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[195.171.43.25]) by mx.google.com with ESMTP id i2si13809815wie.6.2013.12.29.04.10.08 for ; Sun, 29 Dec 2013 04:10:09 -0800 (PST) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass header.i=@mx.aol.com Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1VxE6k-0003Al-M9 for rs_out_1@blacksheep.org; Sun, 29 Dec 2013 11:00:34 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1VxE6k-0003Ac-3Z for rsgb_lf_group@blacksheep.org; Sun, 29 Dec 2013 11:00:34 +0000 Received: from omr-d05.mx.aol.com ([205.188.109.202]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1VxE6h-0001lb-3Y for rsgb_lf_group@blacksheep.org; Sun, 29 Dec 2013 11:00:32 +0000 Received: from mtaout-mce01.mx.aol.com (mtaout-mce01.mx.aol.com [172.29.27.205]) by omr-d05.mx.aol.com (Outbound Mail Relay) with ESMTP id 2431F70002C7D for ; Sun, 29 Dec 2013 06:00:29 -0500 (EST) Received: from White (95-91-238-155-dynip.superkabel.de [95.91.238.155]) by mtaout-mce01.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id 798A8380000A4 for ; Sun, 29 Dec 2013 06:00:28 -0500 (EST) Message-ID: <8C09023FA2074CB380BC9CF1E7A514E3@White> From: "Markus Vester" To: References: <20C550A7D07741688C6A26E73CBCF741@White> <52BF4895.8080502@iup.uni-heidelberg.de> <52BF7E2A.9000002@iup.uni-heidelberg.de> <52BFD963.8020300@freenet.de> Date: Sun, 29 Dec 2013 12:00:29 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 12.0.1606 X-MimeOLE: Produced By Microsoft MimeOLE V12.0.1606 x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1388314829; bh=n7N7q0pSssbTpDdcSxwA8sqxF7SYnhoPGWaEvudQd3w=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=kijdgTgljv+FQhc30MuIADwTdHSJE2o8bDyDtyGicxcpkiyp4Rm4QoWqMyoqx19uM ZpnOHQQj+jtWL9pJyKEyWSDZlufF/3c/EFN1KAbbWaKE1fkIP42xKu8HfyUg9OB3w6 mj/fUja1wBrIUMKQaIe4ubPfFlJ82lQKGwWB5yUY= x-aol-sid: 3039ac1d1bcd52c000cc316e X-AOL-IP: 95.91.238.155 X-Spam-Score: 0.6 (/) 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 Wolf, I think Stefan was only trying to solve the simpler problem of generating a dual squarewave drive for his VLF PA, and was not aiming for amplitude modulated output yet. So when he transmits Opera we'll just have to live with ultra-strong keyclicks, devastating the 9 kHz band all over Europe ;-)) [...] Content analysis details: (0.6 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [205.188.109.202 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid 1.0 FREEMAIL_REPLY From and body contain different freemails X-Scan-Signature: b0c81be0f3328ec24fe2fd5b2fd44f86 Subject: Re: LF: VLF exciter Content-Type: multipart/alternative; boundary="----=_NextPart_000_001D_01CF048D.91727150" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30,HTML_MESSAGE, MISSING_OUTLOOK_NAME 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 Status: O X-Status: X-Keywords: X-UID: 3167 Dies ist eine mehrteilige Nachricht im MIME-Format. ------=_NextPart_000_001D_01CF048D.91727150 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Wolf, I think Stefan was only trying to solve the simpler problem of = generating a dual squarewave drive for his VLF PA, and was not aiming = for amplitude modulated output yet. So when he transmits Opera we'll = just have to live with ultra-strong keyclicks, devastating the 9 kHz = band all over Europe ;-))=20 But I remember that in 2011 we discussed about transmitting high-quality = Hell piccies. As you say, the Kahn technique with a separate AM = modulator is certainly a good and efficient option. At VLF, outphasing = (aka Chireix or LINC technique) between two half-bridges would be a = valid alternative. There's some software for the purpose (including = Basic source code ;-) on=20 df6nm.bplaced.net/VLF/chirppix_outphase.zip This works in conjunction with your SndOutpt audio utility, generating = the two outphasing carriers at the left and right stereo output. Best 73, Markus (DF6NM) From: wolf_dl4yhf=20 Sent: Sunday, December 29, 2013 9:12 AM To: rsgb_lf_group@blacksheep.org=20 Subject: Re: LF: VLF exciter My suggestion: Use two outputs from the stereo soundcard:=20 An "amplitude" and a "phase" channel. The output from the phase channel = will be a square wave, coherent, constant amplitude, fed to the divider = chain. The "amplitude" channel delivers, well, the amplitude (as a = waveform with variable voltage) which, after rectification, drives the = final voltage via an additional mosfet. I think the software option is = already there, and iirc it has been used (by Jim ?) for an LF PA. This way, you could even use amplitude shaping if the bandwidth (from = the hard-keyed PA) was a problem - which I don't think it is, on VLF. Cheers, Wolf=20 (p.s. problem with the "very long command lines" already fixed, new SL = version will be uploaded soon). Am 29.12.2013 02:43, schrieb Stefan Sch=E4fer: Am 28.12.2013 23:33, schrieb Markus Vester:=20 [...]=20 PS Any progress on bypassing the divider in your VLF transmit chain? Aaah, no, i forgot that. So i cannot transmit OP32 on VLF because it = would be incoherent then. So i have to key the PA via a VOX and OP32 = tones, still :-/ In this H bridge PA config, an exact 50% duty cycle isn't needed, so i = may actually remove the divider. But then i need a solid and defined = input signal wave form! How do i get an inverted signal then? A = transformer isn't possible since i like to have a wide frequency range = of the PA. So far it works from 10 Hz to > 100 kHz. With the frequency = divider, the wave form can be quite distorted, no problem unless the = peak reaches the necessary voltage level. So maybe it is better to build = the VOX circuit instead? Also i want to leave the PA circuit as it is, = for nostalgic reasons :-) Or do you have another idea? I remember that circuit with the XOR = gates... 73, Stefan/DK7FC ------=_NextPart_000_001D_01CF048D.91727150 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Wolf,
 
