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Setting shift for different filters?

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David F. Reed-2

Setting shift for different filters?

I note that as expected, the center frequency of the bandpass of any
given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter,
the 2.7 KHz filter or the 2.1 KHz filter.

This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
So the 2.1 KHz filter (without using the shift control) passes 450 Hz to
2.55 KHz, right?

I note that if I shift the center of the filter down to 1.35 KHz, the
voices are more intelligible...

When I switch filters and get back to the 2.1 KHz filter, the shift is
lost; is there a setting I can use to save that shift setting?

Thanks & 73 de W5SV, Dave
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Don Wilhelm-4

Re: Setting shift for different filters?

Dave,

Yes, the default is 1500 Hz. with a 2.8 kHz filter, that puts the low
end at 200 Hz and the high end at 2900 Hz.

AND that is why you should be using the Hi-Cut, Lo-Cut on SSB instead of
Shift and Width.

For good intelligibility, you need to have some content in the 300 Hz
range, so set the Lo-Cut to 200, 250, or 300 depending on your desires
and the QRM conditions. Then change only the Hi-Cut to reduce the
filter width - the width will change, cutting the highs and the filter
center frequency will be automatically changed leaving the low frequency
end unchanged.

You will find that you can use a filter as narrow as 1500 Hz and still
maintain SSB intelligibility (for a male voice, a female voice may need
a few more highs). Using Width and Shift to accomplish the same thing
is possible, but requires a lot more "knob fiddling".

73,
Don W3FPR

On 2/29/2012 6:38 PM, David F. Reed wrote:

> I note that as expected, the center frequency of the bandpass of any
> given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter,
> the 2.7 KHz filter or the 2.1 KHz filter.
>
> This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
> So the 2.1 KHz filter (without using the shift control) passes 450 Hz to
> 2.55 KHz, right?
>
> I note that if I shift the center of the filter down to 1.35 KHz, the
> voices are more intelligible...
>
> When I switch filters and get back to the 2.1 KHz filter, the shift is
> lost; is there a setting I can use to save that shift setting?
>
> Thanks& 73 de W5SV, Dave
> ______________________________________________________________
> 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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Help: http://mailman.qth.net/mmfaq.htm
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David F. Reed-2

Re: Setting shift for different filters?

Don,

thanks for the reply.

1. when I try using the Lo-Cut, it seems to be confined to 100 Hz
increments, so, 150, 250, 350, but no 200, 300, or 100 available; is
there a way to set that differently?
2. I can accomplish the same thing either way if I understand what is
going on, but is there a way to preserve the setting?

Thanks again.

--Dave W5SV

On 2/29/12 7:18 PM, Don Wilhelm wrote:

> Dave,
>
> Yes, the default is 1500 Hz. with a 2.8 kHz filter, that puts the low
> end at 200 Hz and the high end at 2900 Hz.
>
> AND that is why you should be using the Hi-Cut, Lo-Cut on SSB instead
> of Shift and Width.
>
> For good intelligibility, you need to have some content in the 300 Hz
> range, so set the Lo-Cut to 200, 250, or 300 depending on your desires
> and the QRM conditions. Then change only the Hi-Cut to reduce the
> filter width - the width will change, cutting the highs and the filter
> center frequency will be automatically changed leaving the low
> frequency end unchanged.
>
> You will find that you can use a filter as narrow as 1500 Hz and still
> maintain SSB intelligibility (for a male voice, a female voice may
> need a few more highs). Using Width and Shift to accomplish the same
> thing is possible, but requires a lot more "knob fiddling".
>
> 73,
> Don W3FPR
>
> On 2/29/2012 6:38 PM, David F. Reed wrote:
>> I note that as expected, the center frequency of the bandpass of any
>> given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter,
>> the 2.7 KHz filter or the 2.1 KHz filter.
>>
>> This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
>> So the 2.1 KHz filter (without using the shift control) passes 450 Hz to
>> 2.55 KHz, right?
>>
>> I note that if I shift the center of the filter down to 1.35 KHz, the
>> voices are more intelligible...
>>
>> When I switch filters and get back to the 2.1 KHz filter, the shift is
>> lost; is there a setting I can use to save that shift setting?
>>
>> Thanks& 73 de W5SV, Dave
>> ______________________________________________________________
>> 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
>>

k5oai

Re: Setting shift for different filters?

