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[K3] Passband tuning quirk

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ab2tc

[K3] Passband tuning quirk

Hi all,

Operating in the WAE contest I am experiencing a quirk with the passband control knobs and displays that I haven't noticed before. My operating habit in SSB is to use the HiCut/LoCut mode, generally leaving the LoCut at 300Hz and use the HiCut as a QRM fighting tool. This works beautifully for me. If I am in doubt what my current passband is, I press either button twice to see what its setting is. Here is where the quirk comes in. I am currently working with a passband of 300-2300 Hz, at least that what the buttons report after the 2nd press. But after the first press the HI/WIDTH button reports a BW of 2050Hz which is off by 50Hz. My firmware version is 4.05 / 2.60. This, of course is no big deal, but I wish after more than two years of firmware upgrades we could get this perfected. There are still problems with the graphic representation of the passband so that can't be relied upon either.

AB2TC - Knut

Guy, K2AV

Re: [K3] Passband tuning quirk

I have beta firmware 4.10 and I just went through your procedure
below. Mine tracks correctly. I get the correct numbers. I seem to
recall some text about what you report some while back, so it seems it
has had some attention paid to it. Does not sound like it's keeping
you from hearing anything or adjusting it. But you can try the beta
version:

ftp://ftp.elecraft.com/K3/firmware/beta/k3fw4r10.zip

73, Guy.

On Sat, Sep 11, 2010 at 4:17 PM, ab2tc <[hidden email]> wrote:

>
> Hi all,
>
> Operating in the WAE contest I am experiencing a quirk with the passband
> control knobs and displays that I haven't noticed before. My operating habit
> in SSB is to use the HiCut/LoCut mode, generally leaving the LoCut at 300Hz
> and use the HiCut as a QRM fighting tool. This works beautifully for me. If
> I am in doubt what my current passband is, I press either button twice to
> see what its setting is. Here is where the quirk comes in. I am currently
> working with a passband of 300-2300 Hz, at least that what the buttons
> report after the 2nd press. But after the first press the HI/WIDTH button
> reports a BW of 2050Hz which is off by 50Hz. My firmware version is 4.05 /
> 2.60. This, of course is no big deal, but I wish after more than two years
> of firmware upgrades we could get this perfected. There are still problems
> with the graphic representation of the passband so that can't be relied upon
> either.
>
> AB2TC - Knut
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/K3-Passband-tuning-quirk-tp5522141p5522141.html
> Sent from the [K3] mailing list archive at Nabble.com.
> ______________________________________________________________
> 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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wb2ssb

P3 Misbehaving?

Just assembled P3 a few days ago. Having a problem that I can't seem to solve.

Background: Haven't done K3 OUT mod yet (SN 113 ---- fairly old) ... really am apprehensive about opening up K3 again ... but I know I'm just being neurotic ... will face any weekend now).

The P3 was pretty much performing as expected ... given that I haven't done the above mode yet, and I live in manhattan with a mediocre hamstick hung outside my window .. I could generally see strongest stations above a lot of noise on P3. That was good.

But over past few days, it seems that the sensitivity of the device was diminishing .. started to have trouble seeing the few stations that I could actually hear above the noise on my K3 ... and then today, it now appears that the P3 is basically deaf to the K3 ... I see some low ampitude noise, which doesn't vary in appearance with or without the coax cable to the IF OUT of the K3 plugged in. I am listening to a fairly strong Italian CW station now on 20 meters now, sticking his head above the omnipresent S5-6 noise ... armchair copy, if you will, but all I see is noise at the bottom of the P3 screen. The center frequency tracks my K3 nicely ... but no matter how I adjust the REF, SCALE and SPAN, all I see is noise.

Any thoughts would be welcome. Yes, I will dive in and do the IF OUT mod, but am trying to understand the curious behavior, and to see if it sounds familiar to anyone.

