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K3 deaf when narrow filter engaged

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Andrew Moore-3

K3 deaf when narrow filter engaged

New K3 with 3 filters:

FL1 - empty
FL2 - 2700 Hz
FL3 - empty
FL4 - 400 Hz
FL5 - 200 Hz

FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged into
right slots (FL1 can remain empty right?)

When I turn the bandwidth encoder CCW, everything's fine until I hit 400 Hz.
At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet from
then on.

Ideas?

Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV signal. The
K3 hears it at about S5 max, not even close to S9. Followed the calibration
instructions.

--Andrew, NV1B
..
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Guy, K2AV

Re: K3 deaf when narrow filter engaged

The most likely cause of your problem is that the filter placements as
viewed in the K3 utility and as actually installed on the main board
do not actually match. Next is that you have left an empty slot
ENABLED in the K3 utility. After that, a filter not plugged all the
way in or defective.

73, Guy.

On Fri, Jul 8, 2011 at 8:06 PM, Andrew Moore <[hidden email]> wrote:

> New K3 with 3 filters:
>
> FL1 - empty
> FL2 - 2700 Hz
> FL3 - empty
> FL4 - 400 Hz
> FL5 - 200 Hz
>
> FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged into
> right slots (FL1 can remain empty right?)
>
> When I turn the bandwidth encoder CCW, everything's fine until I hit 400 Hz.
> At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet from
> then on.
>
> Ideas?
>
> Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV signal. The
> K3 hears it at about S5 max, not even close to S9. Followed the calibration
> instructions.
>
> --Andrew, NV1B
> ..
> ______________________________________________________________
> 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]

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Andrew Moore-3

Re: K3 deaf when narrow filter engaged

Filter placements are correct, and no empty slots are enabled -- I've done
the setup both ways: manually via CONFIG on the K3 itself, and via the K3
utility. Done it many times now.

Here's the odd part:

If I change the frequency offsets in the K3 (via CONFIG menu), I can dial
across the range of value offsets and peak a signal almost to the point at
which things sound like they're operating properly. Same thing happens for
3 of my filters -- the 2.7k, 400 Hz and 200 Hz. In all cases the specified
offset is not the one value that gives the strongest signal. Using the
specified offsets, it seems like the signal is not properly centered in the
passband.

What are the chances all three of my filters have the wrong offsets?
Possible but doubtful.

Is there some other setting on the K3 that I may have inadvertently tweaked
during calibration that would have thrown off all filters?

I'm stumped.

--Andrew, NV1B
..

On Fri, Jul 8, 2011 at 9:35 PM, Guy Olinger K2AV <[hidden email]>wrote:

> The most likely cause of your problem is that the filter placements as
> viewed in the K3 utility and as actually installed on the main board
> do not actually match. Next is that you have left an empty slot
> ENABLED in the K3 utility. After that, a filter not plugged all the
> way in or defective.
>
> 73, Guy.
>
> On Fri, Jul 8, 2011 at 8:06 PM, Andrew Moore <[hidden email]>
> wrote:
> > New K3 with 3 filters:
> >
> > FL1 - empty
> > FL2 - 2700 Hz
> > FL3 - empty
> > FL4 - 400 Hz
> > FL5 - 200 Hz
> >
> > FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged into
> > right slots (FL1 can remain empty right?)
> >
> > When I turn the bandwidth encoder CCW, everything's fine until I hit 400
> Hz.
> > At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet
> from
> > then on.
> >
> > Ideas?
> >
> > Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV signal.
> The
> > K3 hears it at about S5 max, not even close to S9. Followed the
> calibration
> > instructions.
> >
> > --Andrew, NV1B
> > ..
> > ______________________________________________________________
> > 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
> >
>

Matt Zilmer

Re: K3 deaf when narrow filter engaged

The chances of that are negligible. You should send your original
email and all follow-ups to [hidden email].

I have heard of a lot of strange K3 symptoms, but this one is beyond
the pale. It sounds like one of the pre- or post-roofing filter
components is somehow shifting the resonance, and looking at the
schematic I just don't see how that's possible unless there is a
bypass-value in place of a regular cap. Conventional SMT assembly -
that would not happen.

