Elecraft › [K3]

K3 Filter problem Part II

Classic

List

Threaded

10 messages Options

k1tl

K3 Filter problem Part II

Hi Gang,

Failed to mention that when the filter switches above 2.1KHz, the tone moves
up the band and ditto when above 2.7KHz, the tone moves up a few KHz on the
band....annoying to say the least...so the problem may be somewhere else in
the K3.

Tom/k1tl...

______________________________________________________________
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 Filter problem Part II

k1tl wrote

Hi Gang,

Failed to mention that when the filter switches above 2.1KHz, the tone moves
up the band and ditto when above 2.7KHz, the tone moves up a few KHz on the
band....annoying to say the least...so the problem may be somewhere else in

The movement is caused because your 2.7k 5-pole has a different IF offset than the other 8-poles, which have zero offset. The fact that the tone is "reverse" passband means that it's an image. Have you tried CONFIG: SIG RMV?

73, Bill

Bill W4ZV

Re: K3 Filter problem Part II

Bill W4ZV wrote

Have you tried CONFIG: SIG RMV?

This was implemented in MCU 3.03 / DSP 2.10, 3-17-2009...documentation here:

http://www.elecraft.com/K3/k3_software.htm

(K3 Firmware Release Notes, just above "New Firmware Load Information")

73, Bill

Richard Ferch

Re: K3 Filter problem Part II

In reply to this post by k1tl

Bill W4ZV wrote:

> Bill W4ZV wrote:
>>
>> Have you tried CONFIG: SIG RMV?
>>
>
> This was implemented in MCU 3.03 / DSP 2.10, 3-17-2009...documentation here:
>
> http://www.elecraft.com/K3/k3_software.htm
>
> (K3 Firmware Release Notes, just above "New Firmware Load Information")
>
> 73, Bill

Warning: CONFIG:SIG RMV can have side effects. In addition to moving
fast-moving birdies right outside the bandpass, effectively eliminating
them, it also moves real signals by a smaller amount.

The net effect is that as you tune slowly past a carrier or CW signal,
instead of hearing a steady increase or decrease in pitch as you tune,
you can hear a sudden step in the frequency. If you have overdone the
SIG RMV, you may even find yourself hearing the same CW signal at the
same pitch at more than one dial reading, or conversely, finding it
impossible to tune a CW signal to a particular pitch because of a SIG
RMV frequency jump.

The bottom line is that you need to use this feature with care.

There may be another solution to these birdies, and that would be to try
adjusting the positions of the TMP cables that connect the main and sub
receivers to the KREF3 and KSYN3 boards. IIRC, the positions of these
cables can affect the strength of these birdies, which may help explain
why some people have fewer problems with them than others.

73,
Rich VE3KI
K3 #1595
______________________________________________________________
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

wayne burdick

Re: K3 Filter problem Part II

Administrator

SIG RMV does not move "real" signals. It shifts the internal signal
sources such that the net is zero. All you will hear is a slight
change in filter center pitch.

That said, it should, as you noted be used after checking cable
orientation.

73,
Wayne
N6KR

----
http://www.elecraft.com

On Oct 12, 2009, at 7:47 AM, Richard Ferch <[hidden email]> wrote:

> Bill W4ZV wrote:
>> Bill W4ZV wrote:
>>>
>>> Have you tried CONFIG: SIG RMV?
>>>
>>
>> This was implemented in MCU 3.03 / DSP 2.10,
>> 3-17-2009...documentation here:
>>
>> http://www.elecraft.com/K3/k3_software.htm
>>
>> (K3 Firmware Release Notes, just above "New Firmware Load
>> Information")
>>
>> 73, Bill
>
> Warning: CONFIG:SIG RMV can have side effects. In addition to moving
> fast-moving birdies right outside the bandpass, effectively
> eliminating
> them, it also moves real signals by a smaller amount.

______________________________________________________________
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

k1tl

Re: K3 Filter problem Part II

In reply to this post by k1tl

The problem seems to be inherent to the K3 itself and not the cabling as I
moved them around and the tone does not move at all.

Upon that, just wondering if "loose hardware" (i.e., screws, standoffs, etc)
could be causing the problem. Right now, it is not a show stopper, just a
little annoyance especially if a signal is on or near that frequency. I have
them on several other bands as well but not as strong as the "S2" signal on
15m.

