on
>> alpha/beta testing on top of your list.
>>
>> Tnx and 73 de VE3GNO Daniel
>>

vk4tux

Re: New beta K3 firmware!

In reply to this post by E72X

I couldnt disagree more, I use the 2.1k most followed by the 1.8k in
ssb. I never see/hear a need to go wider than 2.1k other than to
appreciate Johnny Broadcasters new $1000 studio mic. I use the 2.8k std
req for TX. On 22/09/2012 1:59, Scott Manthe wrote: > My feeling is that
if you have the 8 pole 2.8 kHz filter installed, the > 2.1 kHz filter is
probably redundant for vast majority of applications. > > 73, > Scott,
N9AA > > >> Seconded. I would love to have room for an 1.0 (for
digimodes) and 200 >> (weak/QRM CW) filter in addition to my lineup of
FM, AM, 2.8, 2.1, and 400. >> >> 73, Thomas M0TRN >> >> On 22 September
2012 00:38, VE3GNO Daniel<[hidden email]> wrote: >> >>> Hi All, >>>
>>> I dream one day to see Elecraft building some kind of expansion
slot to >>> accomodate more filters. Now all my slots are filled,
200/400/2.1k/2.8k/FM >>> x2 for both RXs so no more free slots for AM or
any other filter. I don't >>> care too much abt AM filter but I would
like to squeeze two more filters, >>> maybe a 800 and 1.5k filter.
Wayne, do you see technical possible to >>> accomodate some sort of
optional expansion filter slot? I am sure many of >>> us will welcome
such feature. If will ever be such an option but me on >>> alpha/beta
testing on top of your list. >>> >>> Tnx and 73 de VE3GNO Daniel >>> >
______________________________________________________________ >
Elecraft mailing list > Home:
http://mailman.qth.net/mailman/listinfo/elecraft > Help:
http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email]
> > This list hosted by: http://www.qsl.net > Please help support this
email list: http://www.qsl.net/donate.html >
______________________________________________________________
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AJ8MH-Radio.Joe.Hutchens

Re: KPA500 Problem

In reply to this post by Phil Shepard

Did you find your problem? Any fault codes?

I suggest contacting [hidden email], but if were me, I'd check all
internal connections first and do a quick visual. I suspect a problem
with the elaborate TR switching circuit or something that controls it.

I see a couple 51 ohm resistors on the schematic at the input to the PA
module, so if the TR switch was working, I would NOT expect hi reflected
power to the rig with no power out of the AMP.

Joe Hutchens ( AJ8MH )
http://webpages.charter.net/aj8mh-radio/

On Fri, Sep 21, 2012 at 8:01 PM, Phillip Shepard wrote:

> I put my new KPA500 (s/n 1057) together earlier this week and have
> been
> loving it, although it has seen only light use so far.
>
> However, that changed this afternoon. I used it briefly on 40m LSB a
> few
> hours ago and all was fine. About 35w of drive for 550w out. I just
> retuned the antenna to the low end of the band, yielding a 1.0:1 SWR
> at the
> K3 in the standby mode of the KPA500. When I switched the amp to
> operate
> and keyed the transmitter (tune control), the amp power LEDs jumped up
> to
> about 500w and then went to 0. Subsequent keying show a very high
> SWR at
> the K3 (65 to 99:1) and the K3 puts out no power as does the KPA500.
> I
> tried a dummy load with the same result. If the amp is in standby
> mode the
> K3 acts right and the power and SWR LEDs on the KPA500 act right (100w
> out
> at a low SWR). Putting the amp into operate mode acts like the input
> SWR is
> very high.
>
> I tried tightening up the cables at both ends (BTW, I am using the
> control
> cable between the rig and amp for maximum integration, and the K3
> knows to
> reduce the power out when the amp is in operate).
>
> I hope I am doing something wrong, and the fix is simple. Any
> suggestions
> of where to begin? Thank you.
>
> 73,
> Phil, NS7P
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

Joe Subich, W4TV-4

Re: New beta K3 firmware!