hold SHIFT knob til you see <- NORM ->
if you turn the WIDTH knob to an odd number 2.5 2.7 2.9 3.1 etc

tap SHIFT or WIDTH knob so the LOW and HI leds comes on
if you turn the SHIFT or WIDTH knob
you will see LO .05 .15 .25 etc

now again
hold SHIFT knob til you see <- NORM ->
this time turn knob WIDTH to any even number 2.4 2.6 2.8 etc

tap SHIFT or WIDTH knob so the LOW and HI leds comes on
if you turn the SHIFT or WIDTH knob
you will see LO .10 .20 .30 etc

as for a way to keep a setting after you have found one you like

I use the I setting for a <- NORM -> 2.7 FC *1.50

I Hold the WIDTH knob to get to filter setting II
now this one I play with the LO and HI until I find a setting I like

now I can use I for normal wide easy listening on a clear band
and I change to II if I need a modifier 300 LO to 2.10 HI narrow setting

ymmv
GB & 73
K5OAI
Sam Morgan

On 2/29/2012 8:16 PM, David F. Reed wrote:

> Don,
>
> thanks for the reply.
>
> 1. when I try using the Lo-Cut, it seems to be confined to 100 Hz
> increments, so, 150, 250, 350, but no 200, 300, or 100 available; is
> there a way to set that differently?
> 2. I can accomplish the same thing either way if I understand what is
> going on, but is there a way to preserve the setting?
>
> Thanks again.
>
> --Dave W5SV
>
>
> On 2/29/12 7:18 PM, Don Wilhelm wrote:
>> Dave,
>>
>> Yes, the default is 1500 Hz. with a 2.8 kHz filter, that puts the low
>> end at 200 Hz and the high end at 2900 Hz.
>>
>> AND that is why you should be using the Hi-Cut, Lo-Cut on SSB instead
>> of Shift and Width.
>>
>> For good intelligibility, you need to have some content in the 300 Hz
>> range, so set the Lo-Cut to 200, 250, or 300 depending on your desires
>> and the QRM conditions. Then change only the Hi-Cut to reduce the
>> filter width - the width will change, cutting the highs and the filter
>> center frequency will be automatically changed leaving the low
>> frequency end unchanged.
>>
>> You will find that you can use a filter as narrow as 1500 Hz and still
>> maintain SSB intelligibility (for a male voice, a female voice may
>> need a few more highs). Using Width and Shift to accomplish the same
>> thing is possible, but requires a lot more "knob fiddling".
>>
>> 73,
>> Don W3FPR
>>
>> On 2/29/2012 6:38 PM, David F. Reed wrote:
>>> I note that as expected, the center frequency of the bandpass of any
>>> given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter,
>>> the 2.7 KHz filter or the 2.1 KHz filter.
>>>
>>> This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
>>> So the 2.1 KHz filter (without using the shift control) passes 450 Hz to
>>> 2.55 KHz, right?
>>>
>>> I note that if I shift the center of the filter down to 1.35 KHz, the
>>> voices are more intelligible...
>>>
>>> When I switch filters and get back to the 2.1 KHz filter, the shift is
>>> lost; is there a setting I can use to save that shift setting?
>>>
>>> Thanks& 73 de W5SV, Dave

Don Wilhelm-4

Re: Setting shift for different filters?

In reply to this post by David F. Reed-2

David,

OK, I have perhaps ignored the subtle points - in some cases, you will
have 50 Hz rounding and in other cases, you will have 100 Hz rounding -
that makes little difference. 50 Hz to a SSB low frequency response
does not make much difference.

n 2/29/2012 9:16 PM, David F. Reed wrote:

