Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mi05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 27ABE38000481; Thu, 3 Jan 2013 07:10:09 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Tqj3e-0008LM-Un for rs_out_1@blacksheep.org; Thu, 03 Jan 2013 11:33:58 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Tqj3e-0008LD-0e for rsgb_lf_group@blacksheep.org; Thu, 03 Jan 2013 11:33:58 +0000 Received: from imr-da01.mx.aol.com ([205.188.105.143]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1Tqj3Z-0002mc-N0 for rsgb_lf_group@blacksheep.org; Thu, 03 Jan 2013 11:33:56 +0000 Received: from mtaomg-db06.r1000.mx.aol.com (mtaomg-db06.r1000.mx.aol.com [172.29.51.204]) by imr-da01.mx.aol.com (Outbound Mail Relay) with ESMTP id 999B61C000068 for ; Thu, 3 Jan 2013 06:33:30 -0500 (EST) Received: from core-dfc001a.r1000.mail.aol.com (core-dfc001.r1000.mail.aol.com [172.29.55.3]) by mtaomg-db06.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 64133E000081 for ; Thu, 3 Jan 2013 06:33:30 -0500 (EST) References: <871180718.807959.1357202851097.JavaMail.open-xchange@email.1und1.de> To: rsgb_lf_group@blacksheep.org In-Reply-To: <871180718.807959.1357202851097.JavaMail.open-xchange@email.1und1.de> X-MB-Message-Source: WebUI MIME-Version: 1.0 From: Markus Vester X-MB-Message-Type: User X-Mailer: Webmail 37276-BASIC Received: from 194.138.39.61 by webmail-d164.sysops.aol.com (205.188.252.81) with HTTP (WebMailUI); Thu, 03 Jan 2013 06:33:30 -0500 Message-Id: <8CFB7BD49F0E58C-6E8-60E@webmail-d164.sysops.aol.com> X-Originating-IP: [194.138.39.61] Date: Thu, 3 Jan 2013 06:33:30 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1357212810; bh=TdhudcRMQqvvkTgB1+J1yykKAyUFYVKK2vwe1iiJXK0=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=RdbFv3HA4GEZFMPv/nYtS6//ADL3pUWXE29QOm5KqqkhBWeV05T0JkpGUcehebzVd LvAbfzc/uAiVbyoZ61Wf3FiRRMuQFigdjk96D+iOCqTqV4ppUjZ4WHKYxEegX6neFU v81+FaqYx2C6kx0tcWpzAGYIxAL+ZU7QaD7mEQ5o= X-AOL-SCOLL-SCORE: 0:2:507944096:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Geri, all,  I like the idea of trying voice on MF or even LF, and I was fascinated by actually hearing Gus talking on 507 kHz, and Geri on LF slow voice. I admit that I even tried (low-power daytime) SSB above 135.7 kHz once, and Stefan was actually able to hear and record my voice, albeit at marginal SNR at 180 km. As my LF TX antenna is fairly narrowband (Q ~ 200), I had inserted a phase shifter to transforme the low output impedance of the PA into a current source at the feedpoint.  The good thing about slow voice is that we also get the SNR gain associated with the narrower bandwidth. But the non-realtime operating procedure is sort of difficult. We did use "roger beeps" to mark the end of message., but there is always an inconvenient delay for recording and replaying the messages. So some sort of realtime narrowband voice transmission would indeed be desirable.  However I would NOT fancy digital voice modes all that. For one, like all digital modes its it's all-or-nothing. Either the message decodes well, or you get garbage, and you don't know what has been going on in the channel. In linear analog SSB, you hear if someone else is calling on frequency, or what type of interference came up, or whether there is selective fading. The other thing I don't like about digital modes is that they tend to occupy the whole channel permanently with high average power - just look at the spectra of DRM vs AM modulated BC transmissions. It may well turn out that a 2 kHz linear SSB transmission is much more friendly than a 1 kHz digital channel.  I have been making some attempts on analog quasi-realtime narrowband voice transmissions. The principle was is much the same that has long been used for changing audio speed without changing pitch, ie cut the audio into ~ 20 ms grains. To accellerate or reduce bandwidth, you either leave out or average several grains, using a sliding window. On replay, each grain is repeated to extend it in time. This is not difficult to implement. In my [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [205.188.105.143 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 31e464b680e3427073f16da582bb11f1 Subject: Re: LF: SSB - why not go digital? Content-Type: multipart/alternative; boundary="--------MB_8CFB7BD4A08B356_6E8_10E1_webmail-d164.sysops.aol.com" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.1 required=5.0 tests=HTML_FONTCOLOR_UNKNOWN, HTML_MESSAGE autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false x-aol-global-disposition: G X-AOL-SCOLL-AUTHENTICATION: mtain-mi05.r1000.mx.aol.com ; domain : mx.aol.com DKIM : pass x-aol-sid: 3039ac1d7b8d50e575214ab4 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ----------MB_8CFB7BD4A08B356_6E8_10E1_webmail-d164.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Hi Geri, all, =C2=A0 I like the idea of trying voice on MF or even LF,=C2=A0 and I=C2=A0was fasc= inated by actually hearing Gus=C2=A0talking on 507 kHz, and Geri on LF slow= voice.=C2=A0I=C2=A0admit that I even tried (low-power daytime) SSB=C2=A0ab= ove 135.7 kHz once, and Stefan was actually able to hear and record my voic= e, albeit at marginal SNR at 180 km. As my LF TX antenna is fairly narrowba= nd (Q=C2=A0~ 200), I had inserted a phase shifter to transforme the low out= put impedance of the PA into a current source at the feedpoint. =C2=A0 The good thing about slow voice is that we also get the SNR gain associated= with the narrower bandwidth. But the non-realtime operating procedure is= =C2=A0sort of=C2=A0difficult. We did use=C2=A0"roger beeps" to mark the end= =C2=A0of message., but there is always an inconvenient=C2=A0delay=C2=A0for = recording and replaying the messages.