In reply to this post by wayne burdick

On 9/21/2012 6:40 PM, Wayne Burdick wrote:
> The 6 kHz filter band-limits the transmit noise originating from the
> DAC and the transmit mixer to a bandwidth appropriate for AM and ESSB
> modes. The 15 kHz filter would allow a noise bandwidth over twice as
> wide.

In an attempt to quantify this wideband transmit noise, I set up the
K3 on the test bench with a dummy load, directional coupler, some
attenuators, another receiver and the SDR-IQ. The directional coupler
provided a 1 dBm signal with 100W from the K3.

1) I measured the "in band" noise (noise in the transmit bandwidth)
-80 dB relative to 100W output. That is, when the sample was
applied directly to the test receiver, the noise pedestal *within*
the normal SSB or ESSB bandwidth is ~S8. "Out of band" (opposite
sideband) noise or noise more than 3 to 4 KHz above carrier is at
least -100 to -110 dB below PEP (20 to 30 dB below the in band
noise).

Note: all tests were performed with the microphone unplugged but
the mic gain at normal levels and compression set to approximately
15 dB compression (normal operating conditions).

2) In SSB (with the 2.8 KHz roofing filter) the in band noise is
roughly 3 KHz wide based on tuning a receiver until the noise
drops below MDS (-147 dBm measured) or looking at the spectrum
using the SDR-IQ. The out of band noise extends about 1 KHz
below Fc (measurements were made on 20 meters USB) and is at
least 20 dB below the in band noise level.

3) In ESSB/4.0 KHz (with the FM roofing filter) the in band noise
measured 4.5 KHz wide with the receiver and/or SDR-IQ. The LSB
noise is 20 to 30 dB below the in band noise level and extends
about 4 KHz below Fc.

In either case, the "out of band" noise is at least -100 dB relative
to PEP and is likely to produce detectable QRM only to the closest
of neighbors with high power operation and even then only within
5 KHz on the opposite sideband.

For grins, I looked at the in band/out of band (opposite sideband)
noise of a conventional up conversion (Icom) transceiver that I had
on the test bench. The in band noise pedestal was also around -80
dB/PEP with out of band (lower sideband) noise about 20 to 30 dB
below the in band level extending 3 KHz below Fc.

In summary, while using a narrow filter (2.8 KHz for normal SSB,
6 KHz for AM/ESSB) will reduce the "out of band" products somewhat,
using the FM filter results in a signal that is comparable with
"conventional" transceivers. Based on experience with conventional
up conversion transceivers, the effects of the opposite sideband noise
are generally *less* than those from AGC pumping or transmitted phase
noise. Anyone who would complain about transmit noise when the K3
is using an FM filter for ESSB/AM would have the same complaint with
a conventional transceiver.

One further note, "opposite sideband noise" was slightly lower in
DATA A (and AFSK A) than in USB - perhaps due to changes in filter
offset. However, the -80 dB/PEP in-band noise pedestal was still
present for the full 3 KHz bandwidth.

73,

... Joe, W4TV

On 9/21/2012 6:40 PM, Wayne Burdick wrote:

> The 6 kHz filter band-limits the transmit noise originating from the
> DAC and the transmit mixer to a bandwidth appropriate for AM and ESSB
> modes. The 15 kHz filter would allow a noise bandwidth over twice as
> wide.
>
> This in-band noise "pedestal" could be 20-30 dB above the normal
> transmit noise floor if you were using a lot of mic gain and/or
> compression. If you were using high power in these modes, your signal
> would now be much more likely to bring up the receive noise floor at
> nearby stations.
>
> Do you really want to create a 15-kHz wide swath of broadband noise
> when using ESSB or AM?
>
> I don't. That's why I haven't modified the code to allow use of the FM
> filter for this purpose. I suppose it could be YAMU (yet another menu
> entry), forcing you to do at least a minimum amount of soul-searching
> before "going broadband" :)
>
> 73,
> Wayne
> N6KR
>
>

k6dgw

Re: KPA500 Problem

In reply to this post by Phil Shepard

On 9/21/2012 5:01 PM, Phillip Shepard wrote:

> I tried tightening up the cables at both ends (BTW, I am using the control
> cable between the rig and amp for maximum integration, and the K3 knows to
> reduce the power out when the amp is in operate).

