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K3 LoCut/HiCut

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GARY-2

K3 LoCut/HiCut

Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.
Gary
N6LRV
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Mike KS7D

Re: K3 LoCut/HiCut

Gary,

See page 14 "Filter Controls" and page 23 "Filter Passband Controls of the Owner's Manual.

Mike, ks7d

On Nov 24, 2010, at 3:53 PM, <[hidden email]> wrote:

> Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.
> Gary
> N6LRV
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Nate Bargmann

Re: K3 LoCut/HiCut

In reply to this post by GARY-2

* On 2010 24 Nov 14:55 -0600, [hidden email] wrote:
> Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.

Gary, it may be easier to visualize each control manipulating a variable
high pass and low pass filter. The Lo Cut cuts off low frequencies, or
rather, sets the cutoff frequency of a high pass filter. The Hi Cut
does likewise, except it controls the cutoff frequency of a low pass
filter. They allow you to adjust either side of the passband
independently. You can acheive the same thing with the Width and Shift
controls it's just that the way the K3 is set up using Width works well
on CW as it adjusts both cutoff frequencies but maintains a constant
center frequency of the passband. On SSB using either the Lo or Hi Cut
controls can significantly reduce QRM from one side or the other.

On my recently departed FT-920 only the Lo and Hi Cut controls were
available in the DSP. I like the K3's selection of either way of doing
it depending on the situation. Over this past SSB Sweepstakes I found
the Lo/Hi Cut indespensible for digging stations from between others.

Experiment!

73, de Nate N0NB >>

--

"The optimist proclaims that we live in the best of all
possible worlds. The pessimist fears this is true."

Ham radio, Linux, bikes, and more: http://n0nb.us/index.html
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N5GE

Re: K3 LoCut/HiCut

In reply to this post by GARY-2

I see that the question has been answered, but I would like to tell you how I
find the answers to questions about operating the K3.

I keep a copy of the LATEST K3 operating manual on my desk-top (computer).

When I get confused about how something works or want to learn what it's for, I
use the find functionality of Adobe Reader to search for the answer in the
manual.

For example: Searching for the words "low cut" takes one to explanations on page
23.

Searching for "filter controls" takes one to pages 5, 9, 14, and 23.

After, or while reading the information on those pages and trying them out as I
do, so I get a pretty good idea of their purpose.

Please don't interpret this as an admonition. It is meant to advise.

On Wed, 24 Nov 2010 12:53:32 -0800, <[hidden email]> wrote:

73,

Tom Childers
Radio Amateur N5GE
Licensed since 1976
QCWA Member 35102
ARRL Life Member

>Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.
>Gary
>N6LRV
>______________________________________________________________
[snip]

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Amateur Radio Operator N5GE

N5GE

Re: K3 LoCut/HiCut

In reply to this post by Nate Bargmann

Nate,

Your explanation is excellent.

One of the things I miss in the Rice Box Radio manuals are the diagrams used to
describe this type of thing. Sometimes a picture really is worth a thousand
words.

73,

Tom Childers
Radio Amateur N5GE
Licensed since 1976
QCWA Member 35102
ARRL Life Member

On Wed, 24 Nov 2010 15:31:38 -0600, Nate Bargmann <[hidden email]> wrote:

>* On 2010 24 Nov 14:55 -0600, [hidden email] wrote:
>> Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.
>
>Gary, it may be easier to visualize each control manipulating a variable
>high pass and low pass filter. The Lo Cut cuts off low frequencies, or
>rather, sets the cutoff frequency of a high pass filter. The Hi Cut
>does likewise, except it controls the cutoff frequency of a low pass
>filter. They allow you to adjust either side of the passband
>independently. You can acheive the same thing with the Width and Shift
>controls it's just that the way the K3 is set up using Width works well
>on CW as it adjusts both cutoff frequencies but maintains a constant
>center frequency of the passband. On SSB using either the Lo or Hi Cut
>controls can significantly reduce QRM from one side or the other.
>
>On my recently departed FT-920 only the Lo and Hi Cut controls were
>available in the DSP. I like the K3's selection of either way of doing
>it depending on the situation. Over this past SSB Sweepstakes I found
>the Lo/Hi Cut indespensible for digging stations from between others.
>
>Experiment!
>
>73, de Nate N0NB >>

Amateur Radio Operator N5GE

Ramiro Aceves

Re: K3 LoCut/HiCut

Hi K3 fans

Speaking about HI and LO Cut controls. I have notice this:

Tune a carrier at for example, 1 KHz tone.
Set a computer waterfall with enough frequency resolution to see few Hz
changes
Play with HI and LO Cut controls up and down (of course, let the 1 KHz
signal pass trough the filter).

Result, the carrier frecuency will be shifted by a few Hz.

Do you hace same results in your K3?

Do Low and Hi Cut controls only have effect on the DSP filters?

