Return-Path: Received: from mtain-mh02.r1000.mx.aol.com (mtain-mh02.r1000.mx.aol.com [172.29.96.214]) by air-df01.mail.aol.com (v127_r1.1) with ESMTP id MAILINDF012-5ee34b8a944b24c; Sun, 28 Feb 2010 11:05:31 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mh02.r1000.mx.aol.com (Internet Inbound) with ESMTP id C7EE538000287; Sun, 28 Feb 2010 11:05:29 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NllcY-00063Q-0w for rs_out_1@blacksheep.org; Sun, 28 Feb 2010 16:03:54 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NllcX-00063C-4B for rsgb_lf_group@blacksheep.org; Sun, 28 Feb 2010 16:03:53 +0000 Received: from out1.ip06ir2.opaltelecom.net ([62.24.128.242]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NllcU-0008Kd-TJ for rsgb_lf_group@blacksheep.org; Sun, 28 Feb 2010 16:03:53 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Av8EAMkiiktOkz18/2dsb2JhbACNGAOCHYtkc7ghhHsE X-IronPort-AV: E=Sophos;i="4.49,556,1262563200"; d="scan'208,217";a="451872307" Received: from unknown (HELO your91hoehfy9g) ([78.147.61.124]) by out1.ip06ir2.opaltelecom.net with SMTP; 28 Feb 2010 16:02:10 +0000 Message-ID: <000d01cab88f$63d380c0$0301a8c0@your91hoehfy9g> From: "mal hamilton" To: References: <38A51B74B884D74083D7950AD0DD85E82A1B21@File-Server-HST.hst.e-technik.tu-darmstadt.de> <8F98AB84B99B4DC1BBD55E264D6FC983@Black> Date: Sun, 28 Feb 2010 16:02:12 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: Re: Re: VLF TX experiments this sunday Content-Type: multipart/alternative; boundary="----=_NextPart_000_000A_01CAB88F.63873580" 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 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-sid: 3039ac1d60d64b8a94497065 X-AOL-IP: 193.82.116.20 ------=_NextPart_000_000A_01CAB88F.63873580 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Pse qsp to Stefan to SHOUT from his hill top and face DOWN wind for an= extra 23 dB. If all 9 DREAMERS face his direction records could be br= oken without the KITE,=20 Do not break WIND to avoid QRM during the listening period. G3KEV ----- Original Message -----=20 From: Markus Vester=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Sunday, February 28, 2010 12:48 PM Subject: LF: Re: VLF TX experiments this sunday Dear LF, Stefan DK7FC just called me on the phone. He asked me to inform the= group that because of much heavier winds than expected, he will not= be able to transmit from the kite antenna today. He also mentioned th= at the output matching of his PA (a converted SMPS circuit) will requi= re some more work. Kind regards, Markus (DF6NM) ----- Original Message -----=20 From: Stefan Sch=E4fer=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Saturday, February 27, 2010 3:33 PM Subject: LF: VLF TX experiments this sunday becomes more probably Dear LF group,=20 =20 Tomorrow, the wind forecast is excellent! See http://www.windfinde= r.com/forecast/frankfurt It is almost to much wind but i have the new kite braid with a str= enght of 500kg... So the antenna will be in a high angle and stable fo= r tests. That is the first positive news. =20 Yesterday i got such a air coil. It has not 85mH but even about 10= 0mH but It's Q is bad at 8,9kHz, just about 38. Anyway, i will easily= handle 20kV rms. This will be the maximum voltage on my single wire.= There are several possibilities to increase the maximum antenna volta= ge, well known and applied in the high voltage power fields but this= may be very difficult at a kite antenna. So i will start with a first= test at only 20kV, if the PA will give a proper power ;-) =20 That coil is very heavy, about 50kg, really no fun to carry that= and there are better ways to realisethat. But it is available i get= the chance to resonate that 100m vertical at 8,9kHz. I tried to reson= ate it in the living room of my parents since it it to heavy to carry= it in my room in the first floor ;-) It was successfully resonated wi= th 6x22nF/6kV plus a lower voltage C in series, about 33nF/2kV and a= DDS VFO with a sinus output, loosely coupled by another air coil (in= this way i will be able to make a transformation of the resonated loo= p!(varying the coupling)). The 8,9kHz are well audible so i am excited= how the antenna and coil will sound when some 100W applied;-) =20 The last problem is the PA since it is not yet available. I will= try to built it today or tomorrow in the morning but i have also to= spend some time with my YL. I hope that can be arranged... =20 On the hill i have no internet but i will at least inform Markus/D= F6NM to give those who are interested a information here... =20 I have to go now, and will inform you... =20 73, Stefan/DK7FC ________________________________ Von: owner-rsgb_lf_group@blacksheep.org im Auftrag von Alexander= S. Yurkov Gesendet: Sa 27.02.2010 20:37 An: rsgb_lf_group@blacksheep.org Betreff: RE: LF: Fwd: Special Permits for Amateur Radio Operation= below 9kHz? > when back in the mid 90's the initial request for a longwave ama= teur > segment (what later turned out to be 137kHz) was discussed, one= of the > big telecom "bobo's" stated that they saw no harm that amateurs= would > transmit there with max. 1 W EIRP as with that power one wouldn'= t be > able to get any further than the other end of the town. > It turned out a bit different, unless you see the world as one= big town ;-) Rik, after some theoretical estimations done i am absolutely shure= =20 QRSS communications at few 100s km (may be more) is posible on 9= kHz. There is lot of problems on TX side but them to be solvable. Main= problem is high voltage on the TX ANT. I expect 100 - 200 kV is reachable= with some 'tricks' wellknown for power ingeneers. For example one shoul= d avoid free end of a wire with such a voltage. On should use 'protecting= rings' on the ends. With voltage abt 100 kV seems to be posible use not= too high antenna. Seems 20-30 m high well top loaded marconi designed speci= ally for high voltage is adequate. Remember effective height of 60m kite an= tenna used in DK8KW experiment was 30m (if wire was absolutelly vertical= , does it was?). With not too high voltage and not too large ANT capacity= 4.5 km was reached. Another key problem is noise level on this freq. Now= we see huge discrepancy on the noise level got from different sourses. Wh= at is the real noise level is not obvious now. Can it be much lower tim= e to time? Experements to be usefull. Look at DK8KW web side where 4.5= km experiment is described. Waterfall background is too smooth. Where spherics are? This is why i expect RX sensetivity was not as high as posible. One should remember 4.5 km is begining of the wav= e zone on 9 kHz. At distanses more then 4.5 km field decreases not too fa= st with distance. Another critical distance is abt 100 km where 'waveguide= ' propagation starts. At such distances one shold increase TX ANT vo= ltage only in 3 times to reach distance 10 times more. Anyway Stefan's experiment will be very intesesting. And i hope it will be not the= last experiment. Regards, Alexander/RA9MB ------=_NextPart_000_000A_01CAB88F.63873580 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Pse qsp to Stefan to SHOUT from his= hill top and=20 face DOWN wind for an extra 23 dB. If all 9 DREAMERS face his=20 direction records could be broken without the KITE,
Do not break WIND to avoid QRM during= the listening=20 period.
 