That is not totally true, for me at least. I went through all bands and
set up the power with and without the KPA500. 99% of the time, going
anywhere with the KPA500 in stby, I get 100W from the K3. 97% of the
time, then going to oper, I get 500W from the KPA500.

Roughly 3% of the time, after tuning the external ant coupler [REALLY
anxious for the KAT500!], putting the amp in oper gives me TUNE pwr [5W
for me] from the K3, and around 60 W from the 500. So far, the only way
I've found to get it back to normal is to rotate the PWR knob back to 27
or so watts.

1% of the time, or even less, going to oper on the KPA500 leaves the K3
power at 100W. First tap on the paddle lights everything up, and it
shuts down with the fault light on. On a couple of occasions, I have
had to unplug the KPA500 for a minute or so. None of this is
reproducible, at least in the time I'm willing to spend trying to
reproduce it. It just happens, sort of on every third Thursday after
the first full moon after the equinox.

I would really like the display B messages on the K3 to show the power
it is going to transmit with the next time I tap the paddle when the
KPA500 switches between STBY and OPER. I have my KPA500 set to go to
STBY on band change so this is a fairly frequent activity.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

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vk4tux

Re: New beta K3 firmware!

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

Thankyou Joe, Excellent examination of the situation.

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Joe Subich, W4TV
Sent: Sunday, 23 September 2012 12:23 AM
To: [hidden email]
Subject: Re: [Elecraft] New beta K3 firmware!

On 9/21/2012 6:40 PM, Wayne Burdick wrote:
> The 6 kHz filter band-limits the transmit noise originating from the >
DAC and the transmit mixer to a bandwidth appropriate for AM and ESSB >
modes. The 15 kHz filter would allow a noise bandwidth over twice as >
wide.

In an attempt to quantify this wideband transmit noise, I set up the
K3 on the test bench with a dummy load, directional coupler, some
attenuators, another receiver and the SDR-IQ. The directional coupler
provided a 1 dBm signal with 100W from the K3.

1) I measured the "in band" noise (noise in the transmit bandwidth)
-80 dB relative to 100W output. That is, when the sample was
applied directly to the test receiver, the noise pedestal *within*
the normal SSB or ESSB bandwidth is ~S8. "Out of band" (opposite
sideband) noise or noise more than 3 to 4 KHz above carrier is at
least -100 to -110 dB below PEP (20 to 30 dB below the in band
noise).

Note: all tests were performed with the microphone unplugged but
the mic gain at normal levels and compression set to approximately
15 dB compression (normal operating conditions).

2) In SSB (with the 2.8 KHz roofing filter) the in band noise is
roughly 3 KHz wide based on tuning a receiver until the noise
drops below MDS (-147 dBm measured) or looking at the spectrum
using the SDR-IQ. The out of band noise extends about 1 KHz
below Fc (measurements were made on 20 meters USB) and is at
least 20 dB below the in band noise level.

3) In ESSB/4.0 KHz (with the FM roofing filter) the in band noise
measured 4.5 KHz wide with the receiver and/or SDR-IQ. The LSB
noise is 20 to 30 dB below the in band noise level and extends
about 4 KHz below Fc.

In either case, the "out of band" noise is at least -100 dB relative to PEP
and is likely to produce detectable QRM only to the closest of neighbors
with high power operation and even then only within
5 KHz on the opposite sideband.

For grins, I looked at the in band/out of band (opposite sideband) noise of
a conventional up conversion (Icom) transceiver that I had on the test
bench. The in band noise pedestal was also around -80 dB/PEP with out of
band (lower sideband) noise about 20 to 30 dB below the in band level
extending 3 KHz below Fc.