I'm no expert, but this probably is not some trouble that can be shot
over email. One of the Elecraft gang can help you narrow it down, but
it should probably be done interactively over the phone or Skype or
whatever.

You *may* be able to avoid the additional hassle by running the EE
INIT procedure on your K3 and starting over. This will only work if
there isn't some defect in the hardware, but that is so unlikely that
running EE INIT is your best bet. See p66 of the Owner's Manual (rev
D7), or use Adobe to search for "Parameter Initialization". If you
dorked a setting, then EE INIT will solve that problem and put your K3
into its factory default settings.

Good Luck. No matter what you can or can't get done in short order,
Elecraft will assist you with any problem.

73,

matt W6NIA
K3 #24

==

On Fri, 08 Jul 2011 23:40:40 -0400, you wrote:

>Filter placements are correct, and no empty slots are enabled -- I've done
>the setup both ways: manually via CONFIG on the K3 itself, and via the K3
>utility. Done it many times now.
>
>Here's the odd part:
>
>If I change the frequency offsets in the K3 (via CONFIG menu), I can dial
>across the range of value offsets and peak a signal almost to the point at
>which things sound like they're operating properly. Same thing happens for
>3 of my filters -- the 2.7k, 400 Hz and 200 Hz. In all cases the specified
>offset is not the one value that gives the strongest signal. Using the
>specified offsets, it seems like the signal is not properly centered in the
>passband.
>
>What are the chances all three of my filters have the wrong offsets?
> Possible but doubtful.
>
>Is there some other setting on the K3 that I may have inadvertently tweaked
>during calibration that would have thrown off all filters?
>
>I'm stumped.
>
>--Andrew, NV1B
>..
>
>
>
>
>
>On Fri, Jul 8, 2011 at 9:35 PM, Guy Olinger K2AV <[hidden email]>wrote:
>
>> The most likely cause of your problem is that the filter placements as
>> viewed in the K3 utility and as actually installed on the main board
>> do not actually match. Next is that you have left an empty slot
>> ENABLED in the K3 utility. After that, a filter not plugged all the
>> way in or defective.
>>
>> 73, Guy.
>>
>> On Fri, Jul 8, 2011 at 8:06 PM, Andrew Moore <[hidden email]>
>> wrote:
>> > New K3 with 3 filters:
>> >
>> > FL1 - empty
>> > FL2 - 2700 Hz
>> > FL3 - empty
>> > FL4 - 400 Hz
>> > FL5 - 200 Hz
>> >
>> > FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged into
>> > right slots (FL1 can remain empty right?)
>> >
>> > When I turn the bandwidth encoder CCW, everything's fine until I hit 400
>> Hz.
>> > At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet
>> from
>> > then on.
>> >
>> > Ideas?
>> >
>> > Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV signal.
>> The
>> > K3 hears it at about S5 max, not even close to S9. Followed the
>> calibration
>> > instructions.
>> >
>> > --Andrew, NV1B
>> > ..
>> > ______________________________________________________________
>> > 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

Andrew Moore-3

Re: K3 deaf when narrow filter engaged

Problem solved -- I think....

I ended up doing a factory reset (power-up while pressing/holding Shift knob
in until power up completed), EE INIT. And I just read through the rest of
your note and now see that's what you suggested!

I then went through the entire setup process.

What I did differently this time was during the reference oscillator
calibration, I found that much less of an adjustment was needed than what I
did before. In fact it was fine as-is. I'm not sure what prompted me to
adjust the oscillator before (I used WWV as an on-air reference), but this
time around, everything came out fine.

I suspect my incorrect reference oscillator adjustment explains why all
three filters appeared to have incorrect offsets.

Now the only remaining problem is getting the rig to show S9 with a 50 uV
source. The adjustment range doesn't go far enough to produce S9 on the
display. I put a new battery in the XG2 signal source, same problem. I'm
not too concerned about this one -- only mildly annoyed. This is a very
minor problem compared to what I *thought* was wrong with my filters!

Thanks for your detailed response -- appreciated.