Thanks in advance

-- WB2SSB

Joseph J. Sanger, M.D.
Associate Professor of Radiology
Director, Radiology Informatics

------------------------------------------------------------
This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this email.
=================================

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Matt Zilmer

Re: P3 Misbehaving?

Idea: Change in propagation causes different band noise levels. Same
with geomagnetic activity, number of neighbors in the building, you
name it.

matt W6NIA
K3 #24
P3 #14

On Sat, 11 Sep 2010 18:34:26 -0400, you wrote:

>Just assembled P3 a few days ago. Having a problem that I can't seem to solve.
>
>Background: Haven't done K3 OUT mod yet (SN 113 ---- fairly old) ... really am apprehensive about opening up K3 again ... but I know I'm just being neurotic ... will face any weekend now).
>
>The P3 was pretty much performing as expected ... given that I haven't done the above mode yet, and I live in manhattan with a mediocre hamstick hung outside my window .. I could generally see strongest stations above a lot of noise on P3. That was good.
>
>But over past few days, it seems that the sensitivity of the device was diminishing .. started to have trouble seeing the few stations that I could actually hear above the noise on my K3 ... and then today, it now appears that the P3 is basically deaf to the K3 ... I see some low ampitude noise, which doesn't vary in appearance with or without the coax cable to the IF OUT of the K3 plugged in. I am listening to a fairly strong Italian CW station now on 20 meters now, sticking his head above the omnipresent S5-6 noise ... armchair copy, if you will, but all I see is noise at the bottom of the P3 screen. The center frequency tracks my K3 nicely ... but no matter how I adjust the REF, SCALE and SPAN, all I see is noise.
>
>Any thoughts would be welcome. Yes, I will dive in and do the IF OUT mod, but am trying to understand the curious behavior, and to see if it sounds familiar to anyone.
>
>Thanks in advance
>
>-- WB2SSB
>
>Joseph J. Sanger, M.D.
>Associate Professor of Radiology
>Director, Radiology Informatics
>
>------------------------------------------------------------
>This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this 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

Bob Cunnings NW8L

Re: P3 Misbehaving?

In reply to this post by wb2ssb

Is the noise floor on the P3 stuck at -140 dBm or so all the time, no
matter what? I experienced a similar problem after 2 weeks of use,
and replacement of the P3 RF board was required. Apparently, I was
informed, another cause can be handling damage to transformers T100 or
T101 on the P3 Front Panel board, so you might take a look at them. I
sure wish the P3 schematic was available at the time, it would have
made troubleshooting a little easier (it's still not published
AFAICS). As usual, Elecraft support was prompt and efficient, I'd
contact them if there's no change.

Bob NW8L

On Sat, Sep 11, 2010 at 4:34 PM, Sanger, Joseph <[hidden email]> wrote:

Alan Bloom

Re: P3 Misbehaving?

In reply to this post by wb2ssb

> and then today, it now appears that the P3 is basically deaf to the K3 ...
> I see some low ampitude noise, which doesn't vary in appearance with or
> without the coax cable to the IF OUT of the K3 plugged in.

OM,

On a K3 with the IF OUT modification, you should definitely see the
noise level on the P3 go down when you disconnect the coax that goes
from the K3 IF OUT to the P3 IF IN. I don't have a K3 without the mod
to test with, but I'm pretty sure that, even in that case, if you turn
on the K3's preamp you should still see a change in noise level when you
disconnect the coax. If not, there is something wrong.

First check the coax cable to be sure it is properly seated at both the
K3 and P3 end. If you have another BNC coax cable available you might
try it to see if the problem is a bad cable.

You could also pop the top off the P3 and check the small coax cable
that goes from the rear-panel amplifier board to the Front Panel board.
Push with a twisting motion on the connector on each end to be sure it
is well-seated in the receptacle. (On the amplifier board, support the
board with your fingers while you do this to avoid flexing the board.)

If none of that helps I would contact Elecraft customer support and get
their recommendations on the next step.