In summary, while using a narrow filter (2.8 KHz for normal SSB,
6 KHz for AM/ESSB) will reduce the "out of band" products somewhat, using
the FM filter results in a signal that is comparable with "conventional"
transceivers. Based on experience with conventional up conversion
transceivers, the effects of the opposite sideband noise are generally
*less* than those from AGC pumping or transmitted phase noise. Anyone who
would complain about transmit noise when the K3 is using an FM filter for
ESSB/AM would have the same complaint with a conventional transceiver.

One further note, "opposite sideband noise" was slightly lower in DATA A
(and AFSK A) than in USB - perhaps due to changes in filter offset.
However, the -80 dB/PEP in-band noise pedestal was still present for the
full 3 KHz bandwidth.

73,

... Joe, W4TV

On 9/21/2012 6:40 PM, Wayne Burdick wrote:

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Thomas Horsten

Re: New beta K3 firmware!

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

Hi Joe,

Thanks for that analysis! It makes the situation clear to me: The FM filter
will do just fine for AM and ESSB, and I can free up a filter slot for a
narrow CW filter.

Wayne, it would be great to have this option. I hardly ever use ESSB or AM
TX, so I can't really justify having a filter just for that if it means I'm
missing out a on 200Hz CW filter that would be really useful at times.

73, Thomas M0TRN

On 22 September 2012 15:23, Joe Subich, W4TV <[hidden email]> wrote:

> In an attempt to quantify this wideband transmit noise, I set up the
> K3 on the test bench with a dummy load, directional coupler, some
> attenuators, another receiver and the SDR-IQ. The directional coupler
> provided a 1 dBm signal with 100W from the K3.
>
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Gary Gregory

Re: New beta K3 firmware!

*Joe,

Thanks for taking the time to conduct the tests.

Now that I understand what the rationale for the request to Wayne, I am of
the same mind also.

As I use the FM filter rarely I would also be able to free up a filter slot
and add an additional narrow filter which would be good for me also.

I hope Wayne will give consideration to your request in light of your
testing and implement it soon.

Thanks again Joe for the test results and the reasoning for the request.

73
*
On 23 September 2012 08:02, Thomas Horsten <[hidden email]> wrote:

> Hi Joe,
>
> Thanks for that analysis! It makes the situation clear to me: The FM filter
> will do just fine for AM and ESSB, and I can free up a filter slot for a
> narrow CW filter.
>
> Wayne, it would be great to have this option. I hardly ever use ESSB or AM
> TX, so I can't really justify having a filter just for that if it means I'm
> missing out a on 200Hz CW filter that would be really useful at times.
>
> 73, Thomas M0TRN
>
> On 22 September 2012 15:23, Joe Subich, W4TV <[hidden email]> wrote:
>
> > In an attempt to quantify this wideband transmit noise, I set up the
> > K3 on the test bench with a dummy load, directional coupler, some
> > attenuators, another receiver and the SDR-IQ. The directional coupler
> > provided a 1 dBm signal with 100W from the K3.
> >
> ______________________________________________________________
> 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
>

Don Wilhelm-4

Re: New beta K3 firmware!

Gary,

Joe did testing on a sample size of one K3. While manufacturing of K3s
can produce units that behave close to the average, I think it would be
wise to test on a greater number of K3s with different configurations.
In addition some testing of K3s under fault conditions should be done too.

73,
Don W3FPR

On 9/22/2012 6:13 PM, Gary Gregory wrote:

> *Joe,
>
> Thanks for taking the time to conduct the tests.
>
> Now that I understand what the rationale for the request to Wayne, I am of
> the same mind also.
>
> As I use the FM filter rarely I would also be able to free up a filter slot
> and add an additional narrow filter which would be good for me also.
>
> I hope Wayne will give consideration to your request in light of your
> testing and implement it soon.
>
> Thanks again Joe for the test results and the reasoning for the request.
>
> 73
> *
> On 23 September 2012 08:02, Thomas Horsten <[hidden email]> wrote:
>
>> Hi Joe,
>>
>> Thanks for that analysis! It makes the situation clear to me: The FM filter
>> will do just fine for AM and ESSB, and I can free up a filter slot for a
>> narrow CW filter.
>>

Scott Manthe-2

Re: New beta K3 firmware!

