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Impossible mission? USB with the 13khz filter for PSK31 on Digipan

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Joe Subich, W4TV-4

Re: FM and AM Bandwidth

> I'd love an excuse to spring for a 13Khz roofing filter ;-)

The 13 KHz roofing filter with 4.2 KHz maximum audio frequency
sounds quite good now but I'm looking forward to a bit more
high end when Lyle gets it done. 6 KHz would be a very good
match to the 13 KHz filter but I'd be happy with 5.5 KHz.

73,

... Joe, W4TV

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Barry N1EU
> Sent: Friday, January 30, 2009 5:44 PM
> To: wayne burdick
> Cc: [hidden email]
> Subject: Re: [Elecraft] FM and AM Bandwidth
>
>
> On Fri, Jan 30, 2009 at 9:45 PM, wayne burdick
> <[hidden email]> wrote:
> >
> > On Jan 30, 2009, at 1:11 PM, Barry N1EU wrote:
> >
> >> Lyle Johnson wrote:
> >>>
> >>> In the case of AM, we will be increasing the upper audio
> frequency
> >>> response.
> >>>
> >> This is good news Lyle. I've been starting to enjoy what
> a great SWL
> >> radio the K3 is and a little more bandwidth will make it even
> >> greater!
> >
> > Meanwhile, try using SSB to copy AM signals. This uses the same
> > crystal filter (6 kHz) but allows for around 4 kHz of AF bandwidth.
>
> Thanks Wayne. Yes, I do that sometimes! I also sometimes
> listen with K3/LP-PAN/Winrad because the 5.5Khz AF and sync
> detector combo make for real listening pleasure.
>
> I'd love an excuse to spring for a 13Khz roofing filter ;-)
>
> 73,
> Barry N1EU

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Barry N1EU

Re: FM and AM Bandwidth

I'm seeing 4.1Khz max audio frequency on AM with my 6Khz roofing
filter. Perhaps Lyle is working a little magic?

73,
Barry N1EU

On Sat, Jan 31, 2009 at 2:00 AM, Joe Subich, W4TV <[hidden email]> wrote:

>
>
>> I'd love an excuse to spring for a 13Khz roofing filter ;-)
>
> The 13 KHz roofing filter with 4.2 KHz maximum audio frequency
> sounds quite good now but I'm looking forward to a bit more
> high end when Lyle gets it done. 6 KHz would be a very good
> match to the 13 KHz filter but I'd be happy with 5.5 KHz.
>
> 73,
>
> ... Joe, W4TV
>
>
>
>
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]] On Behalf Of Barry N1EU
>> Sent: Friday, January 30, 2009 5:44 PM
>> To: wayne burdick
>> Cc: [hidden email]
>> Subject: Re: [Elecraft] FM and AM Bandwidth
>>
>>
>> On Fri, Jan 30, 2009 at 9:45 PM, wayne burdick
>> <[hidden email]> wrote:
>> >
>> > On Jan 30, 2009, at 1:11 PM, Barry N1EU wrote:
>> >
>> >> Lyle Johnson wrote:
>> >>>
>> >>> In the case of AM, we will be increasing the upper audio
>> frequency
>> >>> response.
>> >>>
>> >> This is good news Lyle. I've been starting to enjoy what
>> a great SWL
>> >> radio the K3 is and a little more bandwidth will make it even
>> >> greater!
>> >
>> > Meanwhile, try using SSB to copy AM signals. This uses the same
>> > crystal filter (6 kHz) but allows for around 4 kHz of AF bandwidth.
>>
>> Thanks Wayne. Yes, I do that sometimes! I also sometimes
>> listen with K3/LP-PAN/Winrad because the 5.5Khz AF and sync
>> detector combo make for real listening pleasure.
>>
>> I'd love an excuse to spring for a 13Khz roofing filter ;-)
>>
>> 73,
>> Barry N1EU
>
>
>
>

Joe Subich, W4TV-4

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

In reply to this post by Joe Subich, W4TV-4

> I can only speak for Yaesu and Icom gear, but Yaesu
> rigs specify 5Khz transmit FM in their manuals and in
> the Icom 706MKIIG service manual states FM deviation
> is adjusted for 4.5Khz.

There is a BIG difference between FM deviation and
maximum modulating frequency (audio response). I was
speaking specifically to maximum modulating frequency.

As Lyle has said elsewhere, the maximum modulating
frequency in the K3 is limited to about 2.8 KHz - in
all modes except ESSB - which results in an occupied
bandwidth of about 15.5 KHz with 5 KHz of deviation
for FM.

