X-GM-THRID: 1207413632619629696 X-Gmail-Labels: rsgb lf X-Gmail-Received: c8d961b69fb6319bc554136544ce4f27f4daa279 Delivered-To: daveyxm@gmail.com Received: by 10.64.249.17 with SMTP id w17cs247042qbh; Wed, 28 Jun 2006 14:32:36 -0700 (PDT) Received: by 10.48.162.8 with SMTP id k8mr990030nfe; Wed, 28 Jun 2006 14:32:36 -0700 (PDT) Return-Path: Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mx.gmail.com with ESMTP id l32si709597nfa.2006.06.28.14.32.35; Wed, 28 Jun 2006 14:32:36 -0700 (PDT) Received-SPF: neutral (gmail.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Fvhc9-0005On-O6 for rs_out_1@blacksheep.org; Wed, 28 Jun 2006 22:30:25 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Fvhc9-0005Oe-8t for rsgb_lf_group@blacksheep.org; Wed, 28 Jun 2006 22:30:25 +0100 Received: from imo-d20.mx.aol.com ([205.188.139.136]) by relay1.thorcom.net with esmtp (Exim 4.62) (envelope-from ) id 1Fvhc6-0000gf-Dt for rsgb_lf_group@blacksheep.org; Wed, 28 Jun 2006 22:30:25 +0100 Received: from G4gvw@aol.com by imo-d20.mx.aol.com (mail_out_v38_r7.5.) id l.548.10ae09f (48624) for ; Wed, 28 Jun 2006 17:30:13 -0400 (EDT) From: G4gvw@aol.com Message-ID: <548.10ae09f.31d44ee5@aol.com> Date: Wed, 28 Jun 2006 17:30:13 EDT To: rsgb_lf_group@blacksheep.org MIME-Version: 1.0 X-Mailer: 9.0 SE for Windows sub 5012 X-Spam-Flag: NO X-Spam-Score: -1.1 (-) X-Spam-Report: autolearn=disabled,AWL=-1.350,HTML_30_40=0.056,HTML_MESSAGE=0.001,NO_REAL_NAME=0.178 Subject: Re: LF: Sparc transmitter Content-Type: multipart/alternative; boundary="-----------------------------1151530213" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.3 required=5.0 tests=HTML_MESSAGE,NO_REAL_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: 6999 -------------------------------1151530213 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit A couple of years ago I old on ebay a portable transmitter and receiver set of WW1 era which comprised a "spark transmitter" which was simply a doorbell- type buzzer powered by a 4.5volt "cycle lamp" battery feeding into a tapped inductance coupled to a couple of turns intended to be fed to "antenna" and " earth ("ground" to you yanks). The rx side of this transceiver was nothing more than a "cats whisker" type receiver coupled to the same inductor combination. My researches suggested that this "transceiver" had been designed for clandestine use behind enemyloines during the 1914 - 1918 war in europe. Because I had the facilities ( and also,it has to be said; because it "was there"), I fired this combo up into all manner of loads and watched the results on a speccy. Man, I can tell you it was a frightening display! Unless you provided an elaborate tuned circuit the spectrum was that of a comb generator from almost DC to light ! I have to say that the rx performance left something to be desired but I learned something very important! Somebody had to be first ! Somebody had to have the balls to design and make a "trancseiver". it probably doesn't matter very much who was first but my pleasure and learning for a few weeks was derived from this concept! What it taught me was that there is, in reality, nothing new in radio science or perhaps in any science or engineering endeavour! What there is are a list of truths waiting to be discovered and explained to a following group of researchers. -------------------------------1151530213 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
A couple of years ago I old on ebay a portable transmitter and receiver= set=20 of WW1 era which comprised a "spark transmitter" which was simply a doorbell= -=20 type buzzer powered by a 4.5volt "cycle lamp" battery feeding into a tapped=20  inductance coupled to a couple of turns intended to be fed to "antenna= "=20 and " earth ("ground" to you yanks). The rx side of this transceiver was not= hing=20 more than a "cats whisker" type receiver coupled to the same inductor=20 combination.
My researches suggested that this "transceiver" had been designed for=20 clandestine use behind enemyloines during the 1914 - 1918 war in europe.
 
Because I had the facilities ( and also,it has to be said; because it "= was=20 there"), I fired this combo up into all manner of loads and watched the resu= lts=20 on a speccy.
 
Man, I can tell you it was a frightening display!
 
Unless you provided an elaborate tuned circuit the spectrum was that of= a=20 comb generator from almost DC to light !
 
I have to say that the rx performance left something to be desired but=20= I=20 learned something very important!
 
Somebody had to be first ! Somebody had to have the balls to design and= =20 make a "trancseiver".
 
it probably doesn't matter very much who was first but my pleasure and=20 learning for a few weeks was derived from this concept!
 
What it taught me was that there is, in reality, nothing new in radio=20 science or perhaps in any science or engineering endeavour!  What there= is=20 are a list of truths waiting to be discovered and explained to a following g= roup=20 of researchers.
 
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