It might also be interesting to see what happens to the "noise pedestal"
when audio is added to the equation.

73,
Scott, N9AA

On 9/22/12 6:31 PM, Don Wilhelm wrote:

> Gary,
>
> Joe did testing on a sample size of one K3. While manufacturing of K3s
> can produce units that behave close to the average, I think it would be
> wise to test on a greater number of K3s with different configurations.
> In addition some testing of K3s under fault conditions should be done too.
>
> 73,
> Don W3FPR
>
> On 9/22/2012 6:13 PM, Gary Gregory wrote:
>> *Joe,
>>
>> Thanks for taking the time to conduct the tests.
>>
>> Now that I understand what the rationale for the request to Wayne, I am of
>> the same mind also.
>>
>> As I use the FM filter rarely I would also be able to free up a filter slot
>> and add an additional narrow filter which would be good for me also.
>>
>> I hope Wayne will give consideration to your request in light of your
>> testing and implement it soon.
>>
>> Thanks again Joe for the test results and the reasoning for the request.
>>
>> 73
>> *
>> On 23 September 2012 08:02, Thomas Horsten <[hidden email]> wrote:
>>
>>> Hi Joe,
>>>
>>> Thanks for that analysis! It makes the situation clear to me: The FM filter
>>> will do just fine for AM and ESSB, and I can free up a filter slot for a
>>> narrow CW filter.
>>>
>

k6dgw

Re: KPA500 Problem

In reply to this post by k6dgw

On 9/22/2012 3:05 PM, Bill K9YEQ wrote:
> Fred,
>
> More than likely you are changing freqs and the amplifier/K3 are folding
> back power based on detected antenna complex loading issues. Until the
> KAT500 becomes available, you don't need 100 watts on any band to get 500W
> out! Back off your per band settings and test. Whatever you are using for
> your tuner, I would suspect it is not matching.

I think I wasn't clear Bill, and unfortunately, it's not the first time.
:-) The KPA500 wants between 25 and 30 watts, depending on band for 500
watts out. The irreproducible "problem" I described seems to be in the
dual-power memories in the K3. The most common manifestation is:

1. KPA500 --> STBY, usually because I punched up a new band on it.

2. K3 TUNE: Mine is 5W. I tune up the antenna coupler [MFJ 989-C],
SWR=1:1

3. KPA500 --> OPER, because I pressed the switch

4. K3 TUNE: SWR still 1:1, but now into the KPA500 of course, output
power around 60W [still 5W tune power from the K3]

5. Tap K3 TUNE, now I'm receiving and ready to TX. KPA500 is in OPER.
K3 should have gone to 25-30W depending on the band. Start to send,
KPA500 output is still around 60W [and the DX calls someone else], and
when I move the K3 PWR knob to check the setting, it is still at 5W.
The only way I've found to get it back to the 25-30W range is to turn
the PWR knob.

This only happens every now and then, more often then than now, nearly
all the time it works as expected ... ending TUNE on the K3 sets the
power to 25-30W if the KPA500 is in OPER, 100W if it isn't. If I had to
guess [hardly ever a productive troubleshooting technique], it looks
like the power memories are fine, the K3 is just missing some signal to
tell it to go into normal operate mode with an active KPA500.

The reverse problem ... running barefoot at 100W and I put the KPA500
into OPER [using the front panel switch] because the DX isn't answering
me [and I'm going to show these clods in the pile!] and the K3 stays at
100W [lighting up the 500 :-)] has happened a few times, not nearly as
often as the reverse problem described above.

I've tried re-seating the big cable between the KPA500 and K3 several
times, once with a drop of DeOxit into the contacts, with essentially no
change.