> -----Original Message-----
> From: Thomas Tumino [mailto:[hidden email]]
> Sent: Friday, January 30, 2009 1:33 PM
> To: [hidden email]
> Subject: RE: [Elecraft] Impossible mission? USB with the
> 13khz filter for PSK31on Digipan
>
>
>
>
> No, typical transmitted bandwidth for communications use -
> including FM is about 100 Hz to 3000 Hz.
>
> I can only speak for Yaesu and Icom gear, but Yaesu
> rigs specify 5Khz transmit FM in their manuals and in
> the Icom 706MKIIG service manual states FM deviation
> is adjusted for 4.5Khz. I would assume
> this was the standard for all Yaesu and Icom gear
> at least. Some Yaesu rigs do have a special
> "FM-N" transmit mode of 2.5 Khz, similar to FRS radios,
> but I think that mode is the exception and not
> the rule.
> I think the DSP receive limit of 4Khz should at least
> be mentioned in the K3 materials (or perhaps it
> is and I missed it?). This bothers me as
> really I feel FM and AM are most regularly used
> to enjoy audio of a better quality then SSB audio,
> and a 4Khz limit cuts down on that a bit.
> 73 to all and thanks for your
> help,
> Tom-N2YTF
>
>

Tom-N2YTF

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

OK so are you saying that the K3 right now receives a maximum of FM 4Khz of AUDIO which translates into a received RF bandwidth of better then 5Khz, so there is no problem? If that is what you are saying then I think I got it now.

73,

Tom

Joe Subich, W4TV-4

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

> OK so are you saying that the K3 right now receives a maximum
> of FM 4Khz of AUDIO which translates into a received RF
> bandwidth of better then 5Khz, so there is no problem? If
> that is what you are saying then I think I got it now.

Please get a copy of The Radio Amateurs Handbook or other
technical text that describes the operation Frequency Modulation.
Explaining FM and the relationship of maximum modulating (audio)
frequency, deviation, and occupied (RF) bandwidth. In simple
terms they are related by Carson's Rule which says that
RF bandwidth is equal to twice the sum of the highest audio
(modulating) frequency plus the deviation.

In the K3 the RF bandwidth is fixed at 13 KHz (FM filter).

> -----Original Message-----
> From: Thomas Tumino [mailto:[hidden email]]
> Sent: Friday, January 30, 2009 11:23 PM
> To: [hidden email]; [hidden email]
> Subject: RE: [Elecraft] Impossible mission? USB with the
> 13khz filter for PSK31on Digipan
>
>
> > I can only speak for Yaesu and Icom gear, but Yaesu
> > rigs specify 5Khz transmit FM in their manuals and in
> > the Icom 706MKIIG service manual states FM deviation
> > is adjusted for 4.5Khz.
>
> There is a BIG difference between FM deviation and
> maximum modulating frequency (audio response). I was
> speaking specifically to maximum modulating frequency.
>
> As Lyle has said elsewhere, the maximum modulating
> frequency in the K3 is limited to about 2.8 KHz - in
> all modes except ESSB - which results in an occupied
> bandwidth of about 15.5 KHz with 5 KHz of deviation
> for FM.
>
> OK so are you saying that the K3 right now receives a maximum
> of FM 4Khz of AUDIO which translates into a received RF
> bandwidth of better then 5Khz, so there is no problem? If
> that is what you are saying then I think I got it now.
>
> 73,
> Tom
>
>
>
>
>
> > -----Original Message-----
> > From: Thomas Tumino [mailto:[hidden email]]
> > Sent: Friday, January 30, 2009 1:33 PM
> > To: [hidden email]
> > Subject: RE: [Elecraft] Impossible mission? USB with the
> > 13khz filter for PSK31on Digipan
> >
> >
> >
> >
> > No, typical transmitted bandwidth for communications use -
> > including FM is about 100 Hz to 3000 Hz.
> >
> > I can only speak for Yaesu and Icom gear, but Yaesu
> > rigs specify 5Khz transmit FM in their manuals and in
> > the Icom 706MKIIG service manual states FM deviation
> > is adjusted for 4.5Khz. I would assume
> > this was the standard for all Yaesu and Icom gear
> > at least. Some Yaesu rigs do have a special
> > "FM-N" transmit mode of 2.5 Khz, similar to FRS radios,
> > but I think that mode is the exception and not
> > the rule.
> > I think the DSP receive limit of 4Khz should at least
> > be mentioned in the K3 materials (or perhaps it
> > is and I missed it?). This bothers me as
> > really I feel FM and AM are most regularly used
> > to enjoy audio of a better quality then SSB audio,
> > and a 4Khz limit cuts down on that a bit.
> > 73 to all and thanks for your
> > help,
> > Tom-N2YTF
> >
> >
>

Tom-N2YTF

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

In reply to this post by Joe Subich, W4TV-4

Thanks Joe for setting me straight on that. It has been years since I had read about it.

