Topband: Digital mode spurious issues
KB8NTY
kb8nty at wowway.com
Tue Dec 31 15:27:52 EST 2013
----- Original Message -----
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Sent: Tuesday, December 31, 2013 12:00 PM
Subject: Topband Digest, Vol 132, Issue 30
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My Kenwood TS-590S "NR" and A-notch "BC" controls when properly adjusted
perform magic with this scenario!
*Happy New Year*
KB8NTY
http://www.rossradio.net/
****************************************************
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Topband digest..."
>
>
> Today's Topics:
>
> 1. Digital mode spurious issues (Tom W8JI)
> 2. Re: Digital mode spurious issues (Mike Waters)
> 3. Re: Digital mode spurious issues (Jim Brown)
> 4. Re: Digital mode spurious issues (Richard (Rick) Karlquist)
> 5. Re: Digital mode spurious issues (Joe Subich, W4TV)
> 6. Re: Digital mode spurious issues (Charlie Cunningham)
> 7. Re: Digital mode spurious issues (Jim Brown)
> 8. Re: [CQ-Contest] Stew Perry Streaming Audio (Herb Schoenbohm)
> 9. Re: Digital mode spurious issues (Grant Saviers)
> 10. Re: Digital mode spurious issues (W2RU - Bud Hippisley)
> 11. Re: Digital mode spurious issues (Mike Waters)
> 12. Re: Digital mode spurious issues (Charlie Cunningham)
> 13. Re: Digital mode spurious issues (JC N4IS)
> 14. Re: Digital mode spurious issues (Mike Waters)
> 15. Re: Digital mode spurious issues (Tom W8JI)
> 16. Re: Digital mode spurious issues (Charlie Cunningham)
> 17. Re: Digital mode spurious issues (Steven Raas)
> 18. Re: Digital mode spurious issues (Mike Waters)
> 19. Re: Stew Perry Streaming Audio (Shoppa, Tim)
> 20. CA/OR/AZ activity during Stew Perry - anecdotal data (Barry N1EU)
> 21. Re: Digital mode spurious issues (Tom W8JI)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 30 Dec 2013 12:11:49 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: "Topband" <topband at contesting.com>
> Subject: Topband: Digital mode spurious issues
> Message-ID: <AB0B5258E3B345428ADE0FAFD65179C0 at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=response
>
> I have not been on the air for a year or so, but decided to get back on. I
> was listening to a DX station around 1833 when a digimode station up
> roughly
> around 1837 came on with a LSB "spurious" signal on 1833. His signal was a
> series of slowly changing stepped tones. I don't know what mode that was.
> His unwanted sideband suppression was about 40 dB, but that was not nearly
> enough. He was 15 dB out of noise with his unwanted sideband.
>
> Does anyone know of a universal software to decode signals? Since the FCC
> does not require a CW ID, I think that is the only way to identify
> stations.
>
> I assume:
>
> 1.) Operators are unlikely to accept they have a problem if they are
> getting
> good reports on the intentional signal
>
> 2.) Some rigs just should not be used for digimodes (this was a sideband
> suppression issue)
>
> 3.) Those who unwisely placed digimode subbands next to popular weak
> signal
> areas, especially when sideband selection produces a supurious that falls
> in
> weak signal areas, are unlikely to rethink the poor placement or poor
> advice
> on selecting sidebands
>
> 4.) With a little work to convince them, most digital ops with radio
> problems would avoid operating
>
> 73 Tom
>
>
>
> ------------------------------
>
> Message: 2
> Date: Mon, 30 Dec 2013 12:30:34 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: Tom W8JI <w8ji at w8ji.com>
> Cc: Topband <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <CA+FxYXj7jeqKdTtR1BWSWZU-ZjsC0h79YN8HhjDfJKs+xLzQPA at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Tom,
>
> I believe the mode that operates at 1873-1838 is JT65, and WSJT is needed
> to decode it. I never tried it. It was developed by K1JT for weak-signal
> and EME work.
> http://www.physics.princeton.edu/pulsar/K1JT/wsjt.html
>
> A common scenario with digital modes is that the audio into the mic input
> is too high, causing unwanted spurs.
>
> 73, Mike
> www.w0btu.com
>
>
> On Mon, Dec 30, 2013 at 11:11 AM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>> ... a digimode station up roughly around 1837 came on with a LSB
>> "spurious" signal on 1833. His signal was a series of slowly changing
>> stepped tones. I don't know what mode that was. His unwanted sideband
>> suppression was about 40 dB, but that was not nearly enough. He was 15 dB
>> out of noise with his unwanted sideband.
>>
>> Does anyone know of a universal software to decode signals? Since the FCC
>> does not require a CW ID, I think that is the only way to identify
>> stations. ...
