KUSB Noise Query - K3

[john petters]

Hi Folks,
I posted a query about K3 Serial ports a few months back - we could not
get the K3 to work properly with the RS232 connection. It turned out to
be a fault with the sound card, which took out the serial connections.
When I first built the K3, I bought a cheap Prolific USB converter,
which radiates awful noise over the spectrum. I decided to bite the
bullet and buy the proper lead, which arrived today.

Using my Toshiba laptop, on battery power, I get a couple of s points of
noise on 10M with the KUSB connected and HRD fired up. This is using my
2 element DJ4VM quad, which is fed with 300 ohm twin into the shack,
i.e. near the laptop.

On LF, I can hear the pulsing information, in sympathy with the flashing
LEDs on the KUSB on 160M at quite a high level. I can even detect this
when fed into a Marconi dummy load. The K3 and the tuning units are
bonder to an RF earth - a copper stake about 8 feet away from the K3.

I have tried choking the USB lead at the laptop end, which does reduce
the noise to a degree.

The question I have is - am I being unrealistic in expecting zero noise
to be radiated from these adaptors?
Does anyone else have this problem - or has anyone looked for it?

It is not very noticeable on CW or SSB. To hear it best, listen in the
AM mode with the AGC off. On SSB it sounds like band noise.

Is this a problem JUST with USB adaptors or can I expect silence when
connecting a computer via RS232 to RS232.

If not we are sacrificing a low noise floor for the convenience of
computer control.

Any views appreciated,

73




--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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[mzilmer]

USB uses differential signaling.  Your problem may not be conductive noise, but instead it could be radiated directly from the adapter, where the ferrite won't help.

KeySpan makes a USB - serial adapter that is pretty much noise-free.  Its model  is HS19, I think.

Matt Zilmer
Consultant - Product Management Dept.
Magellan Navigation / MiTAC Digital Corp.
Tel: [phone]
Cell: [phone]
In status quo voluntas non sufficit


-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of john petters
Sent: Thursday, December 13, 2012 9:25 AM
To: [hidden email]
Subject: [Elecraft] KUSB Noise Query - K3

Hi Folks,
I posted a query about K3 Serial ports a few months back - we could not get the K3 to work properly with the RS232 connection. It turned out to be a fault with the sound card, which took out the serial connections.
When I first built the K3, I bought a cheap Prolific USB converter, which radiates awful noise over the spectrum. I decided to bite the bullet and buy the proper lead, which arrived today.

Using my Toshiba laptop, on battery power, I get a couple of s points of noise on 10M with the KUSB connected and HRD fired up. This is using my
2 element DJ4VM quad, which is fed with 300 ohm twin into the shack, i.e. near the laptop.

On LF, I can hear the pulsing information, in sympathy with the flashing LEDs on the KUSB on 160M at quite a high level. I can even detect this when fed into a Marconi dummy load. The K3 and the tuning units are bonder to an RF earth - a copper stake about 8 feet away from the K3.

I have tried choking the USB lead at the laptop end, which does reduce the noise to a degree.

The question I have is - am I being unrealistic in expecting zero noise to be radiated from these adaptors?
Does anyone else have this problem - or has anyone looked for it?

It is not very noticeable on CW or SSB. To hear it best, listen in the AM mode with the AGC off. On SSB it sounds like band noise.

Is this a problem JUST with USB adaptors or can I expect silence when connecting a computer via RS232 to RS232.

If not we are sacrificing a low noise floor for the convenience of computer control.

Any views appreciated,

73




--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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[n9adg]

You may try a different K-USB. I have a K-USB that radiated terrible noise on 160m. A different one, quiet.
-Brian N9ADG




________________________________
 From: Matthew Zilmer <[hidden email]>
To: john petters <[hidden email]>; "[hidden email]" <[hidden email]>
Sent: Thursday, December 13, 2012 9:53 AM
Subject: Re: [Elecraft] KUSB Noise Query - K3
 
USB uses differential signaling.  Your problem may not be conductive noise, but instead it could be radiated directly from the adapter, where the ferrite won't help.