So I guess this is only a PSK31 issue (or any software with panoramic receive) with an external computer, and minimal at that...still it would be nice...

73,

Tom

--- On Fri, 1/30/09, Joe Subich, W4TV <[hidden email]> wrote:

From: Joe Subich, W4TV <[hidden email]>
Subject: RE: [Elecraft] Impossible mission? USB with the 13khz filter for PSK31on Digipan
To: [hidden email], [hidden email]
Date: Friday, January 30, 2009, 9:10 PM

> I can only speak for Yaesu and Icom gear, but Yaesu 
> rigs specify 5Khz transmit FM in their manuals and in
> the Icom 706MKIIG service manual states FM deviation
> is adjusted for 4.5Khz.

There is a BIG difference between FM deviation and 
maximum modulating frequency (audio response).  I was 
speaking specifically to maximum modulating frequency. 

As Lyle has said elsewhere, the maximum modulating 
frequency in the K3 is limited to about 2.8 KHz - in 
all modes except ESSB - which results in an occupied 
bandwidth of about 15.5 KHz with 5 KHz of deviation 
for FM.  





> -----Original Message-----
> From: Thomas Tumino [mailto:[hidden email]] 
> Sent: Friday, January 30, 2009 1:33 PM
> To: [hidden email]
> Subject: RE: [Elecraft] Impossible mission? USB with the 
> 13khz filter for PSK31on Digipan
> 
> 
> 
> 
> No, typical transmitted bandwidth for communications use - 
> including FM is about 100 Hz to 3000 Hz.  
> 
> I can only speak for Yaesu and Icom gear, but Yaesu 
> rigs specify 5Khz transmit FM in their manuals and in
> the Icom 706MKIIG service manual states FM deviation
> is adjusted for 4.5Khz.  I would assume
> this was the standard for all Yaesu and Icom gear
> at least.  Some Yaesu rigs do have a special 
> "FM-N" transmit mode of 2.5 Khz, similar to FRS radios,
> but I think that mode is the exception and not 
> the rule. 
> I think the DSP receive limit of 4Khz should at least
> be mentioned in the K3 materials (or perhaps it 
> is and I missed it?).  This bothers me as
> really I feel FM and AM are most regularly used 
> to enjoy audio of a better quality then SSB audio, 
> and a 4Khz limit cuts down on that a bit.
> 73 to all and thanks for your
>  help,
> Tom-N2YTF
>  
>

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AD6XY

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

Has anyone tried taking the K3s 2nd IF out to a high end soundcard and doing the DSP on a PC?

Don Wilhelm-4

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

I don't think there are any soundcards capable of handling the 8+ MHz IF
output from the K3, but LP-PAN converts that IF signal down to baseband
and does exactly what you are asking about with PowerSDR.

73,
Don W3FPR

AD6XY wrote:

> Has anyone tried taking the K3s 2nd IF out to a high end soundcard and doing
> the DSP on a PC?
>
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
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>

ab2tc

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

The 2nd IF is 15kHz which is well within the capabilities of many sound cards. But it would require surgery to the K3 as this signal is not available externally. It would certainly be an interesting experiment for the bold risk taker. Most PC SDR software needs an I/Q pair of signals which this is not, but there is software that will take a single signal elevated above baseband (I believe Softrock works this way).

Don Wilhelm-4 wrote

I don't think there are any soundcards capable of handling the 8+ MHz IF
output from the K3, but LP-PAN converts that IF signal down to baseband
and does exactly what you are asking about with PowerSDR.

73,
Don W3FPR

AD6XY wrote:
> Has anyone tried taking the K3s 2nd IF out to a high end soundcard and doing
> the DSP on a PC?

Joe Subich, W4TV-4

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

> Most PC SDR software needs an I/Q pair of signals which this
> is not, but there is software that will take a single signal
> elevated above baseband (I believe Softrock works this way).

The SoftRock receivers and LP-Pan operate much the same way.
They are fixed frequency downconverters that provide I/Q audio
outputs. The I/Q audio is then applied to a common soundcard.
The higher quality soundcards provide a wider frequency "window"
(higher sample rates), lower noise floor/higher dynamic range,
and better image rejection (better I/Q balance).

