Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-da01.r1000.mx.aol.com (Internet Inbound) with ESMTP id B4A4638000093; Wed, 2 May 2012 20:28:03 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SPjst-0003eM-BD for rs_out_1@blacksheep.org; Thu, 03 May 2012 01:27:03 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SPjss-0003eD-DW for rsgb_lf_group@blacksheep.org; Thu, 03 May 2012 01:27:02 +0100 Received: from nm16-vm0.bullet.mail.ird.yahoo.com ([77.238.189.192]) by relay1.thorcom.net with smtp (Exim 4.77) (envelope-from ) id 1SPjsp-0005j4-Qk for rsgb_lf_group@blacksheep.org; Thu, 03 May 2012 01:27:01 +0100 Received: from [77.238.189.231] by nm16.bullet.mail.ird.yahoo.com with NNFMP; 03 May 2012 00:26:58 -0000 Received: from [212.82.108.237] by tm12.bullet.mail.ird.yahoo.com with NNFMP; 03 May 2012 00:26:58 -0000 Received: from [127.0.0.1] by omp1002.mail.ird.yahoo.com with NNFMP; 03 May 2012 00:26:58 -0000 X-DKIM-Result: Domain=yahoo.co.uk Result=Good and Known Domain X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 763152.67705.bm@omp1002.mail.ird.yahoo.com Received: (qmail 13555 invoked by uid 60001); 3 May 2012 00:26:58 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.co.uk; s=s1024; t=1336004818; bh=sEnBPEMJwwpwLqu1MPJCzzf55P77tUb2QxzFFPbVhkM=; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=RE6oVmWRZy0ESwDjqXObZk952o+5fvD/LTDkaav7eadIUA5kaJGqSSfwBli3TLFAFc0Z7BH+aAUh9U89G3ar84zqwnIk0ycfYKmDT4m7QKqbj6AFd1JacwAVTc6winzHkQbuxf/NpB2He8QeFnKCuzwEQ8u1lfpfdyXEnZeatl8= DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.co.uk; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=v9JqE4Iygq67D8SBJxGncLNeB2BP9y8Ln8mx/hzMCoqnmKwWM/+K9kNUIN5mtkvKODTYWw8wT0ItfSuRxfvB439WLD5mLuEMugJruxBFtpMBUI/gEk40FiNJlXme8gl4KoUvVthiiIcHc8ZwfcVcpqUfX3IJhRJYP7WI++yXESc=; X-YMail-OSG: TDT1X9MVM1nJk7PhhedqxDWCbyxKlRDIH1pCI475Vtkabag JEn.d0WYp8pjrAlJaOt895hCzt0zdK0BJSm40AoMPDzYqEvkfIOVisjHYyVu 7jp27kPRZqW6GawlcZEKO6x7rdCS4gHBo7kumHucXss2YPoE0YrNqm7efUob rRUyhmN_IjpkHS8LW6tt39K5COtRg1ejQz.oeCADUSHnMmO72bF96y275jE9 jwwuDPHKK6zMrtTc_aKON1RLeaF3x4jWPD2wl86.pAGGeMPoc._V097iCsw4 gTYEOW0HEs58I90eaEosZ6ihzKi6jJX19qMaKDuB7woUEE9oTbwsHnYf6bMn hpt.2LJpl2txtMygSYhwYsmS0apu80BaHZSVFkVfrwy0ilpDdqcFrKQyU.PI V8kHOx2.2HKBR48ZU5dQ7ouRbNbDDQI_IsZw2RTXLcvspAlqet0Ufd20dzD1 8ys49qEEv0RJkid.ttCYX4cHi3yL7DmsHCHysHHuqjKCUWR2_sk7xzbXzjuv kF5Vu_1sljOxh2wYQGjEgbawpytAHvyWzDPO7o5NrQ1EVk.7fJGvuN8hJucX aL_S3szjhWYfqTe4QXCuLhnuznTn9 Received: from [86.164.68.92] by web171602.mail.ir2.yahoo.com via HTTP; Thu, 03 May 2012 01:26:58 BST X-Mailer: YahooMailWebService/0.8.117.340979 References: <4FA04D47.6070701@iup.uni-heidelberg.de> <006f01cd27ed$47cca9e0$4001a8c0@lark> Message-ID: <1336004818.4361.YahooMailNeo@web171602.mail.ir2.yahoo.com> Date: Thu, 3 May 2012 01:26:58 +0100 (BST) From: M0FMT To: "rsgb_lf_group@blacksheep.org" In-Reply-To: <006f01cd27ed$47cca9e0$4001a8c0@lark> MIME-Version: 1.0 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 all I would not rate The LF Experimenters Handbook publications that highly for a beginner. 1/ Some of the schematics have errors and omissions. 2/ The TX schematics call out "Unobtainium". Such as ferrites that probably only available to "professionals" and some of the IC devices that were only available to 1000up buyers. 3/ A lack of clear circuit description in some cases. No clear description of Class D and E etc, operation and in one case I think a positively misleading description of power FET feeding requirements for best efficiency. Also the deficiencies of the first issue were carried over into the second edition. Having bought both I felt a little disappointed in that the missing information in the PA0 136TX design in the driver stage was not put right in the second edition......... I am not the only person to have been disappointed by this. To some extent these publications are produced with an assumption of a certain amount of pre-knowledge. To the expert in the field these criticisms are minor but to a constructor and not a designer the missing information and unobtainable components become a show stopper. [...] 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 [77.238.189.192 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (m0fmt[at]yahoo.co.uk) 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: 52d17ee6003fa6763aae891a69410baf Subject: Re: LF: Re: Basic LF understanding Content-Type: multipart/alternative; boundary="1507048413-1264151063-1336004818=:4361" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=HTML_MESSAGE, TO_ADDRESS_EQ_REAL 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-SCORE: 0:2:502398464:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d005.1 ; domain : yahoo.co.uk DKIM : fail x-aol-sid: 3039ac1d40494fa1d1130496 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --1507048413-1264151063-1336004818=:4361 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hi all=0A=A0=0AI would not rate=A0The LF Experimenters Handbook=A0publicati= ons that highly for a beginner.