G3KEV
 
----- Original Message -----
Sent: Sunday, February 28, 20= 10 12:48=20 PM
Subject: LF: Re: VLF TX exper= iments this=20 sunday

Dear LF,
 
Stefan DK7FC just called me on the= phone. He=20 asked me to inform the group that because of much heavier winds than= expected,=20 he will not be able to transmit from the kite antenna today. He=  also=20 mentioned that the output matching of his PA (a converted= SMPS=20 circuit) will require some more work.
 
Kind regards,
Markus (DF6NM)
 
----- Original Message -----
Sent: Saturday, February 27= , 2010 3:33=20 PM
Subject: LF: VLF TX experim= ents this=20 sunday becomes more probably

Dear LF group,
 
Tomorrow, the wind for= ecast is=20 excellent! See http://www.windfinder.com/forecast/frankfurt
It=20 is almost to much wind but i have the new kite braid with a streng= ht of=20 500kg... So the antenna will be in a high angle and stable for tes= ts. That=20 is the first positive news.
 
Yesterday i got such a ai= r coil. It=20 has not 85mH but even about 100mH but It's Q is bad at 8,9kHz, jus= t about=20 38. Anyway, i will easily handle 20kV rms. This will be the maximu= m voltage=20 on my single wire. There are several possibilities to increase the= maximum=20 antenna voltage, well known and applied in the high voltage power= fields but=20 this may be very difficult at a kite antenna. So i will start with= a first=20 test at only 20kV, if the PA will give a proper power ;-)
 = ;
That=20 coil is very heavy, about 50kg, really no fun to carry that and th= ere are=20 better ways to realisethat. But it is available i get the chance= to resonate=20 that 100m vertical at 8,9kHz. I tried to resonate it in the living= room of=20 my parents since it it to heavy to carry it in my room in the firs= t floor=20 ;-) It was successfully resonated with 6x22nF/6kV plus a lower vol= tage C in=20 series, about 33nF/2kV and a DDS VFO with a sinus output, loosely= coupled by=20 another air coil (in this way i will be able to make a transformat= ion of the=20 resonated loop!(varying the coupling)). The 8,9kHz are well audibl= e so i am=20 excited how the antenna and coil will sound when some 100W=20 applied;-)
 
The last problem is the PA since it is not= yet=20 available. I will try to built it today or tomorrow in the morning= but i=20 have also to spend some time with my YL. I hope that can be=20 arranged...
 
On the hill i have no internet but i will= at least=20 inform Markus/DF6NM to give those who are interested a information= =20 here...
 
I have to go now, and will inform=20 you...
 
73,=20 Stefan/DK7FC

________________________________

Von:= owner-rsg= b_lf_group@blacksheep.org=20 im Auftrag von Alexander S. Yurkov
Gesendet: Sa 27.02.2010 20:3= 7
An:=20 rsgb_lf_grou= p@blacksheep.org
Betreff:=20 RE: LF: Fwd: Special Permits for Amateur Radio Operation below=20 9kHz?



> when back in the mid 90's the initial re= quest for=20 a longwave amateur
> segment (what later turned out to be 13= 7kHz) was=20 discussed, one of the
> big telecom "bobo's" stated that the= y saw no=20 harm that amateurs would
> transmit there with max. 1 W EIRP= as with=20 that power one wouldn't be
> able to get any further than th= e other=20 end of the town.