=C2=A0So some sort of realtime narrowb= and voice transmission=C2=A0would indeed=C2=A0be desirable. =C2=A0 However I would NOT fancy=C2=A0digital voice modes all that. For one, like = all digital modes its=C2=A0it's all-or-nothing. Either=C2=A0the message=C2= =A0decodes well,=C2=A0or you get garbage, and you don't know what has been = going on in the channel. In linear analog SSB, you hear if someone else=C2= =A0is calling on frequency,=C2=A0or=C2=A0what type of interference came up,= or whether there is selective fading. The other thing I don't like=C2=A0ab= out digital modes is that they tend to occupy the whole channel permanently= with high average power - just look at=C2=A0the spectra of DRM vs AM modul= ated BC transmissions. It may well turn out=C2=A0that a 2 kHz=C2=A0linear S= SB transmission is much more friendly than a 1 kHz digital channel.=C2=A0 =C2=A0 I have been making some attempts on analog quasi-realtime narrowband voice = transmissions. The principle was is much the same that has long been used f= or=C2=A0changing=C2=A0audio speed without changing pitch, ie cut the audio = into ~ 20 ms=C2=A0grains. To accellerate or reduce bandwidth,=C2=A0you eith= er=C2=A0leave out or average several=C2=A0grains, using a sliding window. O= n replay,=C2=A0each grain=C2=A0is repeated to extend it in time. This is no= t difficult to implement. In my own trials, I could maintain speech readabi= lity with a factor four bandwidth reduction, but it did sound very "robotic= " because=C2=A0the=C2=A0fixed timing for the grains impressed itself onto t= he voice pitch. I think that there are better ways of adapting the=C2=A0tim= ing=C2=A0by tracking the fundamental frequency=C2=A0to preserve the=C2=A0pi= tch modulation. Using Windows media player=C2=A0for accelerating and decele= rating seemed to provide=C2=A0quite=C2=A0natural speech=C2=A0quality at a r= eduction factor of four. =C2=A0 Regarding the frequency allocations, like Graham I would think that on MF t= he narrowband beacons should best be placed in narrow slots near the band e= dges. To avoid blocking,=C2=A0we would preferably again use split band for = west-east vs east-west intercontinental work, as we do on LF. Parts of thes= e slots should also be utilized for the slow versions of Opera or WSPR.=C2= =A0The wider modes would better be placed in the in the middle, perhaps wit= h=C2=A02 kHz each=C2=A0for=C2=A0CW,=C2=A0middle-range digital modes,=C2=A0a= nd=C2=A0one full-width SSB channel. Best 73, Markus (DF6NM) =C2=A0 -----Urspr=C3=BCngliche Mitteilung-----=20 Von: geri <geri@dk8kw.de> An: rsgb_lf_group <rsgb_lf_group@blacksheep.org> Verschickt: Do, 3 Jan 2013 10:09 am Betreff: LF: SSB - why not go digital? Have a look at FDMNV Hi,=20 =C2=A0=20 I just did some research and obviously there are people who already have th= ought about low bandwidth voice communications. There is a mode called FDMN= V, based on a common CODEC that transmits voice in a 1100 Hz bandwidt (see = http://n1su.com/fdmdv/).=20 =C2=A0=20 In the describtion of the software it says "it caters to high quality digit= al voice under poor band conditions, in only 1100Hz bandwidth" which probab= ly is the kind of features we are looking for. The software=C2=A0is open so= urce and surely worth to have acloser look at.=C2=A0=20 =C2=A0=20 Also, i am sure we (in Germany) can negotiate with our authorities to get a= n extension of our 800 Hz bandwidth limitation at least under certain condi= tions. For everyone without limitation this seems to be the software to jus= t go ahead and try it!=20 =C2=A0=20 =C2=A0=20 Best 73=20 =C2=A0=20 Geri, DK8KW=20 =C2=A0=20 =C2=A0=20 > > ----- Original Message -----=20 > > From: M0FMT=20 > > To: rsgb_lf_group@blacksheep.org=20 > > Sent: Thursday, January 03, 2013 12:30 AM=20 > > Subject: Re: LF: 477 A local SSB chat band ?=20 > >=20 > >=20 > > Hi Graham Geri and all=20 > >=20 > > Warren has seen SSB first hand on the MF QRG and we have this sid= e also.There was an SM station (call sign forgotten?) in the early days of = 500 that added an SSB anouncement on his beacon and it worked well.=20 > >=20 > > To my spec. :- "One SSB channel at the high edge of the band only= used during daylight hours no DXing!" add " Use VOX, no monologuing allowe= d" to be a laissez faire operation no band plan, but fair play!.73 es GL es= HNY Pete M0FMT IO91UX=20 > >=20 > > From: Graham <g8fzk@g8fzk.fsnet.co.uk>=20 > > To: rsgb_lf_group@blacksheep.org=20 > > Sent: Wednesday, 2 January 2013, 20:48=20 > > Subject: Re: LF: 477 A local SSB chat band ?=20 > >=20 > >=20 > >=20 > > Geri=20 > >=20 > > 800 Hz B/W ... May be this is something 'Wolf' can code for you ?= a b/w compression / expansion module in SL , to limit the tx b/w to 800 Hz= must be possible to divide by 3 and mult by 3 with a linear shift as well = ?=20 > >=20 > > G..=20 > >=20 > >=20 > > From: Holger 'Geri', DK8KW - DI2BO - W1KW=20 > > Sent: Wednesday, January 02, 2013 8:36 PM=20 > > To: rsgb_lf_group@blacksheep.org=20 > > Subject: Re: LF: 477 A local SSB chat band ?=20 > >=20 > >=20 > > Hi,=20 > >=20 > > I kind of like the idea of an SSB channel. I just pulled out the = conditions of my first secial license for 160m from 1973 or 1974. That said= 1815 to 1835 kHz with 10 Watts in CW, additionally one SSB channel for 183= 2 to 1835 kHz, so why not trying this on 630m, too? Here in Germany we are = currently limited to 800 Hz bandwidt but I am sure we can sork towards a sp= ecial license under certain conditions such as daylight operation only .. s= ounds good to me!=20 > >=20 > > Vy 73=20 > >=20 > > Geri, DK8KW=20 > >=20 ----------MB_8CFB7BD4A08B356_6E8_10E1_webmail-d164.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
Hi Geri, all,
 