73,

... Joe, W4TV

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of ab2tc
> Sent: Saturday, January 31, 2009 11:49 AM
> To: [hidden email]
> Subject: Re: [Elecraft] Impossible mission? USB with the
> 13khz filter for PSK31on Digipan
>
>
>
> The 2nd IF is 15kHz which is well within the capabilities of
> many sound cards. But it would require surgery to the K3 as
> this signal is not available externally. It would certainly
> be an interesting experiment for the bold risk taker. Most PC
> SDR software needs an I/Q pair of signals which this is not,
> but there is software that will take a single signal elevated
> above baseband (I believe Softrock works this way).
>
>
> Don Wilhelm-4 wrote:
> >
> > I don't think there are any soundcards capable of handling
> the 8+ MHz
> > IF
> > output from the K3, but LP-PAN converts that IF signal down
> to baseband
> > and does exactly what you are asking about with PowerSDR.
> >
> > 73,
> > Don W3FPR
> >
> > AD6XY wrote:
> >> Has anyone tried taking the K3s 2nd IF out to a high end soundcard
> >> and doing the DSP on a PC?
> >
> >
>
>
> -----
> AB2TC - Knut
> --
> View this message in context:
> http://n2.nabble.com/Impossible-mission--USB-with-the-13khz-fi

lter-for-PSK31-on-Digipan-tp2240355p2250439.html
Sent from the Elecraft mailing list archive at Nabble.com.

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Joe Subich, W4TV-4

Re: Impossible mission? USB with the 13khz filter for PSK31on Digipan

In reply to this post by Tom-N2YTF

I don't even see it as an issue ... even with those receivers
that produce audio to 6 KHz (for DigiPan 2.0), the transmitter
will be limited to 2.8 or 3 KHz audio input anyway due to the
bandwidth of the transmit IF filter. Without checking, I believe
the K3's transmit audio (DATA A mode) is 200 - 2800 Hz just like
any other properly designed transceiver.

73,

... Joe, W4TV

> -----Original Message-----
> From: Thomas Tumino [mailto:[hidden email]]
> Sent: Saturday, January 31, 2009 10:26 AM
> To: [hidden email]; [hidden email]
> Subject: RE: [Elecraft] Impossible mission? USB with the
> 13khz filter for PSK31on Digipan
>
>
> Thanks Joe for setting me straight on that. It has been
> years since I had read about it.
>
> So I guess this is only a PSK31 issue (or any software with
> panoramic receive) with an external computer, and minimal at
> that...still it would be nice...
>
> 73,
> Tom
>
>
> --- On Fri, 1/30/09, Joe Subich, W4TV <[hidden email]> wrote:
>
> From: Joe Subich, W4TV <[hidden email]>
> Subject: RE: [Elecraft] Impossible mission? USB with the
> 13khz filter for PSK31on Digipan
> To: [hidden email], [hidden email]
> Date: Friday, January 30, 2009, 9:10 PM
>
>
> > I can only speak for Yaesu and Icom gear, but Yaesu
> > rigs specify 5Khz transmit FM in their manuals and in
> > the Icom 706MKIIG service manual states FM deviation
> > is adjusted for 4.5Khz.
>
> There is a BIG difference between FM deviation and
> maximum modulating frequency (audio response). I was
> speaking specifically to maximum modulating frequency.
>
> As Lyle has said elsewhere, the maximum modulating
> frequency in the K3 is limited to about 2.8 KHz - in
> all modes except ESSB - which results in an occupied
> bandwidth of about 15.5 KHz with 5 KHz of deviation
> for FM.
>
>
>
>
>
> > -----Original Message-----
> > From: Thomas Tumino [mailto:[hidden email]]
> > Sent: Friday, January 30, 2009 1:33 PM
> > To: [hidden email]
> > Subject: RE: [Elecraft] Impossible mission? USB with the
> > 13khz filter for PSK31on Digipan
> >
> >
> >
> >
> > No, typical transmitted bandwidth for communications use -
> > including FM is about 100 Hz to 3000 Hz.
> >
> > I can only speak for Yaesu and Icom gear, but Yaesu
> > rigs specify 5Khz transmit FM in their manuals and in
> > the Icom 706MKIIG service manual states FM deviation
> > is adjusted for 4.5Khz. I would assume
> > this was the standard for all Yaesu and Icom gear
> > at least. Some Yaesu rigs do have a special
> > "FM-N" transmit mode of 2.5 Khz, similar to FRS radios,
> > but I think that mode is the exception and not
> > the rule.
> > I think the DSP receive limit of 4Khz should at least
> > be mentioned in the K3 materials (or perhaps it
> > is and I missed it?). This bothers me as
> > really I feel FM and AM are most regularly used
> > to enjoy audio of a better quality then SSB audio,
> > and a 4Khz limit cuts down on that a bit.
> > 73 to all and thanks for your
> > help,
> > Tom-N2YTF
> >
> >
>