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KX3 Filter Blow-By

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Jimk8mr

KX3 Filter Blow-By

A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
from loud CW stations. I can hear such stations up to several KHz away. I
suspect the range is limited by the audio response of the system, including
my ears. Both sides of zero beat, though less so on the opposite side of
the zero beat.

In the CA QSO Party this weekend, maybe the loudest 10% of the stations on
10 CW Saturday afternoon were leaking through. (I've heard the leakage on
other bands as well.)

I don't have any roofing filters. (I figured any stations weak enough for
me to need the filter to hear, would never be able to hear me anyway).

Is this normal, or is there some shielding or other issue affecting my
unit? (It is a kit version).

73 - Jim K8MR
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mzilmer

Re: KX3 Filter Blow-By

At 10% of all CW on 10m, it's probably a combination of splatter and frequency proximity. The roofing filter will only help with the latter problem

Matt Zilmer, W6NIA

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of [hidden email]
Sent: Monday, October 08, 2012 10:46 AM
To: [hidden email]
Subject: [Elecraft] KX3 Filter Blow-By

A recent KX3 owner (# 1677), I've noticed hearing out of passband signals from loud CW stations. I can hear such stations up to several KHz away. I suspect the range is limited by the audio response of the system, including my ears. Both sides of zero beat, though less so on the opposite side of the zero beat.

In the CA QSO Party this weekend, maybe the loudest 10% of the stations on
10 CW Saturday afternoon were leaking through. (I've heard the leakage on other bands as well.)

I don't have any roofing filters. (I figured any stations weak enough for me to need the filter to hear, would never be able to hear me anyway).

Is this normal, or is there some shielding or other issue affecting my unit? (It is a kit version).

73 - Jim K8MR
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Oliver Dröse

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

Hi Jim,

did you have VFO NR enabled by chance? I suppose yes, as the KX3 is quite
unusable on the high bands without. :-( There is a known issue = bad effect
of the DSP leading to "artifacts", i.e. hearing signals +/- 5-6 kHz again
from strong stations. If you turn off VFO NR it goes away, but then the VFO
noise is much too strong. :-( Another bad effect is even with VFO NR enabled
if you tune "over" strong stations you suddenly have strong VFO noise until
you stop turning the wheel. Afterwards it's gone again. And if you turn the
VFO fast enough you will not even recognize even 59+ signals. :-( All
problems from the VFO NR DSP implementation as confirmed by Elecraft. And no
matter if with or without roofing filter and with/without 8 kHz shift
enabled. Still wonder why nobody else is complaining about those effects?
Cannot be that everybody has an s4 noise level on 12, 10 & 6 m that would
mask the VFO noise and thus no need to enable VFO NR.

I documented all those effects on video and sent it over to Wayne. He said
he and Lyle are working on it, hopefully with some results soon, otherwise
the KX3 is of no use for a high band op like me. :-( Never seen such
problems with *any* other rig owned so far ...

73, Olli - DH8BQA

----- Original Message -----
From: <[hidden email]>
To: <[hidden email]>
Sent: Monday, October 08, 2012 7:46 PM
Subject: [Elecraft] KX3 Filter Blow-By

>A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
> from loud CW stations. I can hear such stations up to several KHz away. I
> suspect the range is limited by the audio response of the system,
> including
> my ears. Both sides of zero beat, though less so on the opposite side of
> the zero beat.
>
> In the CA QSO Party this weekend, maybe the loudest 10% of the stations on
> 10 CW Saturday afternoon were leaking through. (I've heard the leakage on
> other bands as well.)
>
> I don't have any roofing filters. (I figured any stations weak enough for
> me to need the filter to hear, would never be able to hear me anyway).
>
> Is this normal, or is there some shielding or other issue affecting my
> unit? (It is a kit version).
>
>
> 73 - Jim K8MR
> ______________________________________________________________
> 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
>
>
> -----
> E-Mail ist virenfrei.
> Von AVG uberpruft - www.avg.de
> Version: 2012.0.2221 / Virendatenbank: 2441/5317 - Ausgabedatum:
> 08.10.2012
>

wayne burdick

Re: KX3 Filter Blow-By

Administrator

In reply to this post by Jimk8mr

Hi Jim,

This is most likely related to opposite sideband suppression, not
filter blow-by. Nominal factory calibration results in OSB suppression
of around 55-60 dB. You can improve on this using a new procedure we
developed a month or so ago. It requires a strong signal source on
each band to be optimized. I can send you the firmware and
instructions if you're interested.