>>
>
>
> ------------------------------
>
> Message: 3
> Date: Mon, 30 Dec 2013 14:17:57 -0800
> From: Jim Brown <jim at audiosystemsgroup.com>
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <52C1F115.6050304 at audiosystemsgroup.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> You're both right -- it is either JT65 or JT9. WSJT software, based on
> protocols developed by K1JT, will decode both modes. Another software
> package called JT65-HF will decode only JT65.
>
> And yes, the trash Tom was hearing was either overdriven audio or a
> crummy radio or both. Some of the newer hams using these modes are also
> using pretty crummy radios -- all-banders in the $900 price range. OTOH,
> most are running flea power -- 20W is QRO for this crowd.
>
> I've done a fair amount of JT65, mostly on 6M and 160M, using my K3.
> I've also used other K1JT modes designed for meteor scatter (FSK441) and
> ionospheric scatter (SCAT). JT9 is Joe's latest and greatest protocol,
> requiring a fraction of the bandwidth of JT65.
>
> 73, Jim K9YC
>
> On 12/30/2013 10:30 AM, Mike Waters wrote:
>> I believe the mode that operates at 1873-1838 is JT65, and WSJT is needed
>> to decode it. I never tried it. It was developed by K1JT for weak-signal
>> and EME work.
>> http://www.physics.princeton.edu/pulsar/K1JT/wsjt.html
>>
>> A common scenario with digital modes is that the audio into the mic input
>> is too high, causing unwanted spurs.
>
>
>
> ------------------------------
>
> Message: 4
> Date: Mon, 30 Dec 2013 14:59:13 -0800
> From: "Richard (Rick) Karlquist" <richard at karlquist.com>
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <52C1FAC1.2000809 at karlquist.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> The simplest technical solution would be for the
> digital mode users to put the radio in LSB mode.
> This puts unwanted sideband QRM away from the
> DX CW window. Does the Joe Taylor software have
> a provision for this?
>
> Rick N6RK
>
>
> ------------------------------
>
> Message: 5
> Date: Mon, 30 Dec 2013 18:05:12 -0500
> From: "Joe Subich, W4TV" <lists at subich.com>
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <52C1FC28.60806 at subich.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>
> > Does the Joe Taylor software have a provision for this?
>
> No, Joe Taylor's protocols are not capable of operating in LSB.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 12/30/2013 5:59 PM, Richard (Rick) Karlquist wrote:
>> The simplest technical solution would be for the
>> digital mode users to put the radio in LSB mode.
>> This puts unwanted sideband QRM away from the
>> DX CW window. Does the Joe Taylor software have
>> a provision for this?
>>
>> Rick N6RK
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
> ------------------------------
>
> Message: 6
> Date: Mon, 30 Dec 2013 18:13:47 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Joe Subich, W4TV'" <lists at subich.com>, <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAABg31XzAMKNCvuYjy/t7uksBAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> I would think that IMD products in a high-level PA that is over-driven
> beyond good linearity limits could add some junk in the "undesired
> sideband"? FWIW
>
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Joe
> Subich, W4TV
> Sent: Monday, December 30, 2013 6:05 PM
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
>
>
> > Does the Joe Taylor software have a provision for this?
>
> No, Joe Taylor's protocols are not capable of operating in LSB.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 12/30/2013 5:59 PM, Richard (Rick) Karlquist wrote:
>> The simplest technical solution would be for the digital mode users to
>> put the radio in LSB mode.
>> This puts unwanted sideband QRM away from the DX CW window. Does the
>> Joe Taylor software have a provision for this?
>>
>> Rick N6RK
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 7
> Date: Mon, 30 Dec 2013 15:51:38 -0800
> From: Jim Brown <jim at audiosystemsgroup.com>
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <52C2070A.40705 at audiosystemsgroup.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 12/30/2013 3:13 PM, Charlie Cunningham wrote:
>> I would think that IMD products in a high-level PA that is over-driven
>> beyond good linearity limits could add some junk in the "undesired
>> sideband"? FWIW
>
> Yes. Indeed, any IMD would do that. K6XX is an Elecraft engineer who
> worked on their KPA500, among other things, and looked at a lot of
> competing power amps in preparation for doing so. Bob recently did an
> excellent tutorial presentation to a meeting of the Northern California
> Contest Club about the root causes of sideband trash, the general
> properties of various amplifier types, and how to minimize the trash.
>
> In general:
>
> Distortion products increase when the antenna is poorly matched to the
> amplifier That's true whether it's a tuned tube amp or a fixed tuned
> solid state amp -- in other words, the tube amp must be carefully tuned,
> and the solid state amp should be used with a tuner if the antenna is
> not an ideal match.
>
> Distortion products increase as power supply voltage decreases. In other
> words, a rig designed to run on 13.8 volts will be much cleaner at 13.8
> volts than at 12V.
