Return-Path: Received: from mtain-de09.r1000.mx.aol.com (mtain-de09.r1000.mx.aol.com [172.29.64.209]) by air-dd04.mail.aol.com (v129.4) with ESMTP id MAILINDD042-86324ccd3f2919f; Sun, 31 Oct 2010 06:04:25 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-de09.r1000.mx.aol.com (Internet Inbound) with ESMTP id 3380D380000DF; Sun, 31 Oct 2010 06:04:22 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PCUke-0007uf-Kc for rs_out_1@blacksheep.org; Sun, 31 Oct 2010 10:03:00 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PCUke-0007uW-1x for rsgb_lf_group@blacksheep.org; Sun, 31 Oct 2010 10:03:00 +0000 Received: from mail-iw0-f171.google.com ([209.85.214.171]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PCUkb-0003ms-G8 for rsgb_lf_group@blacksheep.org; Sun, 31 Oct 2010 10:03:00 +0000 Received: by iwn35 with SMTP id 35so2115195iwn.16 for ; Sun, 31 Oct 2010 03:02:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=dsmBLV5gvtHYPNqohxunRIJ/gLrxsnZrQ4YUTqhPvgk=; b=mED0LnSAQEpzoSiB4g0GGcRptPZf2RdtQkSgoY5FgafcdAc5COKmZmvdHRBjJh4bHH dIUC2W1HPsT79oTlG/KSR06u0MvZ0bwOhHLqs6mDzGugtL0lPkCbIJFMGx/Kk+hv7lbK l+uHyuIgwg+ij1Z7SHfWC1/uZdM067cGbI/3w= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=xgmKZCnitnBVVRlHQ4VAPmsSubppG5Vv8vh734ebBiagOIDI4erdgimlQsYSwrKKrm 1uuBGS4DbY7HR7WFyqFxSlFCd27FH17lowF4JM4511r7bjsCKuUxCp7nzCfhFNwBY1m9 Btk4lPNbbDnCDsnhYF3OxQYTDdWirKBofFUA8= MIME-Version: 1.0 Received: by 10.231.35.200 with SMTP id q8mr12590657ibd.191.1288519374243; Sun, 31 Oct 2010 03:02:54 -0700 (PDT) Received: by 10.231.79.69 with HTTP; Sun, 31 Oct 2010 03:02:54 -0700 (PDT) In-Reply-To: <4CCD3CEA.5020200@iup.uni-heidelberg.de> References: <4CCC8022.90003@iup.uni-heidelberg.de> <004e01cb7883$96949580$4001a8c0@lark> <4CCCA351.1070508@iup.uni-heidelberg.de> <4CCD3CEA.5020200@iup.uni-heidelberg.de> Date: Sun, 31 Oct 2010 10:02:54 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: Re: SBL-3+ Content-Type: multipart/alternative; boundary=002215048a439688cc0493e6cbeb X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_20_30,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: mail_rly_antispam_dkim-d302.1 ; domain : googlemail.com DKIM : pass x-aol-sid: 3039ac1d40d14ccd3f255a21 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --002215048a439688cc0493e6cbeb Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Use a fast bus switch like the FS3125, and you may get a slightly better performance than HCMOS can offer. You could adapt the mixer from this upconverter design http://www.g4jnt.com/LFUpconv.pdf Andy www.g4jnt.com 2010/10/31 Stefan Sch=E4fer > Hi Rik, > > Very interesting! Looks easy, almost perfect. But i don't know what is= the > "best" solution now. It gets confusing the more solutions become availab= le. > Probably each method can achieve optimal results if built correctly. I= think > i will try a lot in the next days.. > > Tnx! > > 73, Stefan > > Am 31.10.2010 10:42, schrieb Rik Strobbe: > >> Hello Stefan, Alan, >> >> what about a CMOS analog switch mixer ? Cheap and easy to find. >> I used a 74HC4053 as mixer in my 3.5MHz to 500kHz transverter. >> Have a look at http://home4.swipnet.se/~w-41522/lfconv/lfconv.html(SM6L= KM), wher Johan shows a LF to 4MHz converter with a 74HC4053 mixer. >> Just adapt the LO and output circuitery for LF output. >> >> 73, Rik ON7TD - OR7T >> >> ________________________________________ >> Van: owner-rsgb_lf_group@blacksheep.org [ >> owner-rsgb_lf_group@blacksheep.org] namens Stefan Sch=E4fer [ >> schaefer@iup.uni-heidelberg.de] >> Verzonden: zondag 31 oktober 2010 0:59 >> Aan: rsgb_lf_group@blacksheep.org >> Onderwerp: Re: LF: Re: SBL-3+ >> >> Hi Alan, >> >> I want to try an alternative to the BF981 which runs in my current LF >> grabber RX. It downconverts 137 kHz to 12 kHz and feeds the soundcard >> with this 12 kHz signal. It is running not too bad but i have some >> problems with temperature drifting bandpass filters (since weeks) and >> have thrown them out of the Drain-to-Plus path. So, now the setup is >> running with a 2 stage RC LPF. I have had some problems with a to high >> 125 kHz level on the soundcard input and have applied a series LC >> circuit for 125 kHz now which reasonably solved the problem. But the LF >> noise is now just about 10 dB above the soundcard noise, in the >> afternoon. There is still a lack of sensitivity. This RX QTH should be >> very well for a grabber antenna but currently the setup is the problem. >> So i want to try something different, like a DBM. I am not an expert >> here and can/have to learn a lot, it seems ;-) >> >> 73, Stefan >> >> Am 31.10.2010 00:41, schrieb Alan Melia: >> >> >>> Hi Stefan why a difficult to get mixer?? the IF port on most DBMs is= DC >>> coupled so feed the siganl in there and (i presume) mix up ?? Or is th= e >>> RF/LO response still too high on the easily available ones? >>> >>> Alan G3NYK >>> ----- Original Message ----- >>> From: "Stefan Sch=E4fer" >>> To: >>> Sent: Saturday, October 30, 2010 9:29 PM >>> Subject: LF: SBL-3+ >>> >>> >>> >>> >>> >>>> Dear LF, >>>> >>>> I want to try a LF converter using this mixer. Does anybody know a >>>> (cheep!) distributor in Germany or EU for 1...3 pieces of it? I've ju= st >>>> found one where it costs about 40 Euro and this is to much!! >>>> >>>> 73, Stefan/DK7FC >>>> >>>> >>>> >>>> >>> >>> >> > --002215048a439688cc0493e6cbeb Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Use a fast bus switch like the FS3125, and you may get a slightly bet= ter performance than HCMOS=A0can offer.=A0=A0
=A0
You could adapt the mixer from this upconverter design http://www.g4jnt.com/LFUpconv.pdf
=A0
2010/10/31 Stefan Sch=E4fer &= lt;schaefer@iup.uni-heid= elberg.de>
Hi Rik,