Since I can't make it happen on command, I'm loath to do much more than
mention it here, and maybe should stop that. I sent my K2 to Don once
with what I perceived as a clear problem, he spent a lot of time for
which I'm sure he did not charge me, and couldn't make it fail. It's
never happened again, in fact I managed NH8S just before QRT with K2 @
5W to my new AlexLoop out on our deck.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

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AC6JA

Re: KPA500 Problem

In reply to this post by Phil Shepard

Fred,
There is a known firmware issue which causes the K3 to sometimes "forget"
to go back to 100W when switching the KPA500 from OPER to STBY.
Mine has the same issue where I need to periodically reset the K3 PWR back
up to 100W when operating the KPA500 in STBY. So far the K3 remembers to
go to the preset PWR output levels when the KPA500 is in OPER.
Elecraft is supposed to address this issue in a future firmware release.

Mike AC6JA

In a message dated 9/22/2012 4:31:41 P.M. Pacific Daylight Time,
[hidden email] writes:

On 9/22/2012 3:05 PM, Bill K9YEQ wrote:
> Fred,
>
> More than likely you are changing freqs and the amplifier/K3 are folding
> back power based on detected antenna complex loading issues. Until the
> KAT500 becomes available, you don't need 100 watts on any band to get
500W
> out! Back off your per band settings and test. Whatever you are using
for
> your tuner, I would suspect it is not matching.

I think I wasn't clear Bill, and unfortunately, it's not the first time.
:-) The KPA500 wants between 25 and 30 watts, depending on band for 500
watts out. The irreproducible "problem" I described seems to be in the
dual-power memories in the K3. The most common manifestation is:

1. KPA500 --> STBY, usually because I punched up a new band on it.

2. K3 TUNE: Mine is 5W. I tune up the antenna coupler [MFJ 989-C],
SWR=1:1

3. KPA500 --> OPER, because I pressed the switch

4. K3 TUNE: SWR still 1:1, but now into the KPA500 of course, output
power around 60W [still 5W tune power from the K3]

5. Tap K3 TUNE, now I'm receiving and ready to TX. KPA500 is in OPER.
K3 should have gone to 25-30W depending on the band. Start to send,
KPA500 output is still around 60W [and the DX calls someone else], and
when I move the K3 PWR knob to check the setting, it is still at 5W.
The only way I've found to get it back to the 25-30W range is to turn
the PWR knob.

This only happens every now and then, more often then than now, nearly
all the time it works as expected ... ending TUNE on the K3 sets the
power to 25-30W if the KPA500 is in OPER, 100W if it isn't. If I had to
guess [hardly ever a productive troubleshooting technique], it looks
like the power memories are fine, the K3 is just missing some signal to
tell it to go into normal operate mode with an active KPA500.

The reverse problem ... running barefoot at 100W and I put the KPA500
into OPER [using the front panel switch] because the DX isn't answering
me [and I'm going to show these clods in the pile!] and the K3 stays at
100W [lighting up the 500 :-)] has happened a few times, not nearly as
often as the reverse problem described above.

I've tried re-seating the big cable between the KPA500 and K3 several
times, once with a drop of DeOxit into the contacts, with essentially no
change.

Since I can't make it happen on command, I'm loath to do much more than
mention it here, and maybe should stop that. I sent my K2 to Don once
with what I perceived as a clear problem, he spent a lot of time for
which I'm sure he did not charge me, and couldn't make it fail. It's
never happened again, in fact I managed NH8S just before QRT with K2 @
5W to my new AlexLoop out on our deck.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org

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Bob Cunnings NW8L

Re: KPA500 Problem

In reply to this post by Phil Shepard

I experience a similar thing. With KPA500 BAND CHG set to STBY and
using the KPA500 band buttons to change bands, it happens if the
KPA500 goes from OPER to STBY on band change. Elecraft support
confirmed the issue and said that it would be fixed in the next K3
firmware release.