>
> Most solid state output stages are cleaner at half power than at full
> power. That means that a rig will be cleaner driving a power amp at 50W
> than at 100 W.
>
> Using AGC between the power amp and the rig to set output level is a
> recipe for sideband trash.
>
> A properly tuned hollow state power amp is typically 8-10 dB cleaner
> than the best solid state amps.
>
> Fast rise time of the keying waveform is the major cause of clicks W8JI
> and others long ago identified this as the cause of the FT1000-series
> rigs awful clicks, and fixed them. The rise time of some rigs (notably
> the IC7600) is adjustable, and only the slowest rise time is acceptable.
> The K3 uses an optimally shaped keying waveform (which designer N6KR
> calls "sigmoidal") to minimize clicks, and it is not user adjustable.
>
> Most ICOM rigs have overshoot that also causes clicks.
>
> Something I learned from N6KR a few days ago is that the very low level
> of sideband trash from a K3 is the result of two design elements. First,
> the synthesizer is very clean.. Second, they run it through the TX
> crystal filter, which gets rid of trash more distant from the carrier.
>
> 73, Jim K9YC
>
>
> ------------------------------
>
> Message: 8
> Date: Mon, 30 Dec 2013 20:39:45 -0400
> From: Herb Schoenbohm <herbs at vitelcom.net>
> To: topband at contesting.com
> Subject: Re: Topband: [CQ-Contest] Stew Perry Streaming Audio
> Message-ID: <52C21251.6010200 at vitelcom.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> This is just not possible anymore and there are so many situations like
> Greg experiences where the only hope to hear anything is by employing
> new technology. Also the 100KM rule, if there is such a rule, is
> intriguing because a remote RX in the BVI (a different DXCC country)
> would really be nice now that I have a new ham a few blocks away running
> a CQ machine during the contest in the DX window for the duration of the
> contest. Problems such as this along with high urban QRN are much more
> common and solution will be found. To arbitrarily block new innovations
> and technology to solve some of these issues is to me not going in the
> right direction. I think a better approach would be to allow for
> different categories creating incentives for inovations, rather than
> just outright ban them.
>
>
> Herb Schoenbohm, KV4FZ
>
>
>
>
> On 12/28/2013 4:19 PM, Greg - ZL3IX wrote:
>> "enjoy the contest the way we did back when Stew Perry was around"
>
>
>
> ------------------------------
>
> Message: 9
> Date: Mon, 30 Dec 2013 17:12:10 -0800
> From: Grant Saviers <grants2 at pacbell.net>
> To: Tom W8JI <w8ji at w8ji.com>, Topband <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <52C219EA.6040106 at pacbell.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> The SignaLink supported software page has a nice summary of software
> decoders see http://www.tigertronics.com/sl_soft.htm
>
> If "universal" means automatic selection of the correct decoding mode,
> that would be a challenge!
>
> Grant KZ1W
>
> On 12/30/2013 9:11 AM, Tom W8JI wrote:
>> I have not been on the air for a year or so, but decided to get back
>> on. I was listening to a DX station around 1833 when a digimode
>> station up roughly around 1837 came on with a LSB "spurious" signal on
>> 1833. His signal was a series of slowly changing stepped tones. I
>> don't know what mode that was. His unwanted sideband suppression was
>> about 40 dB, but that was not nearly enough. He was 15 dB out of noise
>> with his unwanted sideband.
>>
>> Does anyone know of a universal software to decode signals? Since the
>> FCC does not require a CW ID, I think that is the only way to identify
>> stations.
>>
>> I assume:
>>
>> 1.) Operators are unlikely to accept they have a problem if they are
>> getting good reports on the intentional signal
>>
>> 2.) Some rigs just should not be used for digimodes (this was a
>> sideband suppression issue)
>>
>> 3.) Those who unwisely placed digimode subbands next to popular weak
>> signal areas, especially when sideband selection produces a supurious
>> that falls in weak signal areas, are unlikely to rethink the poor
>> placement or poor advice on selecting sidebands
>>
>> 4.) With a little work to convince them, most digital ops with radio
>> problems would avoid operating
>>
>> 73 Tom
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
>
> ------------------------------
>
> Message: 10
> Date: Mon, 30 Dec 2013 20:32:37 -0500
> From: W2RU - Bud Hippisley <W2RU at frontiernet.net>
> To: jim at audiosystemsgroup.com
> Cc: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <656317B8-1858-42F1-9FFD-23DDE17534A6 at frontiernet.net>
> Content-Type: text/plain; charset=us-ascii
>
> This is a little off-topic relative to the Subject line, but extremely
> relevant to enjoyable Topband operating:
>
> On Dec 30, 2013, at 6:51 38PM, Jim Brown <jim at audiosystemsgroup.com>
> wrote:
>
>> Fast rise time of the keying waveform is the major cause of clicks. W8JI
>> and others long ago identified this as the cause of the FT1000-series
>> rigs awful clicks, and fixed them. The rise time of some rigs (notably
>> the IC7600) is adjustable, and only the slowest rise time is acceptable.