> Don,
>
> thanks for the reply.
>
> 1. when I try using the Lo-Cut, it seems to be confined to 100 Hz
> increments, so, 150, 250, 350, but no 200, 300, or 100 available;
> is there a way to set that differently?
> 2. I can accomplish the same thing either way if I understand what is
> going on, but is there a way to preserve the setting?
>
> Thanks again.
>
> --Dave W5SV
>
>
> On 2/29/12 7:18 PM, Don Wilhelm wrote:
>> Dave,
>>
>> Yes, the default is 1500 Hz. with a 2.8 kHz filter, that puts the
>> low end at 200 Hz and the high end at 2900 Hz.
>>
>> AND that is why you should be using the Hi-Cut, Lo-Cut on SSB instead
>> of Shift and Width.
>>
>> For good intelligibility, you need to have some content in the 300 Hz
>> range, so set the Lo-Cut to 200, 250, or 300 depending on your
>> desires and the QRM conditions. Then change only the Hi-Cut to
>> reduce the filter width - the width will change, cutting the highs
>> and the filter center frequency will be automatically changed leaving
>> the low frequency end unchanged.
>>
>> You will find that you can use a filter as narrow as 1500 Hz and
>> still maintain SSB intelligibility (for a male voice, a female voice
>> may need a few more highs). Using Width and Shift to accomplish the
>> same thing is possible, but requires a lot more "knob fiddling".
>>
>> 73,
>> Don W3FPR
>>
>> On 2/29/2012 6:38 PM, David F. Reed wrote:
>>> I note that as expected, the center frequency of the bandpass of any
>>> given filter on SSB seems to be 1.5 KHz, whether its the 6 KHz filter,
>>> the 2.7 KHz filter or the 2.1 KHz filter.
>>>
>>> This seems to work out to be passing from 150 Hz to 2.85 KHz, right?
>>> So the 2.1 KHz filter (without using the shift control) passes 450
>>> Hz to
>>> 2.55 KHz, right?
>>>
>>> I note that if I shift the center of the filter down to 1.35 KHz, the
>>> voices are more intelligible...
>>>
>>> When I switch filters and get back to the 2.1 KHz filter, the shift is
>>> lost; is there a setting I can use to save that shift setting?
>>>
>>> Thanks& 73 de W5SV, Dave
>>> ______________________________________________________________
>>> 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
>>>

Don Wilhelm-4

Re: Setting shift for different filters?

In reply to this post by David F. Reed-2

Dave,

A 50 Hz difference will not make a significant difference in the
received audio unless you have greater than average ears.
You can "preserve the setting using the Norm I and Norm2 settings, but
for the most part, I just use the Lo-Cut and Hi-Cut knobs to dial in
what is best for the current situation at hand.

73,
Don W3FPR

On 2/29/2012 9:16 PM, David F. Reed wrote:

David F. Reed-2

Re: Setting shift for different filters?

In reply to this post by k5oai

Thanks Sam, that solves that part of my question.

73 de Dave, W5SV

On 2/29/12 8:48 PM, Sam Morgan wrote:

> hold SHIFT knob til you see<- NORM ->
> if you turn the WIDTH knob to an odd number 2.5 2.7 2.9 3.1 etc
>
> tap SHIFT or WIDTH knob so the LOW and HI leds comes on
> if you turn the SHIFT or WIDTH knob
> you will see LO .05 .15 .25 etc
>
> now again
> hold SHIFT knob til you see<- NORM ->
> this time turn knob WIDTH to any even number 2.4 2.6 2.8 etc
>
> tap SHIFT or WIDTH knob so the LOW and HI leds comes on
> if you turn the SHIFT or WIDTH knob
> you will see LO .10 .20 .30 etc
>
>
> as for a way to keep a setting after you have found one you like
>
> I use the I setting for a<- NORM -> 2.7 FC *1.50
>
> I Hold the WIDTH knob to get to filter setting II
> now this one I play with the LO and HI until I find a setting I like
>
> now I can use I for normal wide easy listening on a clear band
> and I change to II if I need a modifier 300 LO to 2.10 HI narrow setting
>
> ymmv
> GB& 73
> K5OAI
> Sam Morgan

David F. Reed-2

Re: Setting shift for different filters?

In reply to this post by Don Wilhelm-4

Don,

thanks; my ears are worse than normal, not better, so not a problem,
just ab observation. And I finally got it worked out how to use the
Norm settings, so all is well now.

It seems I am still learning my way around my K3, and will be for some
time; it keeps amazing me at how versatile and how good a radio it is.

73 de Dave, W5SV

On 2/29/12 9:09 PM, Don Wilhelm wrote:

> Dave,
>
> A 50 Hz difference will not make a significant difference in the
> received audio unless you have greater than average ears.
> You can "preserve the setting using the Norm I and Norm2 settings, but
> for the most part, I just use the Lo-Cut and Hi-Cut knobs to dial in
> what is best for the current situation at hand.
>
> 73,
> Don W3FPR