Bob NW8L

>Fred,
>There is a known firmware issue which causes the K3 to sometimes "forget"
>to go back to 100W when switching the KPA500 from OPER to STBY.
>Mine has the same issue where I need to periodically reset the K3 PWR back
>up to 100W when operating the KPA500 in STBY. So far the K3 remembers to
>go to the preset PWR output levels when the KPA500 is in OPER.
>Elecraft is supposed to address this issue in a future firmware release.
>
>Mike AC6JA
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Joe Subich, W4TV-4

Re: New beta K3 firmware!

In reply to this post by Scott Manthe-2

It would be very difficult to measure the out of band noise in the
presence of a 100W PEP multi-tone audio signal. Much of the opposite
sideband noise would be masked by amplifier IMD which measures -29 dB
(3rd order) to -51 dB (9th order) relative to PEP in the ARRL lab (QST,
January, 2009). In addition, one would need some very selective filters
to reduce the 100 W PEP signal to a level that would allow measuring
the out of band (opposite sideband) noise as 100 dB is pushing the range
of many spectrum analyzers. In any case, since the "in band"
pedestal is present with no audio, one can assume any out of band noise
is also generated with no audio.

Don, you can consider my results a sample of two ... although I did not
repeat all the tests, my other K3 looks slightly *better* than the one
I reported on.

Again, the point is that although opposite sideband rejection is
better with the narrow filter, even with the FM filter is it (1) no
worse than a conventional transceiver, (2) better than transmit IMD
from the final amplifier and (3) better than the transmitted phase
noise from many rigs. Note opposite sideband suppression in many
older rigs is in the -65 to -75 dB range (ARRL "Expanded Test Report")
vs. an effective opposite sideband suppression in excess of 100 dB for
the K3.

73,

... Joe, W4TV

On 9/22/2012 6:49 PM, Scott Manthe wrote:

> It might also be interesting to see what happens to the "noise pedestal"
> when audio is added to the equation.
>
> 73,
> Scott, N9AA
>
>
> On 9/22/12 6:31 PM, Don Wilhelm wrote:
>> Gary,
>>
>> Joe did testing on a sample size of one K3. While manufacturing of K3s
>> can produce units that behave close to the average, I think it would be
>> wise to test on a greater number of K3s with different configurations.
>> In addition some testing of K3s under fault conditions should be done too.
>>
>> 73,
>> Don W3FPR
>>
>> On 9/22/2012 6:13 PM, Gary Gregory wrote:
>>> *Joe,
>>>
>>> Thanks for taking the time to conduct the tests.
>>>
>>> Now that I understand what the rationale for the request to Wayne, I am of
>>> the same mind also.
>>>
>>> As I use the FM filter rarely I would also be able to free up a filter slot
>>> and add an additional narrow filter which would be good for me also.
>>>
>>> I hope Wayne will give consideration to your request in light of your
>>> testing and implement it soon.
>>>
>>> Thanks again Joe for the test results and the reasoning for the request.
>>>
>>> 73
>>> *
>>> On 23 September 2012 08:02, Thomas Horsten <[hidden email]> wrote:
>>>
>>>> Hi Joe,
>>>>
>>>> Thanks for that analysis! It makes the situation clear to me: The FM filter
>>>> will do just fine for AM and ESSB, and I can free up a filter slot for a
>>>> narrow CW filter.
>>>>
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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>

Don Wilhelm-4

Re: New beta K3 firmware!

Joe,

That information on the sample of two is good, but since there is
variation between them, that is reason for me to suggest additional
testing - it takes 3 to "vote" on the correct answer and several more to
determine an average.

Joe, that was very good work, and the test setup is not trivial. Yes
proper tests at 100 watt PEP would require a lot of careful thought for
the exact setup and some very good filters.

I too would like to see the FM filter also usable for AM and ESSB. I
really never anticipate transmitting in AM or ESSB, there is always the
possibility I would like to use it for some demo sessions showing off
the K3 capabilities. The cost/benefit ratio is too high for that kind
of occasional application.

73,
Don W3FPR

On 9/22/2012 8:40 PM, Joe Subich, W4TV wrote:
> Don, you can consider my results a sample of two ... although I did not
> repeat all the tests, my other K3 looks slightly *better* than the one
> I reported on.
>

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123