>
> Add the venerable Kenwood TS-950SDX to the list of rigs with
> user-adjustable rise/fall times. And -- as Jim notes -- only the slowest
> rise time is fully acceptable, despite the pains Kenwood took to carefully
> "shape" those RF waveforms during their "on" and "off" transition periods.
>
> In the case of the 950SDX, the user can select nominal rise/fall times
> labeled 2, 4, 6, or 8 milliseconds (ms) from one of the configuration
> menus accessible via the front panel MENU options. A few years back, in
> extensive tests on a daytime 80-m band with an equally fanatical friend
> listening critically, we determined that -only- the 8-ms setting was
> "clean" with respect to click generation. Probably the 6-ms setting would
> be marginally "OK" if the transmitted signal were not loud anywhere, but
> since my usual objective when chasing DX on 160 is to be as loud as I can,
> 6 ms is not really an acceptable solution for maintaining good relations
> with my close-in Topband "neighbors" here on the east coast of North
> America. Once we ran those tests, I set the TS-950SDX menu choice to 8
> ms, and I've not changed it since.
>
> Bud, W2RU
>
>
>
>
> ------------------------------
>
> Message: 11
> Date: Mon, 30 Dec 2013 20:12:33 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: topband <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <CA+FxYXiRKZnGLMKGdN1aTsFzBFkrGdY03znWG59EtadKSmF+jQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> You are right. There is no universal software that can do that. But I used
> to code software, and I'm convinced that the status quo in amateur digital
> software can be greatly improved. See
> http://www.eham.net/ehamforum/smf/index.php?topic=80740.0 .
>
> If anyone wants to take up where we left off on that eHam thread, then
> let's take the discussion there.
>
> 73, Mike
> www.w0btu.com
>
> On Mon, Dec 30, 2013 at 7:12 PM, Grant Saviers <grants2 at pacbell.net>
> wrote:
>
>>
>> If "universal" means automatic selection of the correct decoding mode,
>> that would be a challenge!
>>
>
>
> ------------------------------
>
> Message: 12
> Date: Mon, 30 Dec 2013 21:34:26 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: <jim at audiosystemsgroup.com>, <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAAJjC6JAJz/RMjAuEvO+ytjsBAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> Hi, Jim
>
> Well as one who has been an RF and radio engineer and designer for 40+
> years, I have to agree with most all of your points. Great deal of truth
> in
> there, but so many guys don't appreciate all those things and their
> inclination is "crank it to the right" and "the "louder you shout, the
> further you get"! And they are looking for large meter excursions. To
> appreciate the tendency to overdrive transmitters and amplifiers. One need
> only listen to the the prevalence of awful key clicks and SSB splatter in
> contests!
>
> (And "real men" use vacuum tubes to develop "real power"! :-) )
>
> 73,
> Charie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Jim
> Brown
> Sent: Monday, December 30, 2013 6:52 PM
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
>
> On 12/30/2013 3:13 PM, Charlie Cunningham wrote:
>> I would think that IMD products in a high-level PA that is over-driven
>> beyond good linearity limits could add some junk in the "undesired
>> sideband"? FWIW
>
> Yes. Indeed, any IMD would do that. K6XX is an Elecraft engineer who
> worked on their KPA500, among other things, and looked at a lot of
> competing power amps in preparation for doing so. Bob recently did an
> excellent tutorial presentation to a meeting of the Northern California
> Contest Club about the root causes of sideband trash, the general
> properties of various amplifier types, and how to minimize the trash.
>
> In general:
>
> Distortion products increase when the antenna is poorly matched to the
> amplifier That's true whether it's a tuned tube amp or a fixed tuned
> solid state amp -- in other words, the tube amp must be carefully tuned,
> and the solid state amp should be used with a tuner if the antenna is
> not an ideal match.
>
> Distortion products increase as power supply voltage decreases. In other
> words, a rig designed to run on 13.8 volts will be much cleaner at 13.8
> volts than at 12V.
>
> Most solid state output stages are cleaner at half power than at full
> power. That means that a rig will be cleaner driving a power amp at 50W
> than at 100 W.
>
> Using AGC between the power amp and the rig to set output level is a
> recipe for sideband trash.
>
> A properly tuned hollow state power amp is typically 8-10 dB cleaner
> than the best solid state amps.
>
> Fast rise time of the keying waveform is the major cause of clicks W8JI
> and others long ago identified this as the cause of the FT1000-series
> rigs awful clicks, and fixed them. The rise time of some rigs (notably
> the IC7600) is adjustable, and only the slowest rise time is acceptable.