--Andrew, NV1B

On Sat, Jul 9, 2011 at 12:33 AM, Matt Zilmer <[hidden email]> wrote:

> The chances of that are negligible. You should send your original
> email and all follow-ups to [hidden email].
>
> I have heard of a lot of strange K3 symptoms, but this one is beyond
> the pale. It sounds like one of the pre- or post-roofing filter
> components is somehow shifting the resonance, and looking at the
> schematic I just don't see how that's possible unless there is a
> bypass-value in place of a regular cap. Conventional SMT assembly -
> that would not happen.
>
> I'm no expert, but this probably is not some trouble that can be shot
> over email. One of the Elecraft gang can help you narrow it down, but
> it should probably be done interactively over the phone or Skype or
> whatever.
>
> You *may* be able to avoid the additional hassle by running the EE
> INIT procedure on your K3 and starting over. This will only work if
> there isn't some defect in the hardware, but that is so unlikely that
> running EE INIT is your best bet. See p66 of the Owner's Manual (rev
> D7), or use Adobe to search for "Parameter Initialization". If you
> dorked a setting, then EE INIT will solve that problem and put your K3
> into its factory default settings.
>
> Good Luck. No matter what you can or can't get done in short order,
> Elecraft will assist you with any problem.
>
> 73,
>
> matt W6NIA
> K3 #24
>
> ==
>
>
> On Fri, 08 Jul 2011 23:40:40 -0400, you wrote:
>
> >Filter placements are correct, and no empty slots are enabled -- I've done
> >the setup both ways: manually via CONFIG on the K3 itself, and via the K3
> >utility. Done it many times now.
> >
> >Here's the odd part:
> >
> >If I change the frequency offsets in the K3 (via CONFIG menu), I can dial
> >across the range of value offsets and peak a signal almost to the point at
> >which things sound like they're operating properly. Same thing happens
> for
> >3 of my filters -- the 2.7k, 400 Hz and 200 Hz. In all cases the
> specified
> >offset is not the one value that gives the strongest signal. Using the
> >specified offsets, it seems like the signal is not properly centered in
> the
> >passband.
> >
> >What are the chances all three of my filters have the wrong offsets?
> > Possible but doubtful.
> >
> >Is there some other setting on the K3 that I may have inadvertently
> tweaked
> >during calibration that would have thrown off all filters?
> >
> >I'm stumped.
> >
> >--Andrew, NV1B
> >..
> >
> >
> >
> >
> >
> >On Fri, Jul 8, 2011 at 9:35 PM, Guy Olinger K2AV <[hidden email]
> >wrote:
> >
> >> The most likely cause of your problem is that the filter placements as
> >> viewed in the K3 utility and as actually installed on the main board
> >> do not actually match. Next is that you have left an empty slot
> >> ENABLED in the K3 utility. After that, a filter not plugged all the
> >> way in or defective.
> >>
> >> 73, Guy.
> >>
> >> On Fri, Jul 8, 2011 at 8:06 PM, Andrew Moore <[hidden email]>
> >> wrote:
> >> > New K3 with 3 filters:
> >> >
> >> > FL1 - empty
> >> > FL2 - 2700 Hz
> >> > FL3 - empty
> >> > FL4 - 400 Hz
> >> > FL5 - 200 Hz
> >> >
> >> > FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged
> into
> >> > right slots (FL1 can remain empty right?)
> >> >
> >> > When I turn the bandwidth encoder CCW, everything's fine until I hit
> 400
> >> Hz.
> >> > At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet
> >> from
> >> > then on.
> >> >
> >> > Ideas?
> >> >
> >> > Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV
> signal.
> >> The
> >> > K3 hears it at about S5 max, not even close to S9. Followed the
> >> calibration
> >> > instructions.
> >> >
> >> > --Andrew, NV1B
> >> > ..
> >> > ______________________________________________________________
> >> > 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
>

Matt Zilmer

Re: K3 deaf when narrow filter engaged

EE INIT solves problems if the factory init didn't take. I've only
heard of that once (my K3, one of the first kits). Elecraft has the
assembly and factory handling procedures down to a hard-coded science
by now, so it should not happen at all.

Having the ref osc off by a whole bunch, for example 1 KHz, would
definitely give weird results. Normally the ref osc calibration is
pretty close - 5 to 6Hz at the outside - from what I know of it. I've
helped a few kit builders go through the paces and never seen cal
errors start out that high.