Since 15m is open to EU/AF, I am going to spend the aftn trying to work some
DX after a long hiatus of that band for DX, then I'll take the K3 apart and
see if any loose hdwe.

73
Tom/k1tl...

______________________________________________________________
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

Richard Ferch

Re: K3 Filter problem Part II

In reply to this post by wayne burdick

Aha, looking at it more closely, I now see that it it only happens when
PB CTRL is set to SHIFT=.01, in either CW or DATA mode.

Oops! I just re-read the firmware release notes for MCU version 3.25,
which say that CONFIG:PB CTRL is not compatible with CONFIG:SIG RMV. No
doubt that's the problem here.

My apologies, then - it does not happen in the default configuration,
but with the current version of the firmware it happens when you have
CONFIG:PB CTRL set to SHIFT=.01 .

So I'd suggest to Tom that he check to make sure CONFIG:PB CTRL is set
to SHIFT=.05 before using CONFIG:SIG RMV. However, given his description
of a "reverse-direction" birdie, SIG RMV is definitely worth trying on
that birdie.

73,
Rich VE3KI

Wayne Burdick wrote:

> SIG RMV does not move "real" signals. It shifts the internal signal
> sources such that the net is zero. All you will hear is a slight change
> in filter center pitch.
>
> That said, it should, as you noted be used after checking cable
> orientation.
>
> 73,
> Wayne
> N6KR
>
> ----
> http://www.elecraft.com
>
> On Oct 12, 2009, at 7:47 AM, Richard Ferch <[hidden email]> wrote:
>
>> Bill W4ZV wrote:
>>> Bill W4ZV wrote:
>>>>
>>>> Have you tried CONFIG: SIG RMV?
>>>>
>>>
>>> This was implemented in MCU 3.03 / DSP 2.10,
>>> 3-17-2009...documentation here:
>>>
>>> http://www.elecraft.com/K3/k3_software.htm
>>>
>>> (K3 Firmware Release Notes, just above "New Firmware Load Information")
>>>
>>> 73, Bill
>>
>> Warning: CONFIG:SIG RMV can have side effects. In addition to moving
>> fast-moving birdies right outside the bandpass, effectively eliminating
>> them, it also moves real signals by a smaller amount.
>

k1tl

Re: K3 Filter problem Part II

In reply to this post by k1tl

Hi Gang,

Problem solved. Took top/bottom panels off and re-tightened all hdwe. Took
the KRX3 sub out and tightened whatever I could find. The TMP cables seemed
to be in the proper positions according to the photo in the KRX3 book. I
reseated all the TMP cables and noticed that TWO OF THE CABLES WERE NOT
PROPERLY SEATED...AHA ! !

After putting all together, turned on the K3 and no more "carrier" on the
15m band...........or anywhere else ! !

Many, many thanks to all who helped me on this one.

73 all

Tom/k1tl...

______________________________________________________________
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

Arie Kleingeld PA3A-2

K3 NR praise and question

All,

About the NR.
YES, the new algorithms really work! I can even dig out the weak CW sigs
better.

Now my question.
I use the first NR settings (1-1 to 4-4) in CW and the mixed ones for SSB.
Switching mode from ssb to cw and back again means switching NR setting
every time. I happen to switch modes a lot.

Wouldn't it be nice if the NR setting was coupled to the mode?
(some like the NB settings, they are saved per band)
Or is there some menu-item to switch this on already?

Thanks in advance.

73
Arie PA3A

______________________________________________________________
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

wayne burdick

Re: K3 NR praise and question

Administrator

On my task list.

73,
Wayne
N6KR

On Oct 12, 2009, at 1:28 PM, Arie Kleingeld PA3A wrote:

> All,
>
> About the NR.
> YES, the new algorithms really work! I can even dig out the weak CW
> sigs
> better.
>
> Now my question.
> I use the first NR settings (1-1 to 4-4) in CW and the mixed ones
> for SSB.
> Switching mode from ssb to cw and back again means switching NR
> setting
> every time. I happen to switch modes a lot.
>
> Wouldn't it be nice if the NR setting was coupled to the mode?
> (some like the NB settings, they are saved per band)
> Or is there some menu-item to switch this on already?
>
>
> Thanks in advance.
>
>
> 73
> Arie PA3A