> The K3 uses an optimally shaped keying waveform (which designer N6KR
> calls "sigmoidal") to minimize clicks, and it is not user adjustable.
>
> Most ICOM rigs have overshoot that also causes clicks.
>
> Something I learned from N6KR a few days ago is that the very low level
> of sideband trash from a K3 is the result of two design elements. First,
> the synthesizer is very clean.. Second, they run it through the TX
> crystal filter, which gets rid of trash more distant from the carrier.
>
> 73, Jim K9YC
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 13
> Date: Mon, 30 Dec 2013 21:50:47 -0500
> From: "JC N4IS" <n4is at comcast.net>
> To: "'Mike Waters'" <mikewate at gmail.com>, "'Tom W8JI'" <w8ji at w8ji.com>
> Cc: 'Topband' <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <005801cf05d3$1bd5f9c0$5381ed40$@comcast.net>
> Content-Type: text/plain; charset="us-ascii"
>
> Tom, Mike is right, the issue with audio overload is complex for most of
> new radios, most of them have A/D just at the MIC input, if the A/D
> overloads the RF chain is compromised. These radios have no actual
> filters,
> everything is digital, like the IC7600. An analog radio is BW limited by
> the
> SSB crystal filter but SDR don't, when the A/D overloads, there are
> spoors
> everywhere several KHz far from the carrier; enough to trash the entire
> band.
>
> Using a SDR water fall it is easy to see the signal transitions and
> associate the trash with the main signal. I've seen several spoors every
> 10
> KHz almost 100KHz up and down 1838. This is a growing problem.
>
> 73, JC
> N4IS
>
>
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Mike
> Waters
> Sent: Monday, December 30, 2013 1:31 PM
> To: Tom W8JI
> Cc: Topband
> Subject: Re: Topband: Digital mode spurious issues
>
> Tom,
>
> I believe the mode that operates at 1873-1838 is JT65, and WSJT is needed
> to
> decode it. I never tried it. It was developed by K1JT for weak-signal and
> EME work.
> http://www.physics.princeton.edu/pulsar/K1JT/wsjt.html
>
> A common scenario with digital modes is that the audio into the mic input
> is
> too high, causing unwanted spurs.
>
> 73, Mike
> www.w0btu.com
>
>
> On Mon, Dec 30, 2013 at 11:11 AM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>> ... a digimode station up roughly around 1837 came on with a LSB
>> "spurious" signal on 1833. His signal was a series of slowly changing
>> stepped tones. I don't know what mode that was. His unwanted sideband
>> suppression was about 40 dB, but that was not nearly enough. He was 15
>> dB out of noise with his unwanted sideband.
>>
>> Does anyone know of a universal software to decode signals? Since the
>> FCC does not require a CW ID, I think that is the only way to identify
>> stations. ...
>>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 14
> Date: Mon, 30 Dec 2013 21:17:28 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: topband <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <CA+FxYXikYNQqzEAf+rHdJkNG1ztop1_V3UbBiTauLsRzpMqQ_g at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Bingo! The waterfall display was a wonderful invention, wasn't it? And I
> don't even use SDR. (Yet.)
>
> When I used to operate PSK31, I adjusted the audio levels with my own
> signal displayed on the waterfall, and so it was easy to see when the
> input
> from the sound card was too high. The spurs from AF overload are very easy
> to see on the waterfall.
>
> 73, Mike
> www.w0btu.com
>
> On Mon, Dec 30, 2013 at 8:50 PM, JC N4IS <n4is at comcast.net> wrote:
>
>>
>> Using a SDR water fall it is easy to see the signal transitions and
>> associate the trash with the main signal. I've seen several spoors every
>> 10
>> KHz almost 100KHz up and down 1838. This is a growing problem.
>>
>
>
> ------------------------------
>
> Message: 15
> Date: Mon, 30 Dec 2013 22:55:46 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <11A6F15D3D9F452F83930E7A3EBDA10F at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
> Thanks everyone for the suggestions. I'm going to have to install some
> software to identify some of the signals.
>
>
>>I would think that IMD products in a high-level PA that is over-driven
>> beyond good linearity limits could add some junk in the "undesired
>> sideband"? FWIW
>>
>
> IMD **requires** two or more signals at once, and does not appear anything
> like sideband leakage. This was a single shifting tone, and the lower
> frequency signal went the opposite way but the same amount as the main
> signal with shifts. That is classic for inadequate sideband suppression.
>
> There are multiple problems with using SSB to transmit audio tones and
> "thinking" it is a pure digi mode.
>
> 1.) things like this do not show on almost all digi waterfalls because
> they
> are out of passband of the other fellows receiver.
