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K3 DIY DSP Rev D - please elaborate

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DOUGLAS ZWIEBEL

K3 DIY DSP Rev D - please elaborate

OK...so besides the LPF, what else is different on the DSP "D" board?
I don't think I've seen any elaboration anywhere.

thanks,
de Doug KR2Q
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DaveL G3TJP

Re: K3 DIY DSP Rev D - please elaborate

Gleaned from this reflector, I'm only aware of the lowering of the bass rolloff frequency. Elecraft and W9AC did it in different ways, although only W9AC's changes are published.

73 & HNY DaveL G3TJP
OK...so besides the LPF, what else is different on the DSP "D" board?
I don't think I've seen any elaboration anywhere.

thanks,
de Doug KR2Q
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Ralph Parker

Re: K3 DIY DSP Rev D - please elaborate

In reply to this post by DOUGLAS ZWIEBEL

>...so besides the LPF, what else is different on the DSP "D" board?
>I don't think I've seen any elaboration anywhere.

I've asked this question before with no answer so far.
I'd like some kind of 'sales talk' so I know what I'm getting.
"It's really good - buy it." is not enough.

VE7XF

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Johnny Siu

Re： K3 DIY DSP Rev D - please elaborate

Hello Ralph,

Yes, good question.

In fact, I really want to know:

1. Will there be any differences in the key RX specifications (i.e. BDR and MDS, survival among strong big guns) if DSP Rev D is installed?

2. From the bit and piece of information scattered among the emails in this forum and the Elecraft web pages, I have been given to understand that the modifications are related to the cut off point of the high end and extension of the low end of the audio specturm. Is my understanding correct?

3. If my understanding is correct, I suppose the TX and RX EQ in the menu of K3 can address the audio issue.

4. If my understanding is NOT correct, what is actual benefit of all those DSP board modification which cannot be addressed in the audio section i.e. TX and RX EQ?

I think Elecraft should set out in a table in their website comparing the before Vs after modifications in terms of performance of K3. I agree with you that "It's really good - buy it." is not enough. I don't mind paying the extras for the modifications but need to know precisely what I am paying for.

73 & HNY,

Johnny VR2XMC

----- 郵件原件 ----
寄件人﹕ Ralph Parker <[hidden email]>
收件人﹕ [hidden email]
傳送日期﹕ 2010/1/1 (五) 4:48:10 PM
主題： Re: [Elecraft] K3 DIY DSP Rev D - please elaborate

>...so besides the LPF, what else is different on the DSP "D" board?
>I don't think I've seen any elaboration anywhere.

I've asked this question before with no answer so far.
I'd like some kind of 'sales talk' so I know what I'm getting.
"It's really good - buy it." is not enough.

VE7XF

Yahoo!香港提供網上安全攻略，教你如何防範黑客! 請前往 http://hk.promo.yahoo.com/security/ 了解更多!

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juergen piezo

Re: Re： K3 DIY DSP Rev D - please elaborate

Hi Johnny

I have seen many subtle improvements in the K3's receiver with the many successive firmware upgrades. There is no supporting documentary evidence from Elecraft for these subtle changes or improvements that I have noticed.

I have worn out a coaxial switch comparing and testing K3's to other radios. When you have access to as many K3's as I do, all with different serial numbers with which you can play with, upgrade and compare. They belong to my radio club BTW. The improvements that I am seeing is not entirely in my imagination. I am sure that many of the improvements comes about because of better DSP techniques and algorithms thats implemented and not mentioned by Elecraft.

SDR techniques and how they are applied to an individual product is not an exact science. I am sure Elecraft has developed many of its own techniques and algorithms for its DSP library. These will never ever be revealed or discussed as its their intellectual property.

I own a Watkins Johnson HF1000 and it was returned several times to their factory for updates. The receiver would return and the DSP and receiver would be magically better. When I discussed this once on the phone with one of their engineers, his comments were that that they were improving and tesing new DSP techniques all the time. His comments were also that these would never be discussed nor would the information ever be released to the public. I am sure its the same with Elecraft.

