Topband: Digial mode spurious issues

[Joe Subich, W4TV]

More and more are starting to do so with the Freescale modules - they
are certainly *not* linear at 1200W from a single module.  Maybe a
pair will handle 1500W and be linear - I haven't seen a full set of
parameters.

73,

    ... Joe, W4TV


On 1/2/2014 10:12 PM, Carl wrote:
> But very few EME ops run Class C amps.
>
> Carl
> KM1H
>
>
> ----- Original Message ----- From: "Joe Subich, W4TV" <lists at subich.com>
> To: <topband at contesting.com>
> Sent: Wednesday, January 01, 2014 10:56 PM
> Subject: Re: Topband: Digial mode spurious issues
>
>
>>
>> > 1 } Improperly adjusted sound card interface i.e. over driven and
>> > drawing ALC (remember it is a digital signal)
>>
>> JT65 and JT9 are single tone at a time modes and are designed to be
>> operated with class C amplifiers - as is common in EME operation.
>> ALC is not an issue but improperly adjusted sound cards (clipping),
>> overdriven microphone inputs (clipping in the mic preamp) and band
>> audio returns (grounds) are all common causes of distorted signals.
>>
>> > 2} A poorly operating SSB transceiver where the opposite sideband has
>> > poor suppression. This type of transceiver will most likely QRM
>> > someone even if on CW or SSB.
>>
>> Poorly adjusted SSB transceivers - poor carrier suppression, bad
>> opposite sideband rejection - are the biggest issue.
>>
>> > 3.) He was running way way too much power. I never operate with more
>> > than 30 watts {its a low power mode.. I worked VK5BC with 30w on TB
>> > ........try that with CW)
>>
>> JT65 and JT9 are *not* "low power modes.  They are *weak signal* modes
>> - there is a big difference.  The genesis of Joe Taylor's modes was
>> EME and meteor scatter communications where "full gallon" transmitters
>> are normal and signals are still weak.  Nobody with an understanding of
>> the history of JT4, JT6, JT9, JT65, FSK441, etc. would ever call them
>> "low power" modes or suggest EME and MS operators run 30 watts or less.
>>
>> 73,
>>
>>    ... Joe, W4TV
>>
>>
>> On 1/1/2014 9:39 PM, Jim wrote:
>>> Tom and all, T he signal you describe is indeed a JT65 signal and you
>>> can either use JT65HF OR WSJT-X to decode it but might I submit that
>>> the problem was with:
>>>
>>>
>>> 1 } Improperly adjusted sound card interface i.e. over driven and
>>> drawing ALC (remember it is a digital signal)
>>>
>>>
>>> 2} A poorly operating SSB transceiver where the opposite sideband has
>>> poor suppression. This type of transceiver will most likely QRM
>>> someone even if on CW or SSB.
>>>
>>>
>>> 3.) He was running way way too much power. I never operate with more
>>> than 30 watts {its a low power mode.. I worked VK5BC with 30w on TB
>>> ........try that with CW)
>>>
>>>
>>> As a general rule all stations operating digital use USB now on all
>>> bands but the program does not care which sideband you use the
>>> transceiver sets that
>>>
>>>
>>> Remember that the signal that enters the transceiver is digital and
>>> as such will splatter if the signal input draws any appreciable ALC
>>>
>>>
>>> I agree that if a particular signal was being heard on 33 he had a
>>> problem of some type. If you find him again I would be willing to
>>> make first contact ... I understand what signals should sound like
>>> and look like on the display. I only suggest this because this mode
>>> is kinda unique and uses (for the most part) canned messages.
>>>
>>>
>>> Now to why digital is where it is in the band.. although we have been
>>> here before....it is not by chance that digital is at that spot in
>>> the band. They want to have QSOs with DX stations too and there are a
>>> lot of countries that don't allow operation down the bottom of the
>>> band but they do allow operation 1930-1950. Besides IF someone misses
>>> these few KHz we have a major problem with the way we are operating.
>>> Next I can and have operated CW directly among a whole wack of JT65
>>> they didn,t know the difference and neither did I and if I can do it
>>> with the TINITUS others can do it.
>>>
>>>
>>>
>>>
>>> By the way operating digital is not about being an elite operator as
>>> someone suggested in one of the local chat rooms, its about doing
>>> something different and forging new ground.. or as James T. Kirk
>>> called it .. "Going where no one has gone before"
>>>
>>>