I like the= idea of trying voice on MF or even LF,  and I was fascinated by = actually hearing Gus talking on 507 kHz, and Geri on LF slow voice.&nb= sp;I admit that I even tried (low-power daytime) SSB above 135.7 = kHz once, and Stefan was actually able to hear and record my voice, albeit = at marginal SNR at 180 km. As my LF TX antenna is fairly narrowband (Q = ;~ 200), I had inserted a phase shifter to transforme the low output impeda= nce of the PA into a current source at the feedpoint.
 
The good t= hing about slow voice is that we also get the SNR gain associated with the = narrower bandwidth. But the non-realtime operating procedure is sort o= f difficult. We did use "roger beeps" to mark the end of mes= sage., but there is always an inconvenient delay for recording an= d replaying the messages. So some sort of realtime narrowband voice tr= ansmission would indeed be desirable.
 
However I = would NOT fancy digital voice modes all that. For one, like all digita= l modes its it's all-or-nothing. Either the message decodes = well, or you get garbage, and you don't know what has been going on in= the channel. In linear analog SSB, you hear if someone else is callin= g on frequency, or what type of interference came up, or whether = there is selective fading. The other thing I don't like about digital = modes is that they tend to occupy the whole channel permanently with high a= verage power - just look at the spectra of DRM vs AM modulated BC tran= smissions. It may well turn out that a 2 kHz linear SSB transmiss= ion is much more friendly than a 1 kHz digital channel. 
 