Another product like this with propriety DSP techniques is the Perseus, I am sure that there are many who would like to get their hands on some of Niko's code. I had the opportunity to compare a Rohde-Schwarz DSP receiver to the Perseus, and let me tell you that the Perseus was a lot better. Now if a company like Rohde-Schwarz cant beat a one man show like Microtelecom it tells you that DSP programming is not as straightforward as many want you to believe especially when it applies to HF receivers.

I think the best bet is to keep your K3 updated with all the mods and upgrades. You will be getting many things for free thats not even mentioned. The small price for the DSP upgrade is minimal compared to what other companies would be charging you for a similar upgrade, thats if you would even get such an opportunity. Certainly if it came from Yaesu or Icom you would have to ship the radio back to the factory. Look at the costly exercise that FT9000 owners went through for the PEP and factory upgrade program. By all accounts that transformed the FT9000 into a new radio.

If you own a K3, the ticket price for continual improvement is beer money.
While I have to also pay expensive shipping, I still consider it to be cheap way out for a better product in the end analysis. I certainly will be trying and upgrading all our clubs K3's with the upgraded DSP board.

73
John

--- On Fri, 1/1/10, Johnny Siu <[hidden email]> wrote:

> From: Johnny Siu <[hidden email]>
> Subject: [Elecraft] Re： K3 DIY DSP Rev D - please elaborate
> To: "Ralph Parker" <[hidden email]>, [hidden email]
> Date: Friday, January 1, 2010, 1:38 AM
> Hello Ralph,
>
> Yes, good question.
>
> In fact, I really want to know:
>
> 1. Will there be any differences in the key RX
> specifications (i.e. BDR and MDS, survival among strong big
> guns) if DSP Rev D is installed?
>
> 2. From the bit and piece of information scattered among
> the emails in this forum and the Elecraft web pages, I have
> been given to understand that the modifications are related
> to the cut off point of the high end and extension of the
> low end of the audio specturm. Is my understanding
> correct?
>
> 3. If my understanding is correct, I suppose the TX and
> RX EQ in the menu of K3 can address the audio issue.
>
> 4. If my understanding is NOT correct, what is actual
> benefit of all those DSP board modification which cannot be
> addressed in the audio section i.e. TX and RX EQ?
>
> I think Elecraft should set out in a table in their website
> comparing the before Vs after modifications in terms
> of performance of K3. I agree with you that "It's really
> good - buy it." is not enough. I don't mind paying the
> extras for the modifications but need to know precisely what
> I am paying for.
>
> 73 & HNY,
>
> Johnny VR2XMC
>
>
>
> ----- 郵件原件 ----
> 寄件人﹕ Ralph Parker <[hidden email]>
> 收件人﹕ [hidden email]
> 傳送日期﹕ 2010/1/1 (五) 4:48:10 PM
> 主題： Re: [Elecraft] K3 DIY DSP Rev D - please
> elaborate
>
> >...so besides the LPF, what else is different on the
> DSP "D" board?
> >I don't think I've seen any elaboration anywhere.
>
> I've asked this question before with no answer so far.
> I'd like some kind of 'sales talk' so I know what I'm
> getting.
> "It's really good - buy it." is not enough.
>
> VE7XF
>
>
>
> Yahoo!香港提供網上安全攻略，教你如何防範黑客!
> 請前往 http://hk.promo.yahoo.com/security/
> 了解更多!
>
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> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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> Please help support this email list: http://www.qsl.net/donate.html

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Johnny Siu

Re： Re： K3 DIY DSP Rev D - please elaborate

Hello John,

Thanks for your comments and I understand what you would like to express.

However, I agree with the previous writer, VE7XF, that Elecraft should tell us the difference of DSP Rev D before Vs after modification. All the information is just piece meal and scattered among emails and Elecraft website.