73,
Wayne
N6KR

On Oct 8, 2012, at 10:46 AM, [hidden email] wrote:

> A recent KX3 owner (# 1677), I've noticed hearing out of passband
> signals
> from loud CW stations. I can hear such stations up to several KHz
> away. I
> suspect the range is limited by the audio response of the system,
> including
> my ears. Both sides of zero beat, though less so on the opposite
> side of
> the zero beat.
>
> In the CA QSO Party this weekend, maybe the loudest 10% of the
> stations on
> 10 CW Saturday afternoon were leaking through. (I've heard the
> leakage on
> other bands as well.)
>
> I don't have any roofing filters. (I figured any stations weak
> enough for
> me to need the filter to hear, would never be able to hear me anyway).
>
> Is this normal, or is there some shielding or other issue affecting my
> unit? (It is a kit version).
>
>
> 73 - Jim K8MR
> ______________________________________________________________
> 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

David Gilbert

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

"I don't have any roofing filters. (I figured any stations weak enough
for me to need the filter to hear, would never be able to hear me anyway)."

Sorry, but I don't understand that logic. Let's say that you and I are
the only ones on the band and we're both weak but readable for each
other. A powerful third station fires up 5 kHz away from us, but the
skip is such that he is much stronger for you than he is for me. I can
still hear you fine but you can no longer hear me.

Roofing filters are your friend. They won't do a thing for splatter but
they will greatly enhance your rig.

73,
Dave AB7E

On 10/8/2012 10:46 AM, [hidden email] wrote:

M5FRA - Colin

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

Jim, can't say that I have noticed the problem you mention, in fact I
was thinking the KX3 was handling close in strong stations better than
my TS-590. I do have the roofing filters and also am tending to use
bandwidths of 100-300Hz. There are a lot more key clicks, buzzing and
general noise these days, my guess a lot is from incorrectly setup
amplifiers/rigs with bad CW waveforms or both!

Colin - G8FRA/M5FRA

m5fra.org.uk <http://www.m5fra.org.uk>

------ Original Message ------
From: [hidden email]
To: [hidden email]
Sent: 08/10/2012 18:46:09
Subject: [Elecraft] KX3 Filter Blow-By

>A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
>from loud CW stations. I can hear such stations up to several KHz away. I
>suspect the range is limited by the audio response of the system, including
>my ears. Both sides of zero beat, though less so on the opposite side of
>the zero beat.
>
>In the CA QSO Party this weekend, maybe the loudest 10% of the stations on
>10 CW Saturday afternoon were leaking through. (I've heard the leakage on
>other bands as well.)
>
>I don't have any roofing filters. (I figured any stations weak enough for
>me to need the filter to hear, would never be able to hear me anyway).
>
>Is this normal, or is there some shielding or other issue affecting my
>unit? (It is a kit version).
>
>
>73 - Jim K8MR
>______________________________________________________________
>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
>
>

Igor Sokolov-2

Re: KX3 Filter Blow-By

In reply to this post by Oliver Dröse

Olli,
Very interesting. I have experienced this effect recently when operating
from 2400 m high summit as TA4/UA9CDC. I thought the reason is opposite side
band not well suppressed. Therefore I was going to ask Wayne to send me that
beta firmware they have developed in order to rectify the issue. Now I will
have to try to see if that VFO NR is the culprit.
Here at home I have usually pretty high noise level that simply masks these
weak artifact signals. Therefore it is not an issue. But I have purchased
KX3 just to go to quiet locations and enjoy operating from there and being
able to hear what I miss from the city.
Thank you for very interesting info.