=0A=A0=0A1/=A0Some of the schematics have er= rors and omissions.=0A=A0=0A2/ The TX schematics call out "Unobtainium". Su= ch as ferrites that probably only available to "professionals" and some of = the IC devices that were only available to 1000up buyers.=0A=A0=0A3/ A lack= of clear circuit description in some cases. No clear description of Class = D and E etc,=A0operation and in one case I think a positively misleading de= scription of power FET feeding requirements for best efficiency.=0A=A0=0AAl= so the deficiencies of the first issue were carried over into the second ed= ition. Having bought both I felt a little disappointed in that the missing = information in the PA0 136TX design in the driver stage was not put right i= n the second edition......... I am not the only person to have been disappo= inted by this. =0A=A0=0ATo some extent these publications are=A0produced wi= th an assumption of a=A0certain amount of pre-knowledge.=0A=A0=0ATo the exp= ert in the field these criticisms are minor but to a constructor and not a = designer=A0=0Athe missing information and unobtainable components become a = show stopper.=0A=0ANot only that, there is reference to the design of the D= ecca navigation legacy equipment which there could only be a hand full avai= lable in the country and was irrelevant to the new starter on these LF band= s who could not obtain these pieces of kit or construct them.=0A=A0=0AOne o= f the best and helpful additions to the MF/LF canon (not in the LF handbook= ) was the series of TX designs by Rog=A0GW3UEP who saw the need to avoid "U= nobtainium". His designs are clear, use components obtainable at Maplin and= not a "Magical" ferrite core in sight. Not only that he illustrates his co= nstruction article with typical Oscillographs of the circuit under test so = the constructor can be sure he has got the circuit operating in the correct= mode by reproducing them.=0A=A0=0AI know that if anybody cares to read thi= s=A0it will provoke a backlash. It is not intended to belittle the efforts = of the original authors to who I am grateful to for enthusing me. However a= fter several fruitless attempts to recreate=A0some of the circuits in those= publications I had to go elsewhere to get a better understanding of what I= was trying to make.=0A=A0=0ABuyer beware.=0A=A0=0A73 es GL Pete M0FMT IO91= UX=0A=0A=0A________________________________=0A From: Alan Melia =0ATo: rsgb_lf_group@blacksheep.org =0ASent: Tuesday, 1 May= 2012, 23:29=0ASubject: LF: Re: Basic LF understanding=0A =0AHi Stephan to= be afir anyone starting needs to read Riks pages and if they=0Adont unders= tand just ask. I am not in favour of "nursury" guides as you=0Afinish up wa= sting a lot of time saying well that not really how to do it.=0AThe other s= ources are pre internet and are the early LF sourcebook and the=0ALF exprim= enters guide (by Peter Dodd)=0A=0AThe thing is every one if different, has = different starting knowledge,=0Adifferent locations, with different local c= onditions and QRM. Starting is a=0Amatter of conquoring those or at least r= ecognising them. A read of the=0Awaterfall dispay pages (I cant remember wh= at Rik calls them is an essential=0Astarter) The DSP waterfall is so useful= l for identifying problems it should=0Anot be avoided in the early satges a= nd even if the QRM is bad and the=0Areceiver deaf it will probably aid you = to hear something. One of the most=0Adifficult part is finding a receiver t= hat has any performance down there out=0Aof the standard Amateur range. A l= ot that advertise they go from DC to=0A1300MHz are very deaf below 500kHz o= r even 2MHz.=0A=0AIf a newcommer wants something less daunting than the occ= asional maths in=0ARik's pages them=A0 Dave Picks pages at http://wireless.= org.uk/geton136.htm=0Aare to be recommended. Dave being one of the true pio= neers of LF in the UK.=0A=0AAlan G3NYK=0A=0A=0A----- Original Message -----= =0AFrom: "Stefan Sch=E4fer" =0ATo: = =0ASent: Tuesday, May 01, 2012 9:53 PM=0ASubj= ect: LF: Basic LF understanding=0A=0A=0A> LF!=0A>=0A> Has someone a very go= od link to basic understanding about LF? I mean the=0A> LF amateur radio st= uff, all which one has to learn when starting rx-wise=0A> in our hobby! May= be some ideas and examples, a good compliation. Not to=0A> complex and focu= sing on 137 kHz amateur radio?=0A> For newcomers in the "LF-transmit-world"= i recommend ON7YD's page=0A> http://www.strobbe.org/on7yd/136ant/=0A> Is t= here maybe something for receive newcomers?=0A>=0A> A collection of some li= nks may help as well...=0A>=0A> Thanks in advance.=0A>=0A> 73, Stefan/DK7FC= =0A> --1507048413-1264151063-1336004818=:4361 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Hi all
 