I know it must be good, otherwise, no modification is required. However, Elecraft should tell me how good it will be, BDR, MDS ??? Of course, I owned a K3 and still have a K2, I understand the continuous improvement of Elecraft products. Again, as a customer, I still like to know what benefit I shall get from the DSP Rev D modification.

Similar to every firmware upgrade, Elecraft gives a brief description of the improved areas. So, why should they not do the same for the DSP Rev D modification?

The answer to my questions in my previous email should be simple and will only take Elecraft a few minutes to address them. They are the designers and well known why modifications are required and what benefits can be achieved.

I am not a radio man by profession and really want to learn more radio knowledge from them so as to educate myself.

73 & HNY

Johnny Siu VR2XMC

----- 郵件原件 ----
寄件人﹕ juergen <[hidden email]>
收件人﹕ [hidden email]
傳送日期﹕ 2010/1/1 (五) 6:47:37 PM
主題： Re: [Elecraft] Re： K3 DIY DSP Rev D - please elaborate

Hi Johnny

I have seen many subtle improvements in the K3's receiver with the many successive firmware upgrades. There is no supporting documentary evidence from Elecraft for these subtle changes or improvements that I have noticed.

I have worn out a coaxial switch comparing and testing K3's to other radios. When you have access to as many K3's as I do, all with different serial numbers with which you can play with, upgrade and compare. They belong to my radio club BTW.. The improvements that I am seeing is not entirely in my imagination. I am sure that many of the improvements comes about because of better DSP techniques and algorithms thats implemented and not mentioned by Elecraft.

SDR techniques and how they are applied to an individual product is not an exact science. I am sure Elecraft has developed many of its own techniques and algorithms for its DSP library. These will never ever be revealed or discussed as its their intellectual property.

I own a Watkins Johnson HF1000 and it was returned several times to their factory for updates. The receiver would return and the DSP and receiver would be magically better. When I discussed this once on the phone with one of their engineers, his comments were that that they were improving and tesing new DSP techniques all the time. His comments were also that these would never be discussed nor would the information ever be released to the public. I am sure its the same with Elecraft.

Another product like this with propriety DSP techniques is the Perseus, I am sure that there are many who would like to get their hands on some of Niko's code. I had the opportunity to compare a Rohde-Schwarz DSP receiver to the Perseus, and let me tell you that the Perseus was a lot better. Now if a company like Rohde-Schwarz cant beat a one man show like Microtelecom it tells you that DSP programming is not as straightforward as many want you to believe especially when it applies to HF receivers.

I think the best bet is to keep your K3 updated with all the mods and upgrades. You will be getting many things for free thats not even mentioned. The small price for the DSP upgrade is minimal compared to what other companies would be charging you for a similar upgrade, thats if you would even get such an opportunity. Certainly if it came from Yaesu or Icom you would have to ship the radio back to the factory. Look at the costly exercise that FT9000 owners went through for the PEP and factory upgrade program. By all accounts that transformed the FT9000 into a new radio.

If you own a K3, the ticket price for continual improvement is beer money.
While I have to also pay expensive shipping, I still consider it to be cheap way out for a better product in the end analysis. I certainly will be trying and upgrading all our clubs K3's with the upgraded DSP board.

73
John

--- On Fri, 1/1/10, Johnny Siu <[hidden email]> wrote:

Yahoo!香港提供網上安全攻略，教你如何防範黑客! 請前往 http://hk.promo.yahoo.com/security/ 了解更多!

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Don Wilhelm-4

Re: Re： K3 DIY DSP Rev D - please elaborate

In reply to this post by juergen piezo

I believe the firmware release notes reveal everything that has been
improved/changed with each release. I see no need for Elecraft to
document the algorithms.

73,
Don W3FPR

juergen wrote:
> Hi Johnny
>
> I have seen many subtle improvements in the K3's receiver with the many successive firmware upgrades. There is no supporting documentary evidence from Elecraft for these subtle changes or improvements that I have noticed.
>
>
>
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Bill W4ZV

Re: Re： Re： K3 DIY DSP Rev D - please elaborate

In reply to this post by Johnny Siu

Johnny Siu wrote

I know it must be good, otherwise, no modification is required. However, Elecraft should tell me how good it will be, BDR, MDS ???

