Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, HTML_MESSAGE,RCVD_IN_DNSWL_MED,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mailn.lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id uB5ATMN2007973 for ; Mon, 5 Dec 2016 11:29:23 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1cDqRU-0006mh-TV for rs_out_1@blacksheep.org; Mon, 05 Dec 2016 10:24:16 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1cDqRU-0006mW-5R for rsgb_lf_group@blacksheep.org; Mon, 05 Dec 2016 10:24:16 +0000 Received: from gmy2-mh867.smtproutes.com ([94.186.192.196]) by relay1.thorcom.net with esmtp (Exim 4.87) (envelope-from ) id 1cDqRR-0006X7-8w for rsgb_lf_group@blacksheep.org; Mon, 05 Dec 2016 10:24:15 +0000 X-Katharion-ID: 1480933437.49127.gmy2-mh867 Received: from servigilant.vigilant.es ([87.216.178.132]) by gmy2-mh867.smtproutes.com [(94.186.192.196)] with ESMTP via TCP (TLSv1/TLS_RSA_WITH_AES_256_CBC_SHA); 05 Dec 2016 10:23:57 +0000 Received: from servigilant.vigilant.local ([fe80::c40d:8140:d722:5448]) by servigilant.vigilant.local ([fe80::c40d:8140:d722:5448%16]) with mapi id 14.03.0123.003; Mon, 5 Dec 2016 11:23:53 +0100 From: =?iso-8859-1?Q?VIGILANT_Luis_Fern=E1ndez?= To: "rsgb_lf_group@blacksheep.org" Thread-Topic: Finally 100 mA on 2.97 kHz Thread-Index: AQHSToA7fHL5gs8rBkG+z6z0kd9Pc6D5JOlA Date: Mon, 5 Dec 2016 10:23:52 +0000 Message-ID: <579355A36AEE9D4FA555C45D556003AB5D87FD5B@servigilant.vigilant.local> In-Reply-To: <5844957F.3070004@posteo.de> Accept-Language: es-ES, en-US Content-Language: es-ES X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [192.168.0.2] MIME-Version: 1.0 X-Scan-Signature: c1dcf088149efa0360827745859da381 Subject: LF: RE: Finally 100 mA on 2.97 kHz Content-Type: multipart/alternative; boundary="_000_579355A36AEE9D4FA555C45D556003AB5D87FD5Bservigilantvigi_" 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 2.75 Status: O X-Status: X-Keywords: X-UID: 9716 --_000_579355A36AEE9D4FA555C45D556003AB5D87FD5Bservigilantvigi_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Congratulations for this great step ahead Stefan !!! :-) >From your hard work and impressive pictures it is quite clear that ULF is v= eeeeeery hard compared to LF/MF and every Hz down there becomes harder and = harder Amazing work and beautiful construction. My best wishes for the results in = your tests Please keep posting. May be not many will said anything but we are all watc= hing ....mouth wide open ;-) 73 de Luis EA5DOM ________________________________ De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blackshe= ep.org] En nombre de DK7FC Enviado el: domingo, 04 de diciembre de 2016 23:15 Para: rsgb_lf_group@blacksheep.org Asunto: ULF: Finally 100 mA on 2.97 kHz ULF, It was a clear, cold and sunny day again and finally i was testing the new = large 2.97 kHz coil on the roof: https://dl.dropboxusercontent.com/u/198820= 28/ULF/20161204_153126.jpg Not a good idea on MF or LF, but on ULF is can be a good idea to put a resi= stor in series to the coil. I put 500 Ohm in series. This helps to attenuat= e eventual HV transients, makes the resonance curve a bit flatter, so the p= eak is easier to hold. 500 Ohm and 0.1 A, that just a loss of 5W, quite affordable. https://dl.dro= pboxusercontent.com/u/19882028/ULF/20161204_153113.jpg Unfortunetely i found that the actual resonance region is adjustable from 2= 993...3130 Hz. So the inductance is still to low :-( I've been quite sure t= hat my antenna replacement capacity for resonance tests in the shack has th= e right value. So maybe other effects like an additional capacitive load by= the things standing arround in the shack? Or a different behaviour of the = residual antenna + frozen ground capacity on 2970 Hz? At least it was possible to get 100 mA anyway, just by applying some more v= oltage to the antenna. The PA is now running at 20V and less than 1A, most = of that are PA- and transformer losses. Anyway i have 12 kV on the antenna!= That's ULF! I was planning to bring the coil down to the shack anyway, after the 65km e= xperiment which will start in a few days i think. Then i can add more turns= to come closer to 2970 Hz. With 70 uOhm radiation resistance the resulting ERP is now entering the mic= rowatt range: 1.2 uW on the 101km band. A stable carrier at 100 mA was sent from 12:50 UTC to 14:24 UTC. I tried to measure the antenna current with a true rms digital multimeter, = shielded by aluminium foil, measuring on high potential. But the measuremen= t was wrong anyway. The permanent installed analog amperemeter and SpecLab = gave a correct measurement. Tomorrow i will check the antenna current measu= rement on high potential with a calibrated analog amperemeter. For the 65km experiment i want to transmit some DFCW-12000 again as well as= an EbNaut message. The RX site will be in JN39VH :-) 73, Stefan --_000_579355A36AEE9D4FA555C45D556003AB5D87FD5Bservigilantvigi_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Congratulations for this great st= ep ahead Stefan !!! :-)
 