I would not rate The LF Experim= enters Handbook publications that highly for a beginner.
<= div> 
1/ Some of the schematics have= errors and omissions.
 
2/ The TX schematics call out = "Unobtainium". Such as ferrites that probably only available to "profession= als" and some of the IC devices that were only available to 1000up buyers.<= /span>
 
3/ A lack of clear cir= cuit description in some cases. No clear description of Class D and E etc,&= nbsp;operation and in one case I think a positively misleading description = of power FET feeding requirements for best efficiency.
 
Also the = deficiencies of the first issue were carried over into the second edition. = Having bought both I felt a little disappoint= ed in that the missing information in the PA0 136TX design in= the driver stage was not put right in the second edition......... I am not= the only person to have been disappointed by this.
 
= To some extent these publications are produced with an assumption of a=  certain amount of pre-knowledge.
 =
To the expert in the field these <= span>criticisms are minor but to a constructor and not a desi= gner 
the missing information and unobtainable compon= ents become a show stopper.
 
Not only that, there is reference to the design of the Decca navigation legacy equipment = which there could only be a hand full available in the country and was irrelevant to the new starter on t= hese LF bands who could not obtain these pieces of kit or construct them.
 
One of the best and helpful additions to the MF/L= F canon (not in the LF handbook) was the series of TX designs by Rog G= W3UEP who saw the need to avoid "Unobtainium". His designs are clear, use c= omponents obtainable at Maplin and not a "Magical" ferrite core in sight. N= ot only that he illustrates his construction= article with typical Oscillographs of the circuit under test= so the constructor can be sure he has got the circuit operating in the cor= rect mode by reproducing them.
 
I know that if an= ybody cares to read this it will provoke a backlash. It is not intended to belittle the efforts of the original authors to who I am grate= ful to for enthusing me. However after several fruitless attempts to recrea= te some of the circuits in those publications I had to go elsewhere to get a better understanding of= what I was trying to make.
 
Buyer beware.
<= div> 
73 es GL Pete M0FMT IO91UX
From: Alan Mel= ia <alan.melia@btinternet.com>
To: rsgb_lf_group@blacksheep.org
Se= nt: Tuesday, 1 May 2012, 23:29
Subject: LF: Re: Basic LF understanding

Hi Stephan to be afir anyone starting needs to read Riks pages and = if they
dont understand just ask. I am not in favour of "nursury" guides= as you
finish up wasting a lot of time saying well that not really how = to do it.
The other sources are pre internet and are the early LF source= book and the
LF exprimenters guide (by Peter Dodd)

The thing is e= very one if different, has different starting knowledge,
different locat= ions, with different local conditions and QRM. Starting is a
matter of c= onquoring those or at least recognising them. A read of the
waterfall di= spay pages (I cant remember what Rik calls them is an essential
starter)= The DSP waterfall is so usefull for identifying problems it should
not be avoided in the early satges and even if the QRM is bad an= d the
receiver deaf it will probably aid you to hear something. One of t= he most
difficult part is finding a receiver that has any performance do= wn there out
of the standard Amateur range. A lot that advertise they go= from DC to
1300MHz are very deaf below 500kHz or even 2MHz.

If a= newcommer wants something less daunting than the occasional maths in
Ri= k's pages them  Dave Picks pages at http://wireless.org.uk/geton136.htm
= are to be recommended. Dave being one of the true pioneers of LF in the UK.=

Alan G3NYK


----- Original Message -----
From: "Stefa= n Sch=E4fer" <Stefan.Schaefer@iup= .uni-heidelberg.de>
To: <rsgb_lf_group@blacksheep.org>
Sent: Tuesday, M= ay 01, 2012 9:53 PM
Subject: LF: Basic LF understanding


> = LF!
>
> Has someone a very good link to basic understanding abo= ut LF? I mean the
> LF amateur radio stuff, all which one has to lear= n when starting rx-wise
> in our hobby! Maybe some ideas and examples= , a good compliation. Not to
> complex and focusing on 137 kHz amateu= r radio?
> For newcomers in the "LF-transmit-world" i recommend ON7YD= 's page
> http://www.strobbe.org/on7yd/136ant/
> Is there maybe som= ething for receive newcomers?
>
> A collection of some links ma= y help as well...
>
> Thanks in advance.
>
> 73, St= efan/DK7FC
>




=20
--1507048413-1264151063-1336004818=:4361--