Alan N1AL

On Sat, 2010-09-11 at 18:34 -0400, Sanger, Joseph wrote:

> Just assembled P3 a few days ago. Having a problem that I can't seem to solve.
>
> Background: Haven't done K3 OUT mod yet (SN 113 ---- fairly old) ... really am apprehensive about opening up K3 again ... but I know I'm just being neurotic ... will face any weekend now).
>
> The P3 was pretty much performing as expected ... given that I haven't done the above mode yet, and I live in manhattan with a mediocre hamstick hung outside my window .. I could generally see strongest stations above a lot of noise on P3. That was good.
>
> But over past few days, it seems that the sensitivity of the device was diminishing .. started to have trouble seeing the few stations that I could actually hear above the noise on my K3 ... and then today, it now appears that the P3 is basically deaf to the K3 ... I see some low ampitude noise, which doesn't vary in appearance with or without the coax cable to the IF OUT of the K3 plugged in. I am listening to a fairly strong Italian CW station now on 20 meters now, sticking his head above the omnipresent S5-6 noise ... armchair copy, if you will, but all I see is noise at the bottom of the P3 screen. The center frequency tracks my K3 nicely ... but no matter how I adjust the REF, SCALE and SPAN, all I see is noise.
>
> Any thoughts would be welcome. Yes, I will dive in and do the IF OUT mod, but am trying to understand the curious behavior, and to see if it sounds familiar to anyone.
>
> Thanks in advance
>
> -- WB2SSB
>
> Joseph J. Sanger, M.D.
> Associate Professor of Radiology
> Director, Radiology Informatics
>
> ------------------------------------------------------------
> This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this 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

wb2ssb

Re: P3 Misbehaving?

In reply to this post by Bob Cunnings NW8L

The noise floor shifts by 10 db each time I make a change to the PRE or ATT switch ... resulting in 3 separate noise floor levels. But you are right, the RF board turned out to be the problem! You will see on my next post, the final chapter.

Thanks very much, Bob.

-----Original Message-----
From: Bob Cunnings [mailto:[hidden email]]
Sent: Saturday, September 11, 2010 8:10 PM
To: Sanger, Joseph
Cc: [hidden email]
Subject: Re: [Elecraft] P3 Misbehaving?

Is the noise floor on the P3 stuck at -140 dBm or so all the time, no
matter what? I experienced a similar problem after 2 weeks of use,
and replacement of the P3 RF board was required. Apparently, I was
informed, another cause can be handling damage to transformers T100 or
T101 on the P3 Front Panel board, so you might take a look at them. I
sure wish the P3 schematic was available at the time, it would have
made troubleshooting a little easier (it's still not published
AFAICS). As usual, Elecraft support was prompt and efficient, I'd
contact them if there's no change.

Bob NW8L

On Sat, Sep 11, 2010 at 4:34 PM, Sanger, Joseph <[hidden email]> wrote:

------------------------------------------------------------
This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this email.
=================================

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

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Please help support this email list: http://www.qsl.net/donate.html

wb2ssb

Re: P3 Misbehaving?

In reply to this post by Matt Zilmer

Matt, you are right ... I thought the K3 was dead ... but part of the problem is band conditions ... thanks for the comment.

-----Original Message-----
From: Matt Zilmer [mailto:[hidden email]]
Sent: Saturday, September 11, 2010 7:40 PM
To: Sanger, Joseph
Cc: [hidden email]
Subject: Re: [Elecraft] P3 Misbehaving?

Idea: Change in propagation causes different band noise levels. Same
with geomagnetic activity, number of neighbors in the building, you
name it.

matt W6NIA
K3 #24
P3 #14

On Sat, 11 Sep 2010 18:34:26 -0400, you wrote:

wb2ssb

Re: P3 Misbehaving?

In reply to this post by Alan Bloom

Well, I am happy / embarrassed to say, problem solved. Alan, your troubleshooting tips led me to the solution. I am closing the loop on this, in spite of my embarrassment, in order to possibly save someone else this problem.