From your hard work and impressiv= e pictures it is quite clear that ULF is veeeeeery hard compared to LF/MF a= nd every Hz down there becomes harder and harder
Amazing work and beautiful constr= uction. My best wishes for the results in your tests
 
Please keep posting. May be not m= any will said anything but we are all watching ....mouth wide open ;-)
 
73 de Luis
EA5DOM

De: owner-rsgb_lf_group@blacksheep.= org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de DK7FC
Enviado el: domingo, 04 de diciembre de 2016 23:15
Para: rsgb_lf_group@blacksheep.org
Asunto: ULF: Finally 100 mA on 2.97 kHz

ULF,

It was a clear, cold and sunny day again and finally i was testing the new = large 2.97 kHz coil on the roof: https://dl.dropboxusercontent.com/u/19882028/ULF/20161204_153126.jpg
Not a good idea on MF or LF, but on ULF is can be a good idea to put a resi= stor in series to the coil. I put 500 Ohm in series. This helps to attenuat= e eventual HV transients, makes the resonance curve a bit flatter, so the p= eak is easier to hold.
500 Ohm and 0.1 A, that just a loss of 5W, quite affordable. https://dl.dropboxusercontent.com/u/19882028/ULF/20161204_153113.jpg
Unfortunetely i found that the actual resonance region is adjustable from 2= 993...3130 Hz. So the inductance is still to low :-( I've been quite sure t= hat my antenna replacement capacity for resonance tests in the shack has th= e right value. So maybe other effects like an additional capacitive load by the things standing arround in the s= hack? Or a different behaviour of the residual antenna +  frozen g= round capacity on 2970 Hz?
At least it was possible to get 100 mA anyway, just by applying some more v= oltage to the antenna. The PA is now running at 20V and less than 1A, most = of that are PA- and transformer losses. Anyway i have 12 kV on the antenna!= That's ULF!
I was planning to bring the coil down to the shack anyway, after the 65km e= xperiment which will start in a few days i think. Then i can add more turns= to come closer to 2970 Hz.

With 70 uOhm radiation resistance the resulting ERP is now entering the mic= rowatt range: 1.2 uW on the 101km band.

A stable carrier at 100 mA was sent from 12:50 UTC to 14:24 UTC.

I tried to measure the antenna current with a true rms digital multimeter, = shielded by aluminium foil, measuring on high potential. But the measuremen= t was wrong anyway. The permanent installed analog amperemeter and SpecLab = gave a correct measurement. Tomorrow i will check the antenna current measurement on high potential with a cali= brated analog amperemeter.

For the 65km experiment i want to transmit some DFCW-12000 again as well as= an EbNaut message. The RX site will be in JN39VH :-)

73, Stefan


--_000_579355A36AEE9D4FA555C45D556003AB5D87FD5Bservigilantvigi_--