>
> 2.) SSB carrier, noise, and opposite sideband suppression is limited by
> the
> radio quality
>
> 3.) output purity is also limited by audio input purity, which includes
> audio line issues
>
> 4.) most digi operators do not have the low noise antennas most DXers
> have,
> and cannot hear some fairly strong signals. They are often on digimodes
> because of that!
>
> 5.) radios have terrible SSB transmitter performance compared to even fair
> receivers, so the transmitters often set the adjacent channel interference
> levels
>
> Placing digimodes near weak signal areas is not very wise frequency
> planning, but there is nothing anyone can do about it.
>
>
>
> ------------------------------
>
> Message: 16
> Date: Mon, 30 Dec 2013 23:28:41 -0500
> From: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>
> To: "'Tom W8JI'" <w8ji at w8ji.com>, <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <!&!AAAAAAAAAAAYAAAAAAAAAF0xXac1rOhFkn7GlcEWNIjCgAAAEAAAABORbRe1dtFDk174Pca2TsABAAAAAA==@nc.rr.com>
>
> Content-Type: text/plain; charset="us-ascii"
>
> Well, I certainly have to agree, Tom, if the signal on the desired
> sideband
> is just a single shifting tone. Might get messier if an sudio stage or A/D
> is driven into limiting and producing harmonic distortion at audio, I
> guess.
>
> 73,
> Charlie, K4OTV
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Tom
> W8JI
> Sent: Monday, December 30, 2013 10:56 PM
> To: topband at contesting.com
> Subject: Re: Topband: Digital mode spurious issues
>
> Thanks everyone for the suggestions. I'm going to have to install some
> software to identify some of the signals.
>
>
>>I would think that IMD products in a high-level PA that is over-driven
>> beyond good linearity limits could add some junk in the "undesired
>> sideband"? FWIW
>>
>
> IMD **requires** two or more signals at once, and does not appear anything
> like sideband leakage. This was a single shifting tone, and the lower
> frequency signal went the opposite way but the same amount as the main
> signal with shifts. That is classic for inadequate sideband suppression.
>
> There are multiple problems with using SSB to transmit audio tones and
> "thinking" it is a pure digi mode.
>
> 1.) things like this do not show on almost all digi waterfalls because
> they
> are out of passband of the other fellows receiver.
>
> 2.) SSB carrier, noise, and opposite sideband suppression is limited by
> the
> radio quality
>
> 3.) output purity is also limited by audio input purity, which includes
> audio line issues
>
> 4.) most digi operators do not have the low noise antennas most DXers
> have,
> and cannot hear some fairly strong signals. They are often on digimodes
> because of that!
>
> 5.) radios have terrible SSB transmitter performance compared to even fair
> receivers, so the transmitters often set the adjacent channel interference
> levels
>
> Placing digimodes near weak signal areas is not very wise frequency
> planning, but there is nothing anyone can do about it.
>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
> ------------------------------
>
> Message: 17
> Date: Mon, 30 Dec 2013 23:29:09 -0500
> From: Steven Raas <sjraas at gmail.com>
> To: Tom W8JI <w8ji at w8ji.com>
> Cc: "topband at contesting.com" <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <CABOEzZoFoWUPJ9zD3b4t1yDjwjLaBKui8dnU1L+1eYB=0woMYw at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Tom,
>
> I would have to agree. Let me also add my personal experiences on 160m
> JT65, were good, however, at the latter stages of me being QRV on the
> band,
> I was very politely spoken to, and delightfully educated on such matters
> by
> Les, KL7J , whom really gave me some great insight on a then and still new
> band to me, for this I am ever grateful. We tried to contact on many
> occasions a few years back on 160M JT-65, however the latter attempts were
> lower in the band , 1807 ish or so if I recall. I was one of the many
> daily
> 160M ops for quite some time, but after learning, & progressing, if I was
> QRV on 160 at the moment, I would take it ( digital ops ) down the band. I
> will also admit, that I was lured with the possibility ( at those times )
> of my 1st trans-oceanic 160m QSO using JT65 ( or any mode ) , with my
> experiences now, I would say that waiting for prop, and running 4 or 5 cw
> q's was much easier for those 1st trans-oceanic q's. Not to mention that
> the long deep fades that I had ( with very very limited antennas which are
> frequently common with 160 digi mode ops ) would not be very beneficial
> for
> JT65 ' long haul / high qsb qso's, however this is not always the case. I
> can even say that to this day, I had yet to work any DX on 160m JT-65, cw
> now, is a different story thankfully :) There is also WSPR activity in
> that area of the band if I recall ( that may have changed ) amongst a few
> others. I think that progress could be made in getting the digi ops to
> qsy,
> perhaps to the lower end of the band, I'll be honest tho, I think that the
> hardest part would be getting the word out to the masses, however when
> presented with facts, and honest concern with the forsight of keeping the
> band active and everyone happy, my guess is that few would gripe.. but the
> masses just want to make qso's like the rest of us, and would in time
> oblige. I digress..have a great new year everyone & enjoy !