I think Stefan was only trying to solve = the simpler=20 problem of generating a dual squarewave drive for his VLF PA, and was = not aiming=20 for amplitude modulated output yet. So when he transmits Opera we'll = just have=20 to live with ultra-strong keyclicks, devastating the 9 kHz band all over = Europe=20 ;-)) 
 
But I remember that in 2011 we = discussed about=20 transmitting high-quality Hell piccies. As you say, the Kahn = technique=20 with a separate AM modulator is certainly a good and efficient option. = At=20 VLF, outphasing (aka Chireix or LINC technique) between two = half-bridges=20 would be a valid alternative. There's some software for the purpose = (including=20 Basic source code ;-) on
df6nm.bplaced= .net/VLF/chirppix_outphase.zip
This works in conjunction = with your SndOutpt=20 audio utility, generating the two outphasing carriers at the left and = right=20 stereo output.
 
Best 73,
Markus (DF6NM)

From: wolf_dl4yhf
Sent: Sunday, December 29, 2013 9:12 AM
To: rsgb_lf_group@blacksheep.org= =20
Subject: Re: LF: VLF exciter

My suggestion:

Use two outputs from = the stereo=20 soundcard:
An "amplitude" and a "phase" channel. The output from the = phase=20 channel will be a square wave, coherent, constant amplitude, fed to the = divider=20 chain. The "amplitude" channel delivers, well, the amplitude (as a = waveform with=20 variable voltage) which, after rectification, drives the final voltage = via an=20 additional mosfet. I think the software option is already there, and = iirc it has=20 been used (by Jim ?) for an LF PA.
This way, you could even use = amplitude=20 shaping if the bandwidth (from the hard-keyed PA) was a problem - which = I don't=20 think it is, on VLF.

Cheers,
  Wolf

 (p.s. = problem=20 with the "very long command lines" already fixed, new SL version will be = uploaded soon).

Am 29.12.2013 02:43, schrieb Stefan = Sch=E4fer:

Am=20 28.12.2013 23:33, schrieb Markus Vester:=20
[...]=20
 
PS Any progress on bypassing the = divider in=20 your VLF transmit chain?

Aaah, no, i forgot that. So i cannot transmit OP32 on = VLF=20 because it would be incoherent then. So i have to key the PA via a VOX = and=20 OP32 tones, still :-/

In this H bridge PA config, an exact 50% = duty=20 cycle isn't needed, so i may actually remove the divider. But then i = need a=20 solid and defined input signal wave form! How do i get an inverted = signal=20 then? A transformer isn't possible since i like to have a wide = frequency range=20 of the PA. So far it works from 10 Hz to > 100 kHz. With the = frequency=20 divider, the wave form can be quite distorted, no problem unless the = peak=20 reaches the necessary voltage level. So maybe it is better to build = the VOX=20 circuit instead? Also i want to leave the PA circuit as it is, for = nostalgic=20 reasons :-)
Or do you have another idea? I remember that circuit = with the=20 XOR gates...

73,=20 Stefan/DK7FC

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