KeySpan makes a USB - serial adapter that is pretty much noise-free.  Its model  is HS19, I think.

Matt Zilmer
Consultant - Product Management Dept.
Magellan Navigation / MiTAC Digital Corp.
Tel: [phone]
Cell: [phone]
In status quo voluntas non sufficit


-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of john petters
Sent: Thursday, December 13, 2012 9:25 AM
To: [hidden email]
Subject: [Elecraft] KUSB Noise Query - K3

Hi Folks,
I posted a query about K3 Serial ports a few months back - we could not get the K3 to work properly with the RS232 connection. It turned out to be a fault with the sound card, which took out the serial connections.
When I first built the K3, I bought a cheap Prolific USB converter, which radiates awful noise over the spectrum. I decided to bite the bullet and buy the proper lead, which arrived today.

Using my Toshiba laptop, on battery power, I get a couple of s points of noise on 10M with the KUSB connected and HRD fired up. This is using my
2 element DJ4VM quad, which is fed with 300 ohm twin into the shack, i.e. near the laptop.

On LF, I can hear the pulsing information, in sympathy with the flashing LEDs on the KUSB on 160M at quite a high level. I can even detect this when fed into a Marconi dummy load. The K3 and the tuning units are bonder to an RF earth - a copper stake about 8 feet away from the K3.

I have tried choking the USB lead at the laptop end, which does reduce the noise to a degree.

The question I have is - am I being unrealistic in expecting zero noise to be radiated from these adaptors?
Does anyone else have this problem - or has anyone looked for it?

It is not very noticeable on CW or SSB. To hear it best, listen in the AM mode with the AGC off. On SSB it sounds like band noise.

Is this a problem JUST with USB adaptors or can I expect silence when connecting a computer via RS232 to RS232.

If not we are sacrificing a low noise floor for the convenience of computer control.

Any views appreciated,

73




--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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[Scott Monks]

    Try "disconnecting" the K3 from the program without touching anything else.  I recently discovered that if I "disconnect" my logging program (so it is not directly controlling my K3) it will reduce noise level on 15m, about half, making weak signals very readable.  When I opened the communication and control with the program the noise came back--noise or no as I activated or dis-activated the control function. 

    I am not experienced enough with this type of control to pinpoint the real source of the noise or yet how to control it, but it is there.


However, it is frustrating for me because now I can hear them but my signal is too weak to work them!!  hi, hi

Scott

>________________________________
> From: Brian Moran <[hidden email]>
>To: Matthew Zilmer <[hidden email]>; john petters <[hidden email]>; "[hidden email]" <[hidden email]>
>Sent: Thursday, December 13, 2012 12:10 PM
>Subject: Re: [Elecraft] KUSB Noise Query - K3
>
>You may try a different K-USB. I have a K-USB that radiated terrible noise on 160m. A different one, quiet.
>-Brian N9ADG
>
>
>
>
>________________________________
>From: Matthew Zilmer <[hidden email]>
>To: john petters <[hidden email]>; "[hidden email]" <[hidden email]>
>Sent: Thursday, December 13, 2012 9:53 AM
>Subject: Re: [Elecraft] KUSB Noise Query - K3
>
>USB uses differential signaling.  Your problem may not be conductive noise, but instead it could be radiated directly from the adapter, where the ferrite won't help.
>
>KeySpan makes a USB - serial adapter that is pretty much noise-free.  Its model  is HS19, I think.
>
>Matt Zilmer
>Consultant - Product Management Dept.
>Magellan Navigation / MiTAC Digital Corp.
>Tel: [phone]
>Cell: [phone]
>In status quo voluntas non sufficit
>
>
>-----Original Message-----
>From: [hidden email] [mailto:[hidden email]] On Behalf Of john petters
>Sent: Thursday, December 13, 2012 9:25 AM
>To: [hidden email]
>Subject: [Elecraft] KUSB Noise Query - K3
>
>Hi Folks,
>I posted a query about K3 Serial ports a few months back - we could not get the K3 to work properly with the RS232 connection. It turned out to be a fault with the sound card, which took out the serial connections.
>When I first built the K3, I bought a cheap Prolific USB converter, which radiates awful noise over the spectrum. I decided to bite the bullet and buy the proper lead, which arrived today.
>
>Using my Toshiba laptop, on battery power, I get a couple of s points of noise on 10M with the KUSB connected and HRD fired up. This is using my
>2 element DJ4VM quad, which is fed with 300 ohm twin into the shack, i.e. near the laptop.
>
>On LF, I can hear the pulsing information, in sympathy with the flashing LEDs on the KUSB on 160M at quite a high level. I can even detect this when fed into a Marconi dummy load. The K3 and the tuning units are bonder to an RF earth - a copper stake about 8 feet away from the K3.
>
>I have tried choking the USB lead at the laptop end, which does reduce the noise to a degree.
>
>The question I have is - am I being unrealistic in expecting zero noise to be radiated from these adaptors?
>Does anyone else have this problem - or has anyone looked for it?
>
>It is not very noticeable on CW or SSB. To hear it best, listen in the AM mode with the AGC off. On SSB it sounds like band noise.
>
>Is this a problem JUST with USB adaptors or can I expect silence when connecting a computer via RS232 to RS232.
>
>If not we are sacrificing a low noise floor for the convenience of computer control.
>
>Any views appreciated,
>
>73
>
>
>
>
>--
>John Petters
>www.traditional-jazz.com
>Amateur Radio Station G3YPZ
>______________________________________________________________
>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
>______________________________________________________________
>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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>
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>Please help support this email list: http://www.qsl.net/donate.html
>
>
>