Johnny I believe I can safely say absolutely ZERO difference in major specs like BDR, MDS, IMDDR3, etc. These are all determined well ahead of the DSP audio stage. I believe the main difference is in audio bandwidth only...extension of the low end response and attenuation of high end DSP artifacts. If you like ESSB or are bothered by the 12 kHz artifacts, then you might want the mod.

Personally I'm waiting for someone with two units (one with the mod and one without) to post some audio recordings before I go to the bother and expense of this mod. BTW I have done ALL other mods but I'm not at all convinced this one will make any difference to me since I don't do ESSB and I don't hear any artifacts in the headphones I use, even though a hearing test confirms I still have good hearing at high frequencies.

73 & HNY!

Bill

N5GE

Re: Re? Re? K3 DIY DSP Rev D - please elaborate

In reply to this post by Johnny Siu

On Fri, 1 Jan 2010 20:53:14 +0800 (HKT), Johnny Siu
<[hidden email]> wrote:

[snip]
>I owned a K3 and still have a K2,
[snip]
>I still like to know what benefit I shall get from the DSP Rev D modification.
[snip]

You will not receive any benefit from the revision. You don't have a
K3 to install it in.

73 and best regards to you and your family in the new year.

Tom, N5GE

[hidden email]
K3 #806 with SUB RX, K3 #1055, PR6,
XV144, XV432, KRC2,
W1, 2 W2's and other small kits

1 K144XV on order

http://www.n5ge.com
http://www.swotrc.net

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Amateur Radio Operator N5GE

DaveL G3TJP

Re: K3 DIY DSP Rev D - please elaborate

In reply to this post by DOUGLAS ZWIEBEL

By firmware release notes, do you mean the comments associated with the order for the K3DSPUPGD, Don? If that's a yes, then this should settle matters because it says:

"Improves low freq RX/TX audio response below 300 Hz, and adds a Low Pass Filter (LPF) that rolls off RX audio above 4 kHz."

Thanks for your guidance on this, Don. A Happy New Year to you and to all on the reflector.

73 DaveL G3TJP
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Don Wilhelm-4

Re: K3 DIY DSP Rev D - please elaborate

David,

Yes, that answers it about the DSP board upgrade - there will be a note
there if there is a hardware change that requires updated firmware to
realize the upgraded function. Normally, the firmware is "backwards
compatible" meaning that the updated firmware will run on K3s without
the hardware upgrade.
I was really commenting to the gentleman who seemed to be having a
problem locating documentation about what was included in each firmware
release (upgrade) - perhaps I misunderstood his question (statement?).

73,
Don W3FPR

David Lankshear wrote:
> By firmware release notes, do you mean the comments associated with the order for the K3DSPUPGD, Don? If that's a yes, then this should settle matters because it says:
>
> "Improves low freq RX/TX audio response below 300 Hz, and adds a Low Pass Filter (LPF) that rolls off RX audio above 4 kHz."
>
> Thanks for your guidance on this, Don. A Happy New Year to you and to all on the reflector.
>
> 73 DaveL G3TJP
>
>
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Johnny Siu

K3 DSP Rev D - some of the findings

In reply to this post by N5GE

Hello Group,

Thanks to all the emails "off-the-list" answering my questions about the the benefit of DSP Rev D modification.

Although none of those emails is officially from Elecraft, I would summarize the findings as follows:

1. the modifications will have no effect on the key RX performances such as BDR, IMD, MDS etc;
2. the modifications are related to the artifacts in audio spectrum generated from the DSP;
3. some of the K3 users do not have problems the DSP artifacts even without the DSP Rev D modifications because they didn't even hear the artifacts;
4. for those K3 users who can hear the artifacts, the modifications did lessen their listen fatigue;
5. the modifications may be also useful for those users who would like ESSB

I have thanked all those replied to me off the list individually. Should I miss any of you from the reply list, please forgive my oversight.