Thanks, Ramiro.

EA4NZ

Amateur Radio Operator N5GE escribió:

> Nate,
>
> Your explanation is excellent.
>
> One of the things I miss in the Rice Box Radio manuals are the diagrams used to
> describe this type of thing. Sometimes a picture really is worth a thousand
> words.
>
> 73,
>
> Tom Childers
> Radio Amateur N5GE
> Licensed since 1976
> QCWA Member 35102
> ARRL Life Member
>
>
> On Wed, 24 Nov 2010 15:31:38 -0600, Nate Bargmann <[hidden email]> wrote:
>
>> * On 2010 24 Nov 14:55 -0600, [hidden email] wrote:
>>> Would someone please explain the purpose and function of the low cut and high cut controls on the K3? There doesn't seem to be any explanation I can find in the current user's manual and I'd like to make sure I'm understanding their function correctly because the response I see on the P3 passband icon contridicts what I expected to see occur when increasing or decreasing either setting. Thanks very much.
>> Gary, it may be easier to visualize each control manipulating a variable
>> high pass and low pass filter. The Lo Cut cuts off low frequencies, or
>> rather, sets the cutoff frequency of a high pass filter. The Hi Cut
>> does likewise, except it controls the cutoff frequency of a low pass
>> filter. They allow you to adjust either side of the passband
>> independently. You can acheive the same thing with the Width and Shift
>> controls it's just that the way the K3 is set up using Width works well
>> on CW as it adjusts both cutoff frequencies but maintains a constant
>> center frequency of the passband. On SSB using either the Lo or Hi Cut
>> controls can significantly reduce QRM from one side or the other.
>>
>> On my recently departed FT-920 only the Lo and Hi Cut controls were
>> available in the DSP. I like the K3's selection of either way of doing
>> it depending on the situation. Over this past SSB Sweepstakes I found
>> the Lo/Hi Cut indespensible for digging stations from between others.
>>
>> Experiment!
>>
>> 73, de Nate N0NB >>
>
> ______________________________________________________________
> 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
>

Nate Bargmann

Re: K3 LoCut/HiCut

In reply to this post by N5GE

* On 2010 24 Nov 15:44 -0600, Amateur Radio Operator N5GE wrote:
>
> Nate,
>
> Your explanation is excellent.

Accept my humble thanks. :-)

> One of the things I miss in the Rice Box Radio manuals are the diagrams used to
> describe this type of thing. Sometimes a picture really is worth a thousand
> words.

I recall the TS-830S manual having graphics describing functions such as
the VBT and Notch very well. With the ubiquity of YouTube and other
Internet video, such descriptions can be improved and made readily
available.

73, de Nate N0NB >>

--

"The optimist proclaims that we live in the best of all
possible worlds. The pessimist fears this is true."

Ham radio, Linux, bikes, and more: http://n0nb.us/index.html
______________________________________________________________
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Nate Bargmann

Re: K3 LoCut/HiCut

In reply to this post by Ramiro Aceves

* On 2010 24 Nov 16:04 -0600, Ramiro Aceves wrote:

> Hi K3 fans
>
> Speaking about HI and LO Cut controls. I have notice this:
>
> Tune a carrier at for example, 1 KHz tone.
> Set a computer waterfall with enough frequency resolution to see few Hz
> changes
> Play with HI and LO Cut controls up and down (of course, let the 1 KHz
> signal pass trough the filter).
>
> Result, the carrier frecuency will be shifted by a few Hz.
>
> Do you hace same results in your K3?

Yes. If you don't want FC to change, switch to the Width/Shift controls.
It's a feature, not a bug (TM).

> Do Low and Hi Cut controls only have effect on the DSP filters?

I would presume so as my understanding is that all of this "magic" takes
place in the DSP and the crystal filters operate at a fixed offset, if
required.

73, de Nate N0NB >>

--

"The optimist proclaims that we live in the best of all
possible worlds. The pessimist fears this is true."

Ham radio, Linux, bikes, and more: http://n0nb.us/index.html
______________________________________________________________
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GARY-2

Re: K3 LoCut/HiCut

In reply to this post by Nate Bargmann

Thanks Nate. The audible effects are as I expected them to be when adjusting
low or high cut but the visual representations on both the K3 and the P3
were not and had me a bit confused. I'll continue to experiment.
73,
Gary

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Nate Bargmann
Sent: Wednesday, November 24, 2010 1:32 PM
To: [hidden email]
Subject: Re: [Elecraft] K3 LoCut/HiCut

Gary, it may be easier to visualize each control manipulating a variable
high pass and low pass filter. The Lo Cut cuts off low frequencies, or
rather, sets the cutoff frequency of a high pass filter. The Hi Cut
does likewise, except it controls the cutoff frequency of a low pass
filter. They allow you to adjust either side of the passband
independently. You can acheive the same thing with the Width and Shift
controls it's just that the way the K3 is set up using Width works well
on CW as it adjusts both cutoff frequencies but maintains a constant
center frequency of the passband. On SSB using either the Lo or Hi Cut
controls can significantly reduce QRM from one side or the other.