The gain and S-meter calibrations should go smoothly now that you're
past the important "radio really works" setup.

Enjoy your first K3 weekend! I still remember mine - CQ WW SSB using
my first K3 incarnation - a K3/10. Seven new countries under really
un-stellar conditions....

You're welcome.

73,
matt W6NIA

On Sat, 09 Jul 2011 00:44:33 -0400, you wrote:

>Problem solved -- I think....
>
>I ended up doing a factory reset (power-up while pressing/holding Shift knob
>in until power up completed), EE INIT. And I just read through the rest of
>your note and now see that's what you suggested!
>
>I then went through the entire setup process.
>
>What I did differently this time was during the reference oscillator
>calibration, I found that much less of an adjustment was needed than what I
>did before. In fact it was fine as-is. I'm not sure what prompted me to
>adjust the oscillator before (I used WWV as an on-air reference), but this
>time around, everything came out fine.
>
>I suspect my incorrect reference oscillator adjustment explains why all
>three filters appeared to have incorrect offsets.
>
>Now the only remaining problem is getting the rig to show S9 with a 50 uV
>source. The adjustment range doesn't go far enough to produce S9 on the
>display. I put a new battery in the XG2 signal source, same problem. I'm
>not too concerned about this one -- only mildly annoyed. This is a very
>minor problem compared to what I *thought* was wrong with my filters!
>
>Thanks for your detailed response -- appreciated.
>
>--Andrew, NV1B
>
>
>
>On Sat, Jul 9, 2011 at 12:33 AM, Matt Zilmer <[hidden email]> wrote:
>
>> The chances of that are negligible. You should send your original
>> email and all follow-ups to [hidden email].
>>
>> I have heard of a lot of strange K3 symptoms, but this one is beyond
>> the pale. It sounds like one of the pre- or post-roofing filter
>> components is somehow shifting the resonance, and looking at the
>> schematic I just don't see how that's possible unless there is a
>> bypass-value in place of a regular cap. Conventional SMT assembly -
>> that would not happen.
>>
>> I'm no expert, but this probably is not some trouble that can be shot
>> over email. One of the Elecraft gang can help you narrow it down, but
>> it should probably be done interactively over the phone or Skype or
>> whatever.
>>
>> You *may* be able to avoid the additional hassle by running the EE
>> INIT procedure on your K3 and starting over. This will only work if
>> there isn't some defect in the hardware, but that is so unlikely that
>> running EE INIT is your best bet. See p66 of the Owner's Manual (rev
>> D7), or use Adobe to search for "Parameter Initialization". If you
>> dorked a setting, then EE INIT will solve that problem and put your K3
>> into its factory default settings.
>>
>> Good Luck. No matter what you can or can't get done in short order,
>> Elecraft will assist you with any problem.
>>
>> 73,
>>
>> matt W6NIA
>> K3 #24
>>
>> ==
>>
>>
>> On Fri, 08 Jul 2011 23:40:40 -0400, you wrote:
>>
>> >Filter placements are correct, and no empty slots are enabled -- I've done
>> >the setup both ways: manually via CONFIG on the K3 itself, and via the K3
>> >utility. Done it many times now.
>> >
>> >Here's the odd part:
>> >
>> >If I change the frequency offsets in the K3 (via CONFIG menu), I can dial
>> >across the range of value offsets and peak a signal almost to the point at
>> >which things sound like they're operating properly. Same thing happens
>> for
>> >3 of my filters -- the 2.7k, 400 Hz and 200 Hz. In all cases the
>> specified
>> >offset is not the one value that gives the strongest signal. Using the
>> >specified offsets, it seems like the signal is not properly centered in
>> the
>> >passband.
>> >
>> >What are the chances all three of my filters have the wrong offsets?
>> > Possible but doubtful.
>> >
>> >Is there some other setting on the K3 that I may have inadvertently
>> tweaked
>> >during calibration that would have thrown off all filters?
>> >
>> >I'm stumped.
>> >
>> >--Andrew, NV1B
>> >..
>> >
>> >
>> >
>> >
>> >
>> >On Fri, Jul 8, 2011 at 9:35 PM, Guy Olinger K2AV <[hidden email]
>> >wrote:
>> >
>> >> The most likely cause of your problem is that the filter placements as
>> >> viewed in the K3 utility and as actually installed on the main board
>> >> do not actually match. Next is that you have left an empty slot
>> >> ENABLED in the K3 utility. After that, a filter not plugged all the
>> >> way in or defective.
>> >>
>> >> 73, Guy.
>> >>
>> >> On Fri, Jul 8, 2011 at 8:06 PM, Andrew Moore <[hidden email]>
>> >> wrote:
>> >> > New K3 with 3 filters:
>> >> >
>> >> > FL1 - empty
>> >> > FL2 - 2700 Hz
>> >> > FL3 - empty
>> >> > FL4 - 400 Hz
>> >> > FL5 - 200 Hz
>> >> >
>> >> > FL2,4,5 enabled, offsets and bandwidths entered, and filters plugged
>> into
>> >> > right slots (FL1 can remain empty right?)
>> >> >
>> >> > When I turn the bandwidth encoder CCW, everything's fine until I hit
>> 400
>> >> Hz.
>> >> > At 450, I hear signal. At 400, when FL4 kicks in, receiver goes quiet
>> >> from
>> >> > then on.
>> >> >
>> >> > Ideas?
>> >> >
>> >> > Also - RF calibration - I'm using an XG2 to feed the K3 a 50 uV
>> signal.
>> >> The
>> >> > K3 hears it at about S5 max, not even close to S9. Followed the
>> >> calibration
>> >> > instructions.
>> >> >
>> >> > --Andrew, NV1B
>> >> > ..
>> >> > ______________________________________________________________
>> >> > 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
>>