This group is wonderful. I have been given the chance to learn more radio knowledge from the experts who in fact gave me personal attention by answering my questions off-the-list.

Of course, some of you may find my questions are 'baby standard' or even 'why border to ask?' If it were the case, please relax a bit and give me, a NON-RADIO man by profession, the chance to ask and educate myself.

73 & HNY,

Johnny Siu VR2XMC

Yahoo!香港提供網上安全攻略，教你如何防範黑客! 請前往 http://hk.promo.yahoo.com/security/ 了解更多!

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juergen piezo

Re: K3 DSP Rev D - some of the findings

Hi Johnny

You might also want to read about why some aspects of the K3.'s performance makes it sound harsh. Some interesting information on Marks blog page. Mark is not the only person that has observed that the K2 sounds "sweeter" than the K3 on weak signal CW.

Mark also found that there was less ringing on the Ten Tec Orion's narrow DSP filters. DSP algorithms and how they are implemented play an important role as to how a radio ultimately performs. Here is an example where it is has been measured.

http://pa5mw.blogspot.com/

I have seen no comment that the DSP revision D board improves Inband IMD. It will be interesting to see if it does improve RX inband IMD.

73

John

--- On Fri, 1/1/10, Johnny Siu <[hidden email]> wrote:

> From: Johnny Siu <[hidden email]>
> Subject: [Elecraft] K3 DSP Rev D - some of the findings
> To: [hidden email], [hidden email]
> Date: Friday, January 1, 2010, 4:17 PM
> Hello Group,
>
> Thanks to all the emails "off-the-list" answering my
> questions about the the benefit of DSP Rev D modification.
>
> Although none of those emails is officially from Elecraft,
> I would summarize the findings as follows:
>
> 1. the modifications will have no effect on the key RX
> performances such as BDR, IMD, MDS etc;
> 2. the modifications are related to the artifacts in audio
> spectrum generated from the DSP;
> 3. some of the K3 users do not have problems the DSP
> artifacts even without the DSP Rev D modifications because
> they didn't even hear the artifacts;
> 4. for those K3 users who can hear the artifacts, the
> modifications did lessen their listen fatigue;
> 5. the modifications may be also useful for those users who
> would like ESSB
>
> I have thanked all those replied to me off the list
> individually. Should I miss any of you from the reply
> list, please forgive my oversight.
>
> This group is wonderful. I have been given the chance
> to learn more radio knowledge from the experts who in fact
> gave me personal attention by answering my questions
> off-the-list.
>
> Of course, some of you may find my questions are 'baby
> standard' or even 'why border to ask?' If it were the
> case, please relax a bit and give me, a NON-RADIO man by
> profession, the chance to ask and educate myself.
>
> 73 & HNY,
>
> Johnny Siu VR2XMC
>
>
>
> Yahoo!香港提供網上安全攻略，教你如何防範黑客!
> 請前往 http://hk.promo.yahoo.com/security/
> 了解更多!
>
> ______________________________________________________________
> 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 DSP Rev D - some of the findings

juergen piezo wrote

Mark also found that there was less ringing on the Ten Tec Orion's narrow DSP filters.

Note that:

"The above (Orion) 200Hz and 100Hz DSP filter settings are 227Hz and 155Hz in reality.

This is a key reason there is less ringing. If I recall correctly, the DSP 50 (lowest setting) in the K3 is actually around 70-80 Hz, which is about half of the Orion DSP 100 (lowest setting).

73, Bill

Brett Howard

Re: Re： Re： K3 DIY DSP Rev D - please elaborate

In reply to this post by Bill W4ZV

Honestly I didn't think I was hearing all that much in the way of
artifacts and I even recorded audio from the K3 and applied filtering to
it and didn't really hear a lot of A/B comparison difference.

However I noticed that the audio is MUCH less fatiguing when listening
to the K3 since I installed the LP daughter board on my DSP board.