The problem was simply carelessness on my part. I had installed the RF board upside down ... guess what, it physically fits either right side up or upside down .. the only apparent difference visually, from the back at least, is that the little dual-position switch ... doesn't poke out of the back slot when you install board upside down. D'oh!

Flipping it right-side up solved my problem. What is odd is that it ever _sort_ of worked in the upside/down position.

Well, thanks to all who offered comments ... I REALLY appreciate it.

-- Joe
-- WB2SSB

-----Original Message-----
From: Alan Bloom [mailto:[hidden email]]
Sent: Saturday, September 11, 2010 9:04 PM
To: Sanger, Joseph
Cc: [hidden email]
Subject: Re: [Elecraft] P3 Misbehaving?

> and then today, it now appears that the P3 is basically deaf to the K3 ...
> I see some low ampitude noise, which doesn't vary in appearance with or
> without the coax cable to the IF OUT of the K3 plugged in.

OM,

On a K3 with the IF OUT modification, you should definitely see the
noise level on the P3 go down when you disconnect the coax that goes
from the K3 IF OUT to the P3 IF IN. I don't have a K3 without the mod
to test with, but I'm pretty sure that, even in that case, if you turn
on the K3's preamp you should still see a change in noise level when you
disconnect the coax. If not, there is something wrong.

First check the coax cable to be sure it is properly seated at both the
K3 and P3 end. If you have another BNC coax cable available you might
try it to see if the problem is a bad cable.

You could also pop the top off the P3 and check the small coax cable
that goes from the rear-panel amplifier board to the Front Panel board.
Push with a twisting motion on the connector on each end to be sure it
is well-seated in the receptacle. (On the amplifier board, support the
board with your fingers while you do this to avoid flexing the board.)

If none of that helps I would contact Elecraft customer support and get
their recommendations on the next step.

Alan N1AL

On Sat, 2010-09-11 at 18:34 -0400, Sanger, Joseph wrote:

> Just assembled P3 a few days ago. Having a problem that I can't seem to solve.
>
> Background: Haven't done K3 OUT mod yet (SN 113 ---- fairly old) ... really am apprehensive about opening up K3 again ... but I know I'm just being neurotic ... will face any weekend now).
>
> The P3 was pretty much performing as expected ... given that I haven't done the above mode yet, and I live in manhattan with a mediocre hamstick hung outside my window .. I could generally see strongest stations above a lot of noise on P3. That was good.
>
> But over past few days, it seems that the sensitivity of the device was diminishing .. started to have trouble seeing the few stations that I could actually hear above the noise on my K3 ... and then today, it now appears that the P3 is basically deaf to the K3 ... I see some low ampitude noise, which doesn't vary in appearance with or without the coax cable to the IF OUT of the K3 plugged in. I am listening to a fairly strong Italian CW station now on 20 meters now, sticking his head above the omnipresent S5-6 noise ... armchair copy, if you will, but all I see is noise at the bottom of the P3 screen. The center frequency tracks my K3 nicely ... but no matter how I adjust the REF, SCALE and SPAN, all I see is noise.
>
> Any thoughts would be welcome. Yes, I will dive in and do the IF OUT mod, but am trying to understand the curious behavior, and to see if it sounds familiar to anyone.
>
> Thanks in advance
>
> -- WB2SSB
>
> Joseph J. Sanger, M.D.
> Associate Professor of Radiology
> Director, Radiology Informatics
>
> ------------------------------------------------------------
> This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this 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

alorona

Re: P3 Misbehaving?

In reply to this post by Alan Bloom

Alan's advice is pertinent because I found my P3's BNC-to-BNC coax cable to be
open... swapping it with a known good one laying in my cable drawer solved that
problem. Just a warning for anybody else to go ahead and suspect the cable (as
well as everything else) if you don't see what you expect to see on the P3.