>
> -Steve Raas
> N2JDQ
>
>
> On Mon, Dec 30, 2013 at 10:55 PM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>> Thanks everyone for the suggestions. I'm going to have to install some
>> software to identify some of the signals.
>>
>>
>>
>> I would think that IMD products in a high-level PA that is over-driven
>>> beyond good linearity limits could add some junk in the "undesired
>>> sideband"? FWIW
>>>
>>>
>> IMD **requires** two or more signals at once, and does not appear
>> anything
>> like sideband leakage. This was a single shifting tone, and the lower
>> frequency signal went the opposite way but the same amount as the main
>> signal with shifts. That is classic for inadequate sideband suppression.
>>
>> There are multiple problems with using SSB to transmit audio tones and
>> "thinking" it is a pure digi mode.
>>
>> 1.) things like this do not show on almost all digi waterfalls because
>> they are out of passband of the other fellows receiver.
>>
>> 2.) SSB carrier, noise, and opposite sideband suppression is limited by
>> the radio quality
>>
>> 3.) output purity is also limited by audio input purity, which includes
>> audio line issues
>>
>> 4.) most digi operators do not have the low noise antennas most DXers
>> have, and cannot hear some fairly strong signals. They are often on
>> digimodes because of that!
>>
>> 5.) radios have terrible SSB transmitter performance compared to even
>> fair
>> receivers, so the transmitters often set the adjacent channel
>> interference
>> levels
>>
>> Placing digimodes near weak signal areas is not very wise frequency
>> planning, but there is nothing anyone can do about it.
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
> ------------------------------
>
> Message: 18
> Date: Mon, 30 Dec 2013 22:48:18 -0600
> From: Mike Waters <mikewate at gmail.com>
> To: topband <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID:
> <CA+FxYXjOemiJtEBo+HJsWjeeNBZvc8YVEwx8tgEQhoCJ-8Mfcg at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Maybe not.
>
> I got a private e-mail earlier (which I haven't had time to respond to
> yet)
> that stated "To see who is QRV on 160M WSPR at any given time, check at
> http://wsprnet.org/drupal/wsprnet/activity
> Scroll down to 160M and the stations are listed (those followed by an R
> are
> just receiving)."
>
> 73, Mike
> www.w0btu.com
>
> On Mon, Dec 30, 2013 at 9:55 PM, Tom W8JI <w8ji at w8ji.com> wrote:
>
>> Thanks everyone for the suggestions. I'm going to have to install some
>> software to identify some of the signals.
>>
>
>
> ------------------------------
>
> Message: 19
> Date: Tue, 31 Dec 2013 13:49:06 +0000
> From: "Shoppa, Tim" <tshoppa at wmata.com>
> Cc: "topband at contesting.com" <topband at contesting.com>
> Subject: Re: Topband: Stew Perry Streaming Audio
> Message-ID:
> <303A17BD5F8FA34DA45EEC245271AC0B949D647F at JGEX2K10MBX2.wmata.local>
> Content-Type: text/plain; charset="us-ascii"
>
> I always set these software-based goals before the test, but funny how
> they get delayed in the face of driving kids around to acitivities and
> stringing up antennas in the trees, and then when the sun goes down and
> the contest starts swinging, all those pie in the sky virtual dreams
> evaporate in the face of real QSO's to be made :-)
>
> I had a lot of fun in the Stew Perry and felt my new west-facing pennant
> was an improvement for stations in the deeper west and on west coast. I'm
> sure I didn't hear some low power California stations that tried to call
> me.
>
> Tim N3QE
> ________________________________________
> From: Shoppa, Tim
> Sent: Saturday, December 28, 2013 9:58 AM
> Cc: topband at contesting.com
> Subject: RE: Topband: Stew Perry Streaming Audio
>
> Streaming audio live during the contest doesn't seem particularly useful
> to me.
>
> But recordings made available post-contest over the web, those might be
> interesting to others. I'm going to see if I can set that up at my (much
> more modest) shack. I would love to hear what my signal sounds like on
> West Coast or in EU.
>
> Tim N3QE
>
> ________________________________________
> From: Topband [topband-bounces at contesting.com] on behalf of Tree
> [tree at kkn.net]
> Sent: Saturday, December 28, 2013 9:39 AM
> To: Eric NO3M
> Cc: Stan Stockton; topband at contesting.com; cq-contest at contesting.com;
> Clive GM3POI
> Subject: Re: Topband: Stew Perry Streaming Audio
>
> Perhaps a different approach is to make it available to people who are
> interested in hearing it. There are probably some people who are not able
> to operate the contest and would appreciate the opportunity to hear what
> it
> sounds like. Also - Eric is a top notch operator and being able to listen
> to how he uses two radios might be educational for some.