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[john petters]

Matt & Brian, thanks for the suggestions. This KUSB is the latest type,
I believe with the  FTDI chip set.. The old one I had was a Prolific
chip set - but not a KUSB.
I'll look up the HS19.
73
John

On 13/12/2012 18:10, Brian Moran wrote:

> You may try a different K-USB. I have a K-USB that radiated terrible
> noise on 160m. A different one, quiet.
> -Brian N9ADG
>
>
> ------------------------------------------------------------------------
> *From:* Matthew Zilmer <[hidden email]>
> *To:* john petters <[hidden email]>;
> "[hidden email]" <[hidden email]>
> *Sent:* Thursday, December 13, 2012 9:53 AM
> *Subject:* Re: [Elecraft] KUSB Noise Query - K3
>
> USB uses differential signaling.  Your problem may not be conductive
> noise, but instead it could be radiated directly from the adapter, where
> the ferrite won't help.
>
> KeySpan makes a USB - serial adapter that is pretty much noise-free.
> Its model  is HS19, I think.
>
> Matt Zilmer
> Consultant - Product Management Dept.
> Magellan Navigation / MiTAC Digital Corp.
> Tel: [phone]
> Cell: [phone]
> In status quo voluntas non sufficit
>
>
> -----Original Message-----
> From: [hidden email]
> <mailto:[hidden email]>
> [mailto:[hidden email]
> <mailto:[hidden email]>] On Behalf Of john petters
> Sent: Thursday, December 13, 2012 9:25 AM
> To: [hidden email] <mailto:[hidden email]>
> Subject: [Elecraft] KUSB Noise Query - K3
>
> Hi Folks,
> I posted a query about K3 Serial ports a few months back - we could not
> get the K3 to work properly with the RS232 connection. It turned out to
> be a fault with the sound card, which took out the serial connections.
> When I first built the K3, I bought a cheap Prolific USB converter,
> which radiates awful noise over the spectrum. I decided to bite the
> bullet and buy the proper lead, which arrived today.
>
> Using my Toshiba laptop, on battery power, I get a couple of s points of
> noise on 10M with the KUSB connected and HRD fired up. This is using my
> 2 element DJ4VM quad, which is fed with 300 ohm twin into the shack,
> i.e. near the laptop.
>
> On LF, I can hear the pulsing information, in sympathy with the flashing
> LEDs on the KUSB on 160M at quite a high level. I can even detect this
> when fed into a Marconi dummy load. The K3 and the tuning units are
> bonder to an RF earth - a copper stake about 8 feet away from the K3.
>
> I have tried choking the USB lead at the laptop end, which does reduce
> the noise to a degree.
>
> The question I have is - am I being unrealistic in expecting zero noise
> to be radiated from these adaptors?
> Does anyone else have this problem - or has anyone looked for it?
>
> It is not very noticeable on CW or SSB. To hear it best, listen in the
> AM mode with the AGC off. On SSB it sounds like band noise.
>
> Is this a problem JUST with USB adaptors or can I expect silence when
> connecting a computer via RS232 to RS232.
>
> If not we are sacrificing a low noise floor for the convenience of
> computer control.
>
> Any views appreciated,
>
> 73
>
>
>
>
> --
> John Petters
> www.traditional-jazz.com <http://www.traditional-jazz.com/>
> Amateur Radio Station G3YPZ
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email] <mailto:[hidden email]>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email] <mailto:[hidden email]>
>
> This list hosted by: http://www.qsl.net <http://www.qsl.net/>
> Please help support this email list: http://www.qsl.net/donate.html
>
>