73, Igor UA9CDC
----- Original Message -----
From: "Oliver Dröse" <[hidden email]>
To: <[hidden email]>; <[hidden email]>
Sent: Tuesday, October 09, 2012 12:59 AM
Subject: Re: [Elecraft] KX3 Filter Blow-By

> Hi Jim,
>
> did you have VFO NR enabled by chance? I suppose yes, as the KX3 is quite
> unusable on the high bands without. :-( There is a known issue = bad
> effect
> of the DSP leading to "artifacts", i.e. hearing signals +/- 5-6 kHz again
> from strong stations. If you turn off VFO NR it goes away, but then the
> VFO
> noise is much too strong. :-( Another bad effect is even with VFO NR
> enabled
> if you tune "over" strong stations you suddenly have strong VFO noise
> until
> you stop turning the wheel. Afterwards it's gone again. And if you turn
> the
> VFO fast enough you will not even recognize even 59+ signals. :-( All
> problems from the VFO NR DSP implementation as confirmed by Elecraft. And
> no
> matter if with or without roofing filter and with/without 8 kHz shift
> enabled. Still wonder why nobody else is complaining about those effects?
> Cannot be that everybody has an s4 noise level on 12, 10 & 6 m that would
> mask the VFO noise and thus no need to enable VFO NR.
>
> I documented all those effects on video and sent it over to Wayne. He said
> he and Lyle are working on it, hopefully with some results soon, otherwise
> the KX3 is of no use for a high band op like me. :-( Never seen such
> problems with *any* other rig owned so far ...
>
> 73, Olli - DH8BQA
>
>
>
> ----- Original Message -----
> From: <[hidden email]>
> To: <[hidden email]>
> Sent: Monday, October 08, 2012 7:46 PM
> Subject: [Elecraft] KX3 Filter Blow-By
>
>
>>A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
>> from loud CW stations. I can hear such stations up to several KHz away.
>> I
>> suspect the range is limited by the audio response of the system,
>> including
>> my ears. Both sides of zero beat, though less so on the opposite side of
>> the zero beat.
>>
>> In the CA QSO Party this weekend, maybe the loudest 10% of the stations
>> on
>> 10 CW Saturday afternoon were leaking through. (I've heard the leakage on
>> other bands as well.)
>>
>> I don't have any roofing filters. (I figured any stations weak enough
>> for
>> me to need the filter to hear, would never be able to hear me anyway).
>>
>> Is this normal, or is there some shielding or other issue affecting my
>> unit? (It is a kit version).
>>
>>
>> 73 - Jim K8MR
>> ______________________________________________________________
>> 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
>>
>>
>> -----
>> E-Mail ist virenfrei.
>> Von AVG uberpruft - www.avg.de
>> Version: 2012.0.2221 / Virendatenbank: 2441/5317 - Ausgabedatum:
>> 08.10.2012
>>
>
> ______________________________________________________________
> 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

M5FRA - Colin

Re: KX3 Filter Blow-By

In reply to this post by M5FRA - Colin

As a update to my previous post I measured the opposite sideband
rejection on 20m and got 58db which is within spec and not that bad for
a direct conversion RX. While I would like it to be better I can live
with those sort of figures.

Colin - G8FRA/M5FRA

m5fra.org.uk <http://www.m5fra.org.uk>

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Jimk8mr

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

I did some more careful checking this morning, transmitting a few watts on
the FT-1000MP and using a couple of inches of wire as an antenna on the
KX3, on a quiet 10 meter band. The S-meter on the KX3 was 9+

There is noticeable opposite (lower frequency) side suppression issues,
but this cuts off at about 900 Hz

On the higher side, I can hear signal to as far as my hearing and/or the
audio chain permit. The most interesting note was that the undesired signal
(high side only) takes a sharp dip or disappears every 50Hz, at .00 or .05
on the frequency readout.