>>> Jim
>>>
>>> Long Live Seal Team VI
>>>
>>> http://www.qsl.net/wa3mej/index.htm ----- Original Message -----
>>> From: topband-request at contesting.com To: topband at contesting.com Sent:
>>> Wednesday, January 1, 2014 12:00:12 PM Subject: Topband Digest, Vol
>>> 133, Issue 1
>>>
>>> Send Topband mailing list submissions to topband at contesting.com
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
>>> http://lists.contesting.com/mailman/listinfo/topband or, via email,
>>> send a message with subject or body 'help' to
>>> topband-request at contesting.com
>>>
>>> You can reach the person managing the list at
>>> topband-owner at contesting.com
>>>
>>> When replying, please edit your Subject line so it is more specific
>>> than "Re: Contents of Topband digest..."
>>>
>>>
>>> Today's Topics:
>>>
>>> 1. Re: Digial mode spurious issues (Mike Greenway) 2. Re: Digial mode
>>> spurious issues (Joe Subich, W4TV) 3. Re: Digial mode spurious issues
>>> (Mike Waters) 4. Re: Digital mode spurious issues (Tom W8JI)
>>>
>>>
>>> ----------------------------------------------------------------------
>>>
>>>  Message: 1 Date: Tue, 31 Dec 2013 17:10:27 -0500 From: "Mike
>>> Greenway" <K4PI at BELLSOUTH.NET> To: <topband at contesting.com> Subject:
>>> Re: Topband: Digial mode spurious issues Message-ID:
>>> <52A7C61BC0414D61A4DD6EB286A01A81 at SHACK> Content-Type: text/plain;
>>> charset="utf-8"
>>>
>>> I don?t am still puzzled why the digital modes decided to use the
>>> 1837 to 1839 area with the size of the 160 M band. I know the SSB
>>> guys use a lot of the 1840-1900 area but 1900 to 2000 is usable isn?t
>>> it? I rarely hear much up there and 3 or 4 khz up there would never
>>> be missed. Probably not an answer but it has seemed strange to me
>>> since they started operating in that area. Some of their signals are
>>> bone crushing and wide. 73 Mike K4PI
>>>
>>> From: topband-request at contesting.com Sent: Tuesday, December 31, 2013
>>> 12:00 PM To: topband at contesting.com Subject: Topband Digest, Vol 132,
>>> Issue 30
>>>
>>> Send Topband mailing list submissions to topband at contesting.com
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
>>> http://lists.contesting.com/mailman/listinfo/topband or, via email,
>>> send a message with subject or body 'help' to
>>> topband-request at contesting.com
>>>
>>> You can reach the person managing the list at
>>> topband-owner at contesting.com
>>>
>>> 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
>>> ****************************************
>>>
>>> ------------------------------
>>>
>>> Message: 2 Date: Tue, 31 Dec 2013 17:51:52 -0500 From: "Joe Subich,
>>> W4TV" <lists at subich.com> To: topband at contesting.com Subject: Re:
>>> Topband: Digial mode spurious issues Message-ID:
>>> <52C34A88.3010206 at subich.com> Content-Type: text/plain;
>>> charset=windows-1252; format=flowed
>>>
>>>
>>> On 12/31/2013 5:10 PM, Mike Greenway wrote:
>>>> I don?t am still puzzled why the digital modes decided to use the
>>>> 1837to 1839 area with the size of the 160 M band.
>>>
>>> For the same reason the SSB guys insist on using 1840-1850 ... with
>>> their significantly smaller band (1810-1850 in some cases) Region 1
>>> put digital between CW (1810-1830) and SSB (1840-1850). With what is
>>> left of the "DX Window" at 1830-1835 that left 1835-1840 for
>>> digital.
>>>
>>> It's an unavoidable fact of life that new activity will go where the
>>> existing activity is. Look at digital on 40 meters - it is almost all
>>> between 7030/7035 and 7045 because that's where the EU and JA
>>> stations are. 160 is no different, digital activity in EU is
>>> 1835-1840 so that's where everyone else will be if they want a chance
>>> to work EU. As much as it pains me to say it - if you want to fix the
>>> situation get ITU to expand the 160 meter band in Region 1 and
>>> convince IARU Region 1 to relocate both digital and SSB activity
>>> higher/into the expanded band.
>>>
>>> 73,
>>>
>>> ... Joe, W4TV
>>>
>>>
>>> On 12/31/2013 5:10 PM, Mike Greenway wrote:
>>>> I don?t am still puzzled why the digital modes decided to use the
>>>> 1837to 1839 area with the size of the 160 M band. I know the SSB
>>>> guys use a
>>> lot of the 1840-1900 area but 1900 to 2000 is usable isn?t it? I
>>> rarely hear much up there and 3 or 4 khz up there would never be