--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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[Buck - k4ia]

I have found that I must be sure to screw in (not just plug in)  the
serial connector on the back of the K3.  If I don't, I will hear a
pulsed rushing noise from the USB.


Buck
k4ia

On 12/13/2012 12:53 PM, Matthew Zilmer wrote:

> USB uses differential signaling.  Your problem may not be conductive noise, but instead it could be radiated directly from the adapter, where the ferrite won't help.
>
> KeySpan makes a USB - serial adapter that is pretty much noise-free.  Its model  is HS19, I think.
>
> Matt Zilmer
> Consultant - Product Management Dept.
> Magellan Navigation / MiTAC Digital Corp.
> Tel: [phone]
> Cell: [phone]
> In status quo voluntas non sufficit
>
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]] On Behalf Of john petters
> Sent: Thursday, December 13, 2012 9:25 AM
> To: [hidden email]
> Subject: [Elecraft] KUSB Noise Query - K3
>
> Hi Folks,
> I posted a query about K3 Serial ports a few months back - we could not get the K3 to work properly with the RS232 connection. It turned out to be a fault with the sound card, which took out the serial connections.
> When I first built the K3, I bought a cheap Prolific USB converter, which radiates awful noise over the spectrum. I decided to bite the bullet and buy the proper lead, which arrived today.
>
> Using my Toshiba laptop, on battery power, I get a couple of s points of noise on 10M with the KUSB connected and HRD fired up. This is using my
> 2 element DJ4VM quad, which is fed with 300 ohm twin into the shack, i.e. near the laptop.
>
> On LF, I can hear the pulsing information, in sympathy with the flashing LEDs on the KUSB on 160M at quite a high level. I can even detect this when fed into a Marconi dummy load. The K3 and the tuning units are bonder to an RF earth - a copper stake about 8 feet away from the K3.
>
> I have tried choking the USB lead at the laptop end, which does reduce the noise to a degree.
>
> The question I have is - am I being unrealistic in expecting zero noise to be radiated from these adaptors?
> Does anyone else have this problem - or has anyone looked for it?
>
> It is not very noticeable on CW or SSB. To hear it best, listen in the AM mode with the AGC off. On SSB it sounds like band noise.
>
> Is this a problem JUST with USB adaptors or can I expect silence when connecting a computer via RS232 to RS232.
>
> If not we are sacrificing a low noise floor for the convenience of computer control.
>
> Any views appreciated,
>
> 73
>
>
>
>
> --
> John Petters
> www.traditional-jazz.com
> Amateur Radio Station G3YPZ
> ______________________________________________________________
> 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
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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[john petters]

I've done that, Buck, still noisy. Many Thanks,
73,
John

On 13/12/2012 21:57, Buck - k4ia wrote:

> I have found that I must be sure to screw in (not just plug in)  the
> serial connector on the back of the K3.  If I don't, I will hear a
> pulsed rushing noise from the USB.
>
>
> Buck
> k4ia
>
> On 12/13/2012 12:53 PM, Matthew Zilmer wrote:
>> USB uses differential signaling.  Your problem may not be conductive
>> noise, but instead it could be radiated directly from the adapter,
>> where the ferrite won't help.
>>
>> KeySpan makes a USB - serial adapter that is pretty much noise-free.
>> Its model  is HS19, I think.
>>
>> Matt Zilmer
>> Consultant - Product Management Dept.
>> Magellan Navigation / MiTAC Digital Corp.
>> Tel: [phone]
>> Cell: [phone]
>> In status quo voluntas non sufficit
>>
>>
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]] On Behalf Of john petters
>> Sent: Thursday, December 13, 2012 9:25 AM
>> To: [hidden email]
>> Subject: [Elecraft] KUSB Noise Query - K3
>>
>> Hi Folks,
>> I posted a query about K3 Serial ports a few months back - we could
>> not get the K3 to work properly with the RS232 connection. It turned
>> out to be a fault with the sound card, which took out the serial
>> connections.
>> When I first built the K3, I bought a cheap Prolific USB converter,
>> which radiates awful noise over the spectrum. I decided to bite the
>> bullet and buy the proper lead, which arrived today.
>>
>> Using my Toshiba laptop, on battery power, I get a couple of s points
>> of noise on 10M with the KUSB connected and HRD fired up. This is
>> using my
>> 2 element DJ4VM quad, which is fed with 300 ohm twin into the shack,
>> i.e. near the laptop.
>>
>> On LF, I can hear the pulsing information, in sympathy with the
>> flashing LEDs on the KUSB on 160M at quite a high level. I can even
>> detect this when fed into a Marconi dummy load. The K3 and the tuning
>> units are bonder to an RF earth - a copper stake about 8 feet away
>> from the K3.
>>
>> I have tried choking the USB lead at the laptop end, which does reduce
>> the noise to a degree.
>>
>> The question I have is - am I being unrealistic in expecting zero
>> noise to be radiated from these adaptors?
>> Does anyone else have this problem - or has anyone looked for it?
>>
>> It is not very noticeable on CW or SSB. To hear it best, listen in the
>> AM mode with the AGC off. On SSB it sounds like band noise.
>>
>> Is this a problem JUST with USB adaptors or can I expect silence when
>> connecting a computer via RS232 to RS232.
>>
>> If not we are sacrificing a low noise floor for the convenience of
>> computer control.
>>
>> Any views appreciated,
>>
>> 73
>>
>>
>>
>>
>> --
>> John Petters
>> www.traditional-jazz.com
>> Amateur Radio Station G3YPZ
>> ______________________________________________________________
>> 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
>> ______________________________________________________________
>> 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
>
> ______________________________________________________________
> 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
>

--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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[Mike Harris]

A few years ago I was receiving noise from my PC on 6M, via the serial
interface cable.  I was also receiving it when using the KUSB of the
time with the Prolific chip-set.

I made a new serial cable using CAT-6 and the technique used in the
"K9YC RFI-Ham.pdf" tutorial, page 38.

This significantly reduce the noise and interestingly when I placed it
in series with the KUSB it had the same effect.  My new serial cable was
about 3 metres long and I was going to make up a short version to see if
it had the same effect.  Unfortunately I never did.

Regards,

Mike VP8NO

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[john petters]

Thanks Mike.
Interesting article.
73
John


On 13/12/2012 22:52, Mike Harris wrote:

> A few years ago I was receiving noise from my PC on 6M, via the serial
> interface cable.  I was also receiving it when using the KUSB of the
> time with the Prolific chip-set.
>
> I made a new serial cable using CAT-6 and the technique used in the
> "K9YC RFI-Ham.pdf" tutorial, page 38.
>
> This significantly reduce the noise and interestingly when I placed it
> in series with the KUSB it had the same effect.  My new serial cable was
> about 3 metres long and I was going to make up a short version to see if
> it had the same effect.  Unfortunately I never did.
>
> Regards,
>
> Mike VP8NO
>
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--
John Petters
www.traditional-jazz.com
Amateur Radio Station G3YPZ
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