I'm not sure what to make of all this, but FWIW . . .

73 - Jim K8MR

In a message dated 10/8/2012 3:29:37 P.M. Eastern Daylight Time,
[hidden email] writes:

Hi Jim,

did you have VFO NR enabled by chance? I suppose yes, as the KX3 is quite
unusable on the high bands without. :-( There is a known issue = bad
effect
of the DSP leading to "artifacts", i.e. hearing signals +/- 5-6 kHz again
from strong stations. If you turn off VFO NR it goes away, but then the
VFO
noise is much too strong. :-( Another bad effect is even with VFO NR
enabled
if you tune "over" strong stations you suddenly have strong VFO noise
until
you stop turning the wheel. Afterwards it's gone again. And if you turn
the
VFO fast enough you will not even recognize even 59+ signals. :-( All
problems from the VFO NR DSP implementation as confirmed by Elecraft. And
no
matter if with or without roofing filter and with/without 8 kHz shift
enabled. Still wonder why nobody else is complaining about those effects?
Cannot be that everybody has an s4 noise level on 12, 10 & 6 m that would
mask the VFO noise and thus no need to enable VFO NR.

I documented all those effects on video and sent it over to Wayne. He said
he and Lyle are working on it, hopefully with some results soon, otherwise
the KX3 is of no use for a high band op like me. :-( Never seen such
problems with *any* other rig owned so far ...

73, Olli - DH8BQA

----- Original Message -----
From: <[hidden email]>
To: <[hidden email]>
Sent: Monday, October 08, 2012 7:46 PM
Subject: [Elecraft] KX3 Filter Blow-By

>A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
> from loud CW stations. I can hear such stations up to several KHz away.
I
> suspect the range is limited by the audio response of the system,
> including
> my ears. Both sides of zero beat, though less so on the opposite side of
> the zero beat.
>
> In the CA QSO Party this weekend, maybe the loudest 10% of the stations
on
> 10 CW Saturday afternoon were leaking through. (I've heard the leakage on
> other bands as well.)
>
> I don't have any roofing filters. (I figured any stations weak enough
for

> me to need the filter to hear, would never be able to hear me anyway).
>
> Is this normal, or is there some shielding or other issue affecting my
> unit? (It is a kit version).
>
>
> 73 - Jim K8MR
> ______________________________________________________________
> 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
>
>
> -----
> E-Mail ist virenfrei.
> Von AVG uberpruft - www.avg.de
> Version: 2012.0.2221 / Virendatenbank: 2441/5317 - Ausgabedatum:
> 08.10.2012
>

______________________________________________________________
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______________________________________________________________
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M5FRA - Colin

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

Jim, that prompted me to fire up the sig gen and have a look. On all HF
bands I found that with an S9 +30 sig the opposite sideband is around
55db down, i.e. around S3-4. With an S9 sig it is barley audible and it
takes an S9+15 (approx) for the opposite sideband to register on the S
meter. The settings were PRE (20db) = on, B/W 250Hz, XFIL=FL3. I did
not get the the 50Hz sigs that you found. Could that have been front
end overload? I use mostly CW and have not found any of this to be a
problem.

Colin - G8FRA/M5FRA

m5fra.org.uk < http://www.m5fra.org.uk>

------ Original Message ------
From: [hidden email]
To: [hidden email];[hidden email];[hidden email]
Sent: 09/10/2012 13:48:23
Subject: Re: [Elecraft] KX3 Filter Blow-By

>I did some more careful checking this morning, transmitting a few
>watts on
>the FT-1000MP and using a couple of inches of wire as an antenna on
>the
>KX3, on a quiet 10 meter band. The S-meter on the KX3 was 9+
>
>There is noticeable opposite (lower frequency) side suppression
>issues,
>but this cuts off at about 900 Hz
>
>On the higher side, I can hear signal to as far as my hearing and/or
>the
>audio chain permit. The most interesting note was that the undesired
>signal
>(high side only) takes a sharp dip or disappears every 50Hz, at .00 or
>.05
>on the frequency readout.
>
>I'm not sure what to make of all this, but FWIW . . .
>