Al W6LX

________________________________________________________
OM,

First check the coax cable to be sure it is properly seated at both the
K3 and P3 end. If you have another BNC coax cable available you might
try it to see if the problem is a bad cable.

Alan N1AL
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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ab2tc

Re: [K3] Passband tuning quirk

In reply to this post by Guy, K2AV

Hi,

I will try that beta when the contest is over. Of course this minor quirk is not affecting my operation at all. Wonder why Nabble has linked this thread with another with a totally different subject.

I am pouncing on 15 at the moment. The band is virtually dead here but every so often a signal pops up on the panadapter which I have set very wide. Without it I would never have bothered with this band under these conditions.

AB2TC - Knut

Guy, K2AV wrote

I have beta firmware 4.10 and I just went through your procedure
below. Mine tracks correctly. I get the correct numbers. I seem to
recall some text about what you report some while back, so it seems it
has had some attention paid to it. Does not sound like it's keeping
you from hearing anything or adjusting it. But you can try the beta
version:

ftp://ftp.elecraft.com/K3/firmware/beta/k3fw4r10.zip

73, Guy.

ab2tc

Re: [K3] Passband tuning quirk

Well, the contest is over and I loaded the 4.10 beta. It did not fix the problem. I have made the discovery that this is only a problem on USB. Finished the contest on 40m LSB and found that it was not a problem there. Made some more tests and found that the problem follows the USB mode regardless of band. It turns out it's not completely without consequences for my operation as it prevents the switch to my 1.8kHz filter when selecting the 0.3-2.1kHz bandwidth which is pretty well the smallest BW I ever use. So a fix would be welcome. I do not think this is something that is introduced with recent firmware changes. Rather I think this has been latent for a long time and has cropped up with something that I have done to my settings. BTW on USB now the indicated BW is always 50Hz higher than it ought to be for all settings. Is there some secret memory dump I can do to shed some light on the problem?

AB2TC - Knut

<quote author="ab2tc">
Hi,

I will try that beta when the contest is over. Of course this minor quirk is not affecting my operation at all. Wonder why Nabble has linked this thread with another with a totally different subject.

I am pouncing on 15 at the moment. The band is virtually dead here but every so often a signal pops up on the panadapter which I have set very wide. Without it I would never have bothered with this band under these conditions.

AB2TC - Knut
<snip

</quote>

ab2tc

Re: [K3] Passband tuning quirk

Hi,

I'll be darned. Today the problem is gone and the 1.8kHz filter kicks in when it should. I did receive an E-mail asking if I cycled power after upgrading the firmware. It is my habit to do so but not absolutely sure if I did or not.

AB2TC - Knut

ab2tc wrote

Well, the contest is over and I loaded the 4.10 beta. It did not fix the problem.
<snip>

Guy, K2AV

Re: [K3] Passband tuning quirk

Yup, I asked you that.... :>) Of course, ME, I've NEVER done
that.....<grin>.

Most of the time on this one it's the flashlight that fixes it. I
would say that really always needs to be a K3-utility shut down + 30
second off K3 power off. It's the same as the reboot after Windows
upgrades that change things that were in use. No matter how much
stuff can be force-booted while running, nobody can do that for
everything and shutdown is required.

All's well that ends well. Onward and upward...

73, Guy

On Mon, Sep 13, 2010 at 2:16 PM, ab2tc <[hidden email]> wrote:

>
> Hi,
>
> I'll be darned. Today the problem is gone and the 1.8kHz filter kicks in
> when it should. I did receive an E-mail asking if I cycled power after
> upgrading the firmware. It is my habit to do so but not absolutely sure if I
> did or not.
>
> AB2TC - Knut
>
>
> ab2tc wrote:
>>
>> Well, the contest is over and I loaded the 4.10 beta. It did not fix the
>> problem.
>> <snip>
>>
>
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/K3-Passband-tuning-quirk-tp5522141p5527395.html
> Sent from the [K3] mailing list archive at Nabble.com.
> ______________________________________________________________
> 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
>