Return-Path: X-Spam-DCC: paranoid 1233; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id tBDD3ieO016300 for ; Sun, 13 Dec 2015 14:03:45 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1a86Ga-0004aU-LS for rs_out_1@blacksheep.org; Sun, 13 Dec 2015 13:00:44 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1a86GZ-0004aC-U7 for rsgb_lf_group@blacksheep.org; Sun, 13 Dec 2015 13:00:43 +0000 Received: from mail-wm0-f52.google.com ([74.125.82.52]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.86) (envelope-from ) id 1a86FO-00077c-9g for rsgb_lf_group@blacksheep.org; Sun, 13 Dec 2015 13:00:42 +0000 Received: by mail-wm0-f52.google.com with SMTP id p66so11473067wmp.0 for ; Sun, 13 Dec 2015 04:59:15 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=bJQp2UyKfvjJgAHyuyyhCr9XMw+OXDejkeXs93pDzlk=; b=vwmvMdRsUfRiujgpi2TvpML45+11vH23pl5Yy9nuVcO78rhFxowZgp5AMOoQGB0zxA Bchp0bAsyyaOokg90CrLA62rc57Hc5o3XPmZzwN35h7JjqVi7+kSZkrzLVqMHvmTXcV0 zvt5MBSMqFz6AFoTKNm+JDBVmdPvxef2Wmdscti/9OxdXA1g8dcR62+p7eEE5210lp78 zksOC/4EjJXHE6EuBqW1Myif2WCbsTErl9+OkuKUAR0Phnl8iOdFvpgEdlmLXsWIpDW8 3+UDhL8SckDp+idWJwUXCrxOfqBYZUrAewDkgAOUvc1RYOobXDF4/tJ8hlubkVAnBi18 yixA== MIME-Version: 1.0 X-Received: by 10.194.236.228 with SMTP id ux4mr32068289wjc.56.1450011554168; Sun, 13 Dec 2015 04:59:14 -0800 (PST) Received: by 10.28.130.139 with HTTP; Sun, 13 Dec 2015 04:59:14 -0800 (PST) In-Reply-To: <566D6597.4070901@freenet.de> References: <56686FA0.4050707@gmail.com> <56695B15.6010203@abelian.org> <56696950.1040300@abelian.org> <5669B7CE.1090601@freenet.de> <5669E1E3.6070008@abelian.org> <566D6597.4070901@freenet.de> Date: Sun, 13 Dec 2015 12:59:14 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org X-Scan-Signature: 5bc6e377a7e48238fb2d1143b58fab98 Subject: Re: LF: LF EbNaut test from JN80 on 137370 Content-Type: multipart/alternative; boundary=089e01493ed69b47d40526c71f49 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-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 5790 --089e01493ed69b47d40526c71f49 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable The terms "leading" and "lagging" are the most confusing terms I've ever come across in AC. A waveform on a scope, to the right of another one looks as if its leading it. But it is later in time - so its lagging. See my point ? On 13 December 2015 at 12:33, Wolfgang B=C3=BCscher wro= te: > Just to confirm (answer a bit late).. > > In a file recorded by SpectraVue (the software which came along with the > SDR-IQ), with the VFO tuned to 77490 Hz, recodring DCF77 on 77500 Hz, > produces a 'positive' 10 Hz baseband frequency in the I+Q wave file > recorded by that software. > And, as expectable for "I" ~ cos(omega*t) and "Q" ~ sin(omega*t), the > phase of the signal's "I" component *leads* the "Q" component by 90 > degrees. So, "all ok" with the files recorded by whatever software. > > Besides that, it's advisable *not* to tune the SDR exactly to the > frequency of the EbNaut signal. Detune by a few Hz to avoid having the "0 > Hz" component (after the downconversion, either digital or analog) inside > the decoder's passband. > > Now back to local EbNaut testing... > > Have a nice sunday an a merry xmas season everyone, > Wolf . > > > Am 12.12.2015 um 13:12 schrieb Andy Talbot: > > Hit send too soon on the last one > > On 12 December 2015 at 12:06, Andy Talbot wrote: > >> I've just added a fine tune to the PC prog to shift teh input frequeny b= y >> any amount specified in a text box >> >> > > >> { ipI& and ipQ& are the input samples from the receiver } >> > > >> LOtheta =3D Val(Tuning.Text) / Fsample >> LocalOsc =3D LocalOsc + LOtheta 'Both are >> normalised frequencies (Fsample =3D 1) >> LocalOsc =3D LocalOsc - Int(LocalOsc) 'Fractional part = only >> theta =3D 2 * pi * LocalOsc >> >> IPData(DataPointer&, 0) =3D ipI& * Cos(theta) - ipQ& * >> Sin(theta) ' I >> IPData(DataPointer&, 1) =3D ipQ& * Cos(theta) + ipI& * >> Sin(theta) ' Q >> >> The effect of that is for any positive freqeuncy in Hz intereed into > Tuning.text , the spectrum plot shift positive, and conversely the displa= y > shifts wown for any -ve value entered > > Andy G4JNT > >> >> >>> >>> On 10 December 2015 at 20:34, Paul Nicholson >>> wrote: >>> >>>> >>>> In vlfrx-tools I use >>>> >>>> I =3D s(t) * cos( 2pi * Fo * t); >>>> >>>> Q =3D s(t) * sin( 2pi * Fo * t); >>>> >>>> where s(t) is the incoming signal and Fo is the >>>> local oscillator frequency. Is that right, or >>>> should there be a minus sign in there somewhere? >>>> >>>> If s(t) is VO1NA at 137370.00000 and I set Fo to >>>> 137369.9, then when I put I and Q into EbNaut, it >>>> needs an offset of +0.1 Hz to decode as you would >>>> expect with the LO being 0.1Hz on the low side. >>>> >>>> For more general mixing and frequency shift, >>>> to select the upper sideband of the mixer output >>>> I use >>>> >>>> I - j * Q >>>> >>>> is that the right way round? When I take I/Q data >>>> from an RTL2832 I find I have to invert Q to get the >>>> correct sideband, ie I + j * Q. That's the only >>>> independent source of I/Q signal that I have available >>>> to try. >>>> >>>> -- >>>> Paul Nicholson >>>> -- >>>> >>>> >>> >> > > --089e01493ed69b47d40526c71f49 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
The terms "leading" and "lagging"= are the most confusing terms I've ever come across in AC.=C2=A0 A wave= form on a scope, to the right of another one looks as if its leading it.=C2= =A0=C2=A0 But it is later in time - so its lagging.