On my recently departed FT-920 only the Lo and Hi Cut controls were
available in the DSP. I like the K3's selection of either way of doing
it depending on the situation. Over this past SSB Sweepstakes I found
the Lo/Hi Cut indespensible for digging stations from between others.

Experiment!

73, de Nate N0NB >>

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Nate Bargmann

Re: K3 LoCut/HiCut

* On 2010 24 Nov 20:34 -0600, Gary wrote:
> Thanks Nate. The audible effects are as I expected them to be when adjusting
> low or high cut but the visual representations on both the K3 and the P3
> were not and had me a bit confused. I'll continue to experiment.

The display only has a relatively few segments compared to the steps and
runs out of display segments rapidly. The dark segments represent the
relative passband bandwidth based on the mode. If the passband is
centered then the segments will be centered over the arrows below the
line the passband segments "sit" on. If higher then the segments will
be to the right and if lower then to the left.

Mostly it's just a nice visual aid showing the relative passband width
and shift. The real information is in the VFO B display when the
settings are changed.

HTH,

73, de Nate N0NB >>

--

"The optimist proclaims that we live in the best of all
possible worlds. The pessimist fears this is true."

Ham radio, Linux, bikes, and more: http://n0nb.us/index.html
______________________________________________________________
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Don Wilhelm-4

Re: K3 LoCut/HiCut

In reply to this post by GARY-2

Gary,

The HiCut and LoCut are quite useful for SSB. To maintain
intelligibilty while the width is narrowed, the low end must remain at
about 300 Hz, while the High end can be reduced dramatically.

For use with CW, the shift and width controls are more useful - just
reduce the width, and the center frequency stays the same (usually at
your sidetone pitch). Slight changes in the shift control may be in
order, but normally it will remain fixed.

73,
Don W3FPR

On 11/24/2010 9:32 PM, Gary wrote:

> Thanks Nate. The audible effects are as I expected them to be when adjusting
> low or high cut but the visual representations on both the K3 and the P3
> were not and had me a bit confused. I'll continue to experiment.
> 73,
> Gary
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Nate Bargmann
> Sent: Wednesday, November 24, 2010 1:32 PM
> To: [hidden email]
> Subject: Re: [Elecraft] K3 LoCut/HiCut
>
> Gary, it may be easier to visualize each control manipulating a variable
> high pass and low pass filter. The Lo Cut cuts off low frequencies, or
> rather, sets the cutoff frequency of a high pass filter. The Hi Cut
> does likewise, except it controls the cutoff frequency of a low pass
> filter. They allow you to adjust either side of the passband
> independently. You can acheive the same thing with the Width and Shift
> controls it's just that the way the K3 is set up using Width works well
> on CW as it adjusts both cutoff frequencies but maintains a constant
> center frequency of the passband. On SSB using either the Lo or Hi Cut
> controls can significantly reduce QRM from one side or the other.
>
> On my recently departed FT-920 only the Lo and Hi Cut controls were
> available in the DSP. I like the K3's selection of either way of doing
> it depending on the situation. Over this past SSB Sweepstakes I found
> the Lo/Hi Cut indespensible for digging stations from between others.
>
> Experiment!
>
> 73, de Nate N0NB>>
>
>
> ______________________________________________________________
> 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
>

Ramiro Aceves

Re: K3 LoCut/HiCut

In reply to this post by Nate Bargmann

Hi all

Changing HI/LO, SHIFT/WIDTH produce a few Hz change in the tunning
frequency. Obviously it does not matter but here we have the waterfall:

http://ea1abz.ure.es/Hz-change.png

73, Ramiro.

Nate Bargmann escribió:

> * On 2010 24 Nov 16:04 -0600, Ramiro Aceves wrote:
>> Hi K3 fans
>>
>> Speaking about HI and LO Cut controls. I have notice this:
>>
>> Tune a carrier at for example, 1 KHz tone.
>> Set a computer waterfall with enough frequency resolution to see few Hz
>> changes
>> Play with HI and LO Cut controls up and down (of course, let the 1 KHz
>> signal pass trough the filter).
>>
>> Result, the carrier frecuency will be shifted by a few Hz.
>>
>> Do you hace same results in your K3?
>
> Yes. If you don't want FC to change, switch to the Width/Shift controls.
> It's a feature, not a bug (TM).
>
>> Do Low and Hi Cut controls only have effect on the DSP filters?
>
> I would presume so as my understanding is that all of this "magic" takes
> place in the DSP and the crystal filters operate at a fixed offset, if
> required.
>
> 73, de Nate N0NB >>
>