>
> I really doubt there is going to be abuse of this - despite what our
> imaginations come up with. I know K5ZD and others have done this for
> other
> major contests.
>
> Tree N6TR
>
>
> On Sat, Dec 28, 2013 at 3:39 AM, Eric NO3M <no3m at no3m.net> wrote:
>
>> Since there seems to be too much concern over this, though no ill intent
>> was intended, audio will not be broadcast.
>>
>> GL / 73 Eric NO3M
>>
>> On 12/28/2013 06:23 AM, Stan Stockton wrote:
>>
>>> Eric,
>>>
>>> You made it clear what you were doing, and I am quite sure Clive
>>> understood. I think the logic behind his question has to do with
>>> whether
>>> it is within the spirit of the contest - especially this one. Let's
>>> say,
>>> as a result of the announcement or advertisement , 15 DX stations and 25
>>> USA stations who are not even going to send in their log called you,
>>> just
>>> for fun and the novelty of it, so they could listen to their own signal
>>> at
>>> your end via Internet.
>>>
>>> What if some have enough QRM or QRN that they could only copy whether
>>> you
>>> came back to them by listening via internet? Fair to your competitors?
>>>
>>> It is cool, but I've always had a problem with this, regardless of what
>>> contest.
>>>
>>> 73...Stan, K5GO
>>>
>>> Sent from my iPad
>>>
>> _________________
>> Topband Reflector Archives - http://www.contesting.com/_topband
>>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
> ------------------------------
>
> Message: 20
> Date: Tue, 31 Dec 2013 09:21:38 -0500
> From: Barry N1EU <barry.n1eu at gmail.com>
> To: topBand List <topband at contesting.com>
> Subject: Topband: CA/OR/AZ activity during Stew Perry - anecdotal data
> Message-ID:
> <CAFmfzDsZyK07vxthFnRs141HN_9Q6uo8HpGSOQfHAUaO86pGmw at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
>
> I thought I'd share some data points from my Stew Perry log. Even though
> propagation to the west coast seemed good from upstate NY, I had the
> impression of less activity than expected from California so I looked
> closer at my log. What I found was 13 q's from California and 14 q's each
> from neighboring Oregon and Arizona (each with 1/7 of the ham population
> of
> CA). Perhaps the ham population in California is disproportionately
> urban/suburban with less topband activity, Californians disproportionately
> go QRP in SP or ???
>
> 73 & Happy New Year,
> Barry N1EU
>
>
> ------------------------------
>
> Message: 21
> Date: Tue, 31 Dec 2013 10:13:29 -0500
> From: "Tom W8JI" <w8ji at w8ji.com>
> To: "Charlie Cunningham" <charlie-cunningham at nc.rr.com>,
> <topband at contesting.com>
> Subject: Re: Topband: Digital mode spurious issues
> Message-ID: <952FFD43F713459C9780E88B677DE50E at MAIN>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> reply-type=original
>
>> Well, I certainly have to agree, Tom, if the signal on the desired
>> sideband
>> is just a single shifting tone. Might get messier if an sudio stage or
>> A/D
>> is driven into limiting and producing harmonic distortion at audio, I
>> guess.
>>
>
> The entire thing for digital modes was poorly planned. I'm surprised no
> one
> objected to the frequency choices (of Europe), because they are
> technically
> always going to be a long term problem. The frequency range really could
> not
> have been more poorly planned for future long-term band use.
>
> Any digital mode piped into the SSB transmitter system, like it or not, is
> really SSB modulated. It has all the noise, carrier, and opposite sideband
> suppression issues, as well as sensitivity to levels. If they transmit
> 1835-40 using USB on the radio, the opposite sideband falls in the 1832
> and
> upward range. IMD can be anywhere, if it is a multiple tone at the same
> time
> mode. Harmonic distortion is upward from the carrier on USB.
>
> Collins got burned by this. They tried running a pure audio tone into the
> SSB transmitter of the early S line to generate CW. The FCC (back when
> they
> did enforcement) starting handing out pink slips left and right to Collins
> owners. Any carrier, noise, or harmonic distortion at all resulted in an
> FCC
> citation, so Collins had to convert transmitters back to a keyed carrier.
>
> Anything converted to RF in a SSB transmitter system really belongs off by
> itself, well away from other operation. It's really a technical issue that
> will always exist, because the basic RF generation system or idea is
> flawed.
>
>
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> Topband mailing list
> Topband at contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
>
> ------------------------------
>
> End of Topband Digest, Vol 132, Issue 30
> ****************************************
>
>
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