Very interestin= g! Looks easy, almost perfect. But i don't know what is the "best= " solution now. It gets confusing the more solutions become available= . Probably each method can achieve optimal results if built correctly. I= think i will try a lot in the next days..

Tnx!

73, Stefan

Am 31.10.2010 10:42, schrieb Rik Strobbe= :
Hello Stefan, Alan,

wha= t about a CMOS analog switch mixer ? Cheap and easy to find.
I used a= 74HC4053 as mixer in my 3.5MHz to 500kHz transverter.
Have a look at http://home4.swipnet.se/~w-41522/lfconv/lfconv.html= (SM6LKM), wher Johan shows a LF to 4MHz converter with a 74HC4053 mix= er. Just adapt the LO and output circuitery for LF output.

73, Rik =A0ON7TD - OR7T

_______________________________________= _
Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blackshe= ep.org] namens Stefan Sch=E4fer [schaefer@iup.uni-heidelberg.de]
Verzonden: zondag 31 oktober 2010 0:59
Aan: rsgb_lf_group@blacksheep.orgOnderwerp: Re: LF: Re: SBL-3+

Hi Alan,

I want to try an alt= ernative to the BF981 which runs in my current LF
grabber RX. It downconverts 137 kHz to 12 kHz and feeds the soundcard
w= ith this 12 kHz signal. It is running not too bad but i have some
probl= ems with temperature drifting bandpass filters (since weeks) and
have= thrown them out of the Drain-to-Plus path. So, now the setup is
running with a 2 stage RC LPF. I have had some problems with a to high
= 125 kHz level on the soundcard input and have applied a series LC
circu= it for 125 kHz now which reasonably solved the problem. But the LF
nois= e is now just about 10 dB above the soundcard noise, in the
afternoon. There is still a lack of sensitivity. This RX QTH should be
= very well for a grabber antenna but currently the setup is the problem.So i want to try something different, like a DBM. I am not an expert
here and can/have to learn a lot, it seems ;-)

73, Stefan

Am= 31.10.2010 00:41, schrieb Alan Melia:
=A0
Hi Stefan why a difficult to= get mixer?? the IF port on most DBMs is DC
coupled so feed the siganl= in there and (i presume) mix up ?? Or is the
RF/LO response still too high on the easily available ones?

Alan G3= NYK
----- Original Message -----
From: "Stefan Sch=E4fer"&= lt;sch= aefer@iup.uni-heidelberg.de>
To:<r= sgb_lf_group@blacksheep.org>
Sent: Saturday, October 30, 2010 9:= 29 PM
Subject: LF: SBL-3+



=A0 =A0
Dear LF,

I want to try= a LF converter using this mixer. Does anybody know a
(cheep!) distribu= tor in Germany or EU for 1...3 pieces of it? I've just
found one where it costs about 40 Euro and this is to much!!

73, St= efan/DK7FC


=A0 =A0 =A0
=A0 =A0


--002215048a439688cc0493e6cbeb--