Oliver Dröse

Re: KX3 Filter Blow-By

In reply to this post by Jimk8mr

Hi Jim,

okay, that's another effect you are experiencing. Sideband suppression on 10 & 6m was really bad on my KX3, too, just about 25 dB on 10 m and 10 dB on 6 m, but that was easily fixed with the OSB suppression by band field test firmware. It is probably going to be officially released soon. It will suppress the OSB by more than 60 dB per band if correctly done, I even have cases where I cannot hear the OSB anymore (seems like a wonder, hi) with an S9+20 main signal.

Luckily I do not experience your 50 Hz signal problem.

73, Olli - DH8BQA

----- Original Message -----
From: [hidden email]
To: [hidden email] ; [hidden email] ; [hidden email]
Sent: Tuesday, October 09, 2012 2:48 PM
Subject: Re: [Elecraft] KX3 Filter Blow-By

I did some more careful checking this morning, transmitting a few watts on the FT-1000MP and using a couple of inches of wire as an antenna on the KX3, on a quiet 10 meter band. The S-meter on the KX3 was 9+

There is noticeable opposite (lower frequency) side suppression issues, but this cuts off at about 900 Hz

On the higher side, I can hear signal to as far as my hearing and/or the audio chain permit. The most interesting note was that the undesired signal (high side only) takes a sharp dip or disappears every 50Hz, at .00 or .05 on the frequency readout.

I'm not sure what to make of all this, but FWIW . . .

73 - Jim K8MR

In a message dated 10/8/2012 3:29:37 P.M. Eastern Daylight Time, [hidden email] writes:
Hi Jim,

did you have VFO NR enabled by chance? I suppose yes, as the KX3 is quite
unusable on the high bands without. :-( There is a known issue = bad effect
of the DSP leading to "artifacts", i.e. hearing signals +/- 5-6 kHz again
from strong stations. If you turn off VFO NR it goes away, but then the VFO
noise is much too strong. :-( Another bad effect is even with VFO NR enabled
if you tune "over" strong stations you suddenly have strong VFO noise until
you stop turning the wheel. Afterwards it's gone again. And if you turn the
VFO fast enough you will not even recognize even 59+ signals. :-( All
problems from the VFO NR DSP implementation as confirmed by Elecraft. And no
matter if with or without roofing filter and with/without 8 kHz shift
enabled. Still wonder why nobody else is complaining about those effects?
Cannot be that everybody has an s4 noise level on 12, 10 & 6 m that would
mask the VFO noise and thus no need to enable VFO NR.

I documented all those effects on video and sent it over to Wayne. He said
he and Lyle are working on it, hopefully with some results soon, otherwise
the KX3 is of no use for a high band op like me. :-( Never seen such
problems with *any* other rig owned so far ...

73, Olli - DH8BQA

----- Original Message -----
From: <[hidden email]>
To: <[hidden email]>
Sent: Monday, October 08, 2012 7:46 PM
Subject: [Elecraft] KX3 Filter Blow-By

>A recent KX3 owner (# 1677), I've noticed hearing out of passband signals
> from loud CW stations. I can hear such stations up to several KHz away. I
> suspect the range is limited by the audio response of the system,
> including
> my ears. Both sides of zero beat, though less so on the opposite side of
> the zero beat.
>
> In the CA QSO Party this weekend, maybe the loudest 10% of the stations on
> 10 CW Saturday afternoon were leaking through. (I've heard the leakage on
> other bands as well.)
>
> I don't have any roofing filters. (I figured any stations weak enough for
> me to need the filter to hear, would never be able to hear me anyway).
>
> Is this normal, or is there some shielding or other issue affecting my
> unit? (It is a kit version).
>
>
> 73 - Jim K8MR
> ______________________________________________________________
> 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
>
>
> -----
> E-Mail ist virenfrei.
> Von AVG uberpruft - www.avg.de
> Version: 2012.0.2221 / Virendatenbank: 2441/5317 - Ausgabedatum:
> 08.10.2012
>

______________________________________________________________
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

E-Mail ist virenfrei.
Von AVG überprüft - www.avg.de
Version: 2012.0.2221 / Virendatenbank: 2441/5317 - Ausgabedatum: 08.10.2012
______________________________________________________________
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Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
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Bill W4ZV

Re: KX3 Filter Blow-By

In reply to this post by wayne burdick

What is the OSB suppression after calibration using this procedure?