Bill W4ZV

Re: K3 deaf when narrow filter engaged

In reply to this post by Andrew Moore-3

Andrew Moore-3 wrote

Now the only remaining problem is getting the rig to show S9 with a 50 uV
source. The adjustment range doesn't go far enough to produce S9 on the
display. I put a new battery in the XG2 signal source, same problem.

1. Did you first do the RF Gain Calibration using the K3 Utility?
2. Are you zero beat on the signal? You can use CWT if you're not able to zero beat by ear.

73, Bill

Andrew Moore-3

Re: K3 deaf when narrow filter engaged

Hi Bill - yes, RF Gain Calibration done first, and always zero beat. I was
trying to set it up with S-meter mode Absolute, not Relative, since I am
using an XG2. I ended up going back to relative and things are behaving
normally, but I'd love to get this Absolute mode working. Maybe my XG2 isn't
doing 50 uV properly.

Thanks,
--Andrew, NV1B
..

W4ZV> 1. Did you first do the RF Gain Calibration using the K3 Utility?
W4ZV> 2. Are you zero beat on the signal?

NV1B>> Now the only remaining problem is getting the rig to show S9 with a
50 uV source.
______________________________________________________________
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

Bill W4ZV

Re: K3 deaf when narrow filter engaged

I'm sure you know this but in ABS mode, be sure to turn both PREamp and
ATTenuator off. And be sure to start with SMTR SC = 14 before adjusting
SMTR OF for S9 (adjust so it just turns to S9 coming from S8). All of this
is in the manual but I'm just hoping you overlooked a step.

I doubt it's your XG2 but you never know! I have the XG3 and my old XG1 is
within ~2 dB of it at 50 uV. Using the latest RF Cal routine with the XG3's
-33 dBm output you can adjust the K3 so it reads perfectly at all levels in
ABS mode.

73 & GL!

Bill

On Sat, Jul 9, 2011 at 8:26 AM, Andrew Moore <[hidden email]> wrote:

Hi Bill - yes, RF Gain Calibration done first, and always zero beat. I was

> trying to set it up with S-meter mode Absolute, not Relative, since I am
> using an XG2. I ended up going back to relative and things are behaving
> normally, but I'd love to get this Absolute mode working. Maybe my XG2 isn't
> doing 50 uV properly.
>
> Thanks,
> --Andrew, NV1B
> ..
>
> W4ZV> 1. Did you first do the RF Gain Calibration using the K3 Utility?
> W4ZV> 2. Are you zero beat on the signal?
>
> NV1B>> Now the only remaining problem is getting the rig to show S9 with a
> 50 uV source.
>
>