~Brett (KC7OTG)

On Fri, 2010-01-01 at 05:35 -0800, Bill W4ZV wrote:

>
>
> Johnny Siu wrote:
> >
> > I know it must be good, otherwise, no modification is required.
> > However, Elecraft should tell me how good it will be, BDR, MDS ???
> >
>
> Johnny I believe I can safely say absolutely ZERO difference in major specs
> like BDR, MDS, IMDDR3, etc. These are all determined well ahead of the DSP
> audio stage. I believe the main difference is in audio bandwidth
> only...extension of the low end response and attenuation of high end DSP
> artifacts. If you like ESSB or are bothered by the 12 kHz artifacts, then
> you might want the mod.
>
> Personally I'm waiting for someone with two units (one with the mod and one
> without) to post some audio recordings before I go to the bother and expense
> of this mod. BTW I have done ALL other mods but I'm not at all convinced
> this one will make any difference to me since I don't do ESSB and I don't
> hear any artifacts in the headphones I use, even though a hearing test
> confirms I still have good hearing at high frequencies.
>
> 73 & HNY!
>
> Bill
>
> --
> View this message in context: http://n2.nabble.com/K3-DIY-DSP-Rev-D-please-elaborate-tp4238598p4239477.html
> Sent from the Elecraft mailing list archive at Nabble.com.
> ______________________________________________________________
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>
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> Please help support this email list: http://www.qsl.net/donate.html

Guy, K2AV

Re: Re： Re： K3 DIY DSP Rev D - please elaborate

Wish there was a way to analyze and quantify "MUCH less fatiguing".

There are aspects of hearing that are poorly understood. For instance there
is emerging cellphone research that indicates that listening to speech in
one ear is much more attention consuming than listening to the same
conversation in an open room.

It might be something of our nature that our brain expects to hear high
sound components in a particular phase relationship that decodes into
source and position and if the phase and "spatial" relationship is not
present in high frequency audio it occupies the brain's "attention" and
"energy" trying to decode it, much like the eye strain that comes from being
unable to focus on an image.

I know I find it very hard to listen to CW for any period of time that is
only in one ear. What other kinds of reactions to audio are there that are
not common knowledge?

73, Guy.

On Fri, Jan 1, 2010 at 9:47 PM, Brett Howard <[hidden email]>wrote:

> Honestly I didn't think I was hearing all that much in the way of
> artifacts and I even recorded audio from the K3 and applied filtering to
> it and didn't really hear a lot of A/B comparison difference.
>
> However I noticed that the audio is MUCH less fatiguing when listening
> to the K3 since I installed the LP daughter board on my DSP board.
>
> ~Brett (KC7OTG)
>
> On Fri, 2010-01-01 at 05:35 -0800, Bill W4ZV wrote:
> >
> >
> > Johnny Siu wrote:
> > >
> > > I know it must be good, otherwise, no modification is required.
> > > However, Elecraft should tell me how good it will be, BDR, MDS ???
> > >
> >
> > Johnny I believe I can safely say absolutely ZERO difference in major
> specs
> > like BDR, MDS, IMDDR3, etc. These are all determined well ahead of the
> DSP
> > audio stage. I believe the main difference is in audio bandwidth
> > only...extension of the low end response and attenuation of high end DSP
> > artifacts. If you like ESSB or are bothered by the 12 kHz artifacts,
> then
> > you might want the mod.
> >
> > Personally I'm waiting for someone with two units (one with the mod and
> one
> > without) to post some audio recordings before I go to the bother and
> expense
> > of this mod. BTW I have done ALL other mods but I'm not at all convinced
> > this one will make any difference to me since I don't do ESSB and I don't
> > hear any artifacts in the headphones I use, even though a hearing test
> > confirms I still have good hearing at high frequencies.
> >
> > 73 & HNY!
> >
> > Bill
> >
> > --
> > View this message in context:
> http://n2.nabble.com/K3-DIY-DSP-Rev-D-please-elaborate-tp4238598p4239477.html
> > Sent from the Elecraft mailing list archive at Nabble.com.
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