73, Bill W4ZV

wayne burdick wrote

Hi Jim,

This is most likely related to opposite sideband suppression, not
filter blow-by. Nominal factory calibration results in OSB suppression
of around 55-60 dB. You can improve on this using a new procedure we
developed a month or so ago. It requires a strong signal source on
each band to be optimized. I can send you the firmware and
instructions if you're interested.

73,
Wayne
N6KR

On Oct 8, 2012, at 10:46 AM, [hidden email] wrote:

> A recent KX3 owner (# 1677), I've noticed hearing out of passband
> signals
> from loud CW stations. I can hear such stations up to several KHz
> away. I
> suspect the range is limited by the audio response of the system,
> including
> my ears. Both sides of zero beat, though less so on the opposite
> side of
> the zero beat.
>
> In the CA QSO Party this weekend, maybe the loudest 10% of the
> stations on
> 10 CW Saturday afternoon were leaking through. (I've heard the
> leakage on
> other bands as well.)
>
> I don't have any roofing filters. (I figured any stations weak
> enough for
> me to need the filter to hear, would never be able to hear me anyway).
>
> Is this normal, or is there some shielding or other issue affecting my
> unit? (It is a kit version).
>
>
> 73 - Jim K8MR
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wayne burdick

Re: KX3 Filter Blow-By

Administrator

You might see suppression of as high as 70-75 dB, but it varies a bit per-band and with signal pitch. The worst case will still be ~50-55 dB as with other receivers using the same direct-conversion I/Q architecture.

73,
Wayne
N6KR

On May 6, 2013, at 4:41 AM, Bill W4ZV <[hidden email]> wrote:

> What is the OSB suppression after calibration using this procedure?
>
> 73, Bill W4ZV
>
>
> wayne burdick wrote
>> Hi Jim,
>>
>> This is most likely related to opposite sideband suppression, not
>> filter blow-by. Nominal factory calibration results in OSB suppression
>> of around 55-60 dB. You can improve on this using a new procedure we
>> developed a month or so ago. It requires a strong signal source on
>> each band to be optimized. I can send you the firmware and
>> instructions if you're interested.
>>
>> 73,
>> Wayne
>> N6KR
>>
>> On Oct 8, 2012, at 10:46 AM,
>
>> Jimk8mr@
>
>> wrote:
>>
>>> A recent KX3 owner (# 1677), I've noticed hearing out of passband
>>> signals
>>> from loud CW stations. I can hear such stations up to several KHz
>>> away. I
>>> suspect the range is limited by the audio response of the system,
>>> including
>>> my ears. Both sides of zero beat, though less so on the opposite
>>> side of
>>> the zero beat.
>>>
>>> In the CA QSO Party this weekend, maybe the loudest 10% of the
>>> stations on
>>> 10 CW Saturday afternoon were leaking through. (I've heard the
>>> leakage on
>>> other bands as well.)
>>>
>>> I don't have any roofing filters. (I figured any stations weak
>>> enough for
>>> me to need the filter to hear, would never be able to hear me anyway).
>>>
>>> Is this normal, or is there some shielding or other issue affecting my
>>> unit? (It is a kit version).
>>>
>>>
>>> 73 - Jim K8MR
>>> ______________________________________________________________
>>> Elecraft mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:
>
>> Elecraft@.qth
>
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>
>> ______________________________________________________________
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>
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>>
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>
>
>
>
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