I have bee= n making some attempts on analog quasi-realtime narrowband voice transmissi= ons. The principle was is much the same that has long been used for ch= anging audio speed without changing pitch, ie cut the audio into ~ 20 = ms grains. To accellerate or reduce bandwidth, you either le= ave out or average several grains, using a sliding window. On replay,&= nbsp;each grain is repeated to extend it in time. This is not difficul= t to implement. In my own trials, I could maintain speech readability with = a factor four bandwidth reduction, but it did sound very "robotic" because&= nbsp;the fixed timing for the grains impressed itself onto the voice p= itch. I think that there are better ways of adapting the timing b= y tracking the fundamental frequency to preserve the pitch modula= tion. Using Windows media player for accelerating and decelerating seemed to= provide quite natural speech quality at a reduction factor = of four.
 
Regarding = the frequency allocations, like Graham I would think that on MF the narrowb= and beacons should best be placed in narrow slots near the band edges. To a= void blocking, we would preferably again use split band for west-east = vs east-west intercontinental work, as we do on LF. Parts of these slots sh= ould also be utilized for the slow versions of Opera or WSPR. The wide= r modes would better be placed in the in the middle, perhaps with 2 kH= z each for CW, middle-range digital modes, and one= full-width SSB channel.
Best 73,
Markus (DF6NM)

 
-----Urspr=C3=BCngliche Mitteilung-----
Von: geri <geri@dk8kw.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Do, 3 Jan 2013 10:09 am
Betreff: LF: SSB - why not go digital? Have a look at FDMNV

Hi,
 
I just did some research and obviously there are people who already ha= ve thought about low bandwidth voice communications. There is a mode called= FDMNV, based on a common CODEC that transmits voice in a 1100 Hz bandwidt = (see http://n1su.com/fdm= dv/).
 
In the describtion of the software it says "it caters to high quality = digital voice under poor band conditions, in only 1100Hz bandwidth<= /STRONG>" which probably is the kind of features we are looking for. The so= ftware is open source and surely worth to have acloser look at.  =
 
Also, i am sure we (in Germany) can negotiate with our authorities to = get an extension of our 800 Hz bandwidth limitation at least under certain = conditions. For everyone without limitation this seems to be the software t= o just go ahead and try it!
 
 
Best 73
 
Geri, DK8KW
 
 
> > ----- Original Message -----
> > From: M0FMT
> > To: rsgb_lf_group= @blacksheep.org
> > Sent: Thursday, January 03, 2013 12:30 AM
> > Subject: Re: LF: 477 A local SSB chat band ?
> >
> >
> > Hi Graham Geri and all
> >
> > Warren has seen SSB first hand on the MF QRG and we have this sid= e also.There was an SM station (call sign forgotten?) in the early days of = 500 that added an SSB anouncement on his beacon and it worked well.
> >
> > To my spec. :- "One SSB channel at the high edge of the band only= used during daylight hours no DXing!" add " Use VOX, no monologuing allowe= d" to be a laissez faire operation no band plan, but fair play!.73 es GL es= HNY Pete M0FMT IO91UX
> >
> > From: Graham <g8fzk= @g8fzk.fsnet.co.uk>
> > To: rsgb_lf_group= @blacksheep.org
> > Sent: Wednesday, 2 January 2013, 20:48
> > Subject: Re: LF: 477 A local SSB chat band ?
> >
> >
> >
> > Geri
> >
> > 800 Hz B/W ... May be this is something 'Wolf' can code for you ?= a b/w compression / expansion module in SL , to limit the tx b/w to 800 Hz= must be possible to divide by 3 and mult by 3 with a linear shift as well = ?
> >
> > G..
> >
> >
> > From: Holger 'Geri', DK8KW - DI2BO - W1KW
> > Sent: Wednesday, January 02, 2013 8:36 PM
> > To: rsgb_lf_group= @blacksheep.org
> > Subject: Re: LF: 477 A local SSB chat band ?
> >
> >
> > Hi,
> >
> > I kind of like the idea of an SSB channel. I just pulled out the = conditions of my first secial license for 160m from 1973 or 1974. That said= 1815 to 1835 kHz with 10 Watts in CW, additionally one SSB channel for 183= 2 to 1835 kHz, so why not trying this on 630m, too? Here in Germany we are = currently limited to 800 Hz bandwidt but I am sure we can sork towards a sp= ecial license under certain conditions such as daylight operation only .. s= ounds good to me!
> >
> > Vy 73
> >
> > Geri, DK8KW
> >
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