>>> missed. Probably not an answer but it has seemed strange to me since
>>> they started operating in that area. Some of their signals are bone
>>> crushing and wide. 73 Mike K4PI
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 3 Date: Tue, 31 Dec 2013 17:29:57 -0600 From: Mike Waters
>>> <mikewate at gmail.com> To: Mike Greenway <K4PI at bellsouth.net>, topband
>>> <topband at contesting.com> Subject: Re: Topband: Digial mode spurious
>>> issues Message-ID:
>>> <CA+FxYXimxpes9qB+SafJF2JdnM1fAvtrFd0NuBKOOg3ohw9Nbg at mail.gmail.com>
>>> Content-Type: text/plain; charset=windows-1252
>>>
>>> Absolutely! From what I see from my QTH in SW MO, 1845 would be a
>>> good place for JT65 to move to. There is a ragchew group that meets
>>> on 1850, but seldom is there much activity below that.
>>>
>>> I seldom listen much above 1900. Maybe you're right, that would be a
>>> better place. But they definitely need to move up, as there's often
>>> DX just below them and we are just not going to get everyone to
>>> transmit a clean digital signal.
>>>
>>> By the way, Mike, it's easy to trim the large amount of text off the
>>> end of your messages with Shift-Ctrl-End and then Delete. :-) I've
>>> noticed others here forgetting to do that lately, too.
>>>
>>> 73, Mike www.w0btu.com
>>>
>>>
>>> On Tue, Dec 31, 2013 at 4:10 PM, Mike Greenway <K4PI at bellsouth.net>
>>> wrote:
>>>
>>>> I don?t am still puzzled why the digital modes decided to use the
>>>> 1837 to 1839 area with the size of the 160 M band. I know the SSB
>>>> guys use a lot of the 1840-1900 area but 1900 to 2000 is usable
>>>> isn?t it? I rarely hear much up there and 3 or 4 khz up there would
>>>> never be missed. Probably not an answer but it has seemed strange
>>>> to me since they started operating in that area. Some of their
>>>> signals are bone crushing and wide. 73 Mike K4PI
>>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 4 Date: Tue, 31 Dec 2013 19:14:13 -0500 From: "Tom W8JI"
>>> <w8ji at w8ji.com> To: <topband at contesting.com> Subject: Re: Topband:
>>> Digital mode spurious issues Message-ID:
>>> <18EE60A52F2A4E9182529136341FE673 at MAIN> Content-Type: text/plain;
>>> format=flowed; charset="iso-8859-1"; reply-type=response
>>>
>>>> AFAIK, all non-DSP rigs with synthesizers work this way. Assuming
>>>> you want the output frequency to be derived from the master clock
>>>> frequency, there is no easy way to shift an RF carrier. You can't
>>>> use a free running oscillator, because it won't be derived from the
>>>> master clock frequency. You can't switch between a mark synthesizer
>>>> and a space synthesizer because of transients. If you try to key
>>>> the programmed frequency of a BFO synthesizer, the PLL will
>>>> probably go out of lock momentarily, producing garbage. Also, it
>>>> may not be fast enough to keep up with RTTY. After considering all
>>>> this (as a very experienced synthesizer designer) it is hard for me
>>>> to blame the designers for using AFSK.
>>>
>>> It is easy to do it much better, and it would only cost pennies extra
>>> at the most. The signal could be generated by the normal SSB system
>>> and then run through a narrow IF filter. Problem solved. They could
>>> have done CW the same way, or in a similar fashion, with an unshaped
>>> off-on carrier through a narrow filter. They just didn't think to use
>>> the parts they already had in the radio.
>>>
>>> But that isn't this issue. This issue is they run baseband audio from
>>> a computer into a SSB transmitter to generate TX signals. This means
>>> it is really a SSB transmitter processing the tones, and they don't
>>> even restrict bandwidth with a narrow filter. That is really the
>>> entire issue. Instead of a narrow filter cleaning up stuff, it all
>>> goes through a SSB filter. Anyone with a computer and a little skill
>>> can invent a "new mode". It's just bad engineering to stick that
>>> stuff near weak signals, because the problem can only be fixed at the
>>> transmitter.
>>>
>>> 73 Tom
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Subject: Digest Footer
>>>
>>> _______________________________________________ Topband mailing list
>>> Topband at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/topband
>>>
>>>
>>> ------------------------------
>>>
>>> End of Topband Digest, Vol 133, Issue 1
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