See my point ?



On 13 December 2015 at 12:33, Wolf= gang B=C3=BCscher <dl4yhf@freenet.de> wrote:
=20 =20 =20
Just to confirm (answer a bit late)..

In a file recorded by SpectraVue (the software which came along with the SDR-IQ),=C2=A0 with the VFO tuned to 77490 Hz, recodring DCF77 on 77500 Hz, produces a 'positive' 10 Hz baseband frequency in the= I+Q wave file recorded by that software.
And, as expectable for "I" ~ cos(omega*t) and "Q" ~= sin(omega*t), the phase of the signal's "I" component *leads* the "= ;Q" component by 90 degrees. So, "all ok" with the files recorded by whatever software.

Besides that, it's advisable *not* to tune the SDR exactly to the frequency of the EbNaut signal. Detune by a few Hz to avoid having the "0 Hz" component (after the downconversion, either digita= l or analog) inside the decoder's passband.

Now back to local EbNaut testing...

Have a nice sunday an a merry xmas season everyone,
=C2=A0=C2=A0 Wolf .


Am 12.12.2015 um 13:12 schrieb Andy Talbot:
Hit send too soon on the last one

On 12 December 2015 at 12:06, Andy Talbot <andy.g4jnt@gmail.com> wrote:
I've just added a fine tune to the PC pr= og to shift teh input frequeny by any amount specified in a text box
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0
=C2=A0
=C2=A0 { =C2=A0ipI& and ipQ& are the input sam= ples from the receiver =C2=A0}
=C2=A0
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 LOtheta =3D = Val(Tuning.Text) / Fsample =C2=A0
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 LocalOsc = =3D LocalOsc + LOtheta =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 'Both are normalised frequencies (Fsa= mple =3D 1)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 LocalOsc = =3D LocalOsc - Int(LocalOsc) =C2=A0 =C2=A0 =C2=A0'Fractional part only
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 theta =3D = 2 * pi * LocalOsc
=C2=A0=C2=A0
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 IPData(Dat= aPointer&, 0) =3D ipI& *=C2=A0Cos(theta)=C2=A0- ipQ& * Sin(theta)= =C2=A0 =C2=A0 =C2=A0 ' =C2=A0 =C2=A0I
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 IPData(Dat= aPointer&, 1) =3D ipQ& *=C2=A0Cos(theta)=C2=A0+ ipI& * Sin(theta)= =C2=A0 =C2=A0 =C2=A0' =C2=A0 Q

The effect of that is for any positive freqeuncy in Hz intereed into Tuning.text , the spectrum plot shift positive, and conversely the display shifts wown for any -ve value entered

Andy =C2=A0G4JNT



On 10 December 2015 at 20:34, Paul Nicholson <= vlf0403@abelian.org> wrote:

In vlfrx-tools I use

=C2=A0I =3D s(t) * cos( 2pi * Fo * t);

=C2=A0Q =3D s(t) * sin( 2pi * Fo * t);

where s(t) is the incoming signal and Fo is the
local oscillator frequency.=C2=A0 =C2=A0Is th= at right, or
should there be a minus sign in there somewhere?

If s(t) is VO1NA at 137370.00000 and I set Fo to
137369.9, then when I put I and Q into EbNaut, it
needs an offset of +0.1 Hz to decode as you would
expect with the LO being 0.1Hz on the low side.

For more general mixing and frequency shift,
to select the upper sideband of the mixer output
I use

=C2=A0 =C2=A0I - j * Q

is that the right way round?=C2=A0 =C2=A0When= I take I/Q data
from an RTL2832 I find I have to invert Q to get the
correct sideband, ie I + j * Q.=C2=A0 =C2=A0T= hat's the only
independent source of I/Q signal that I have available
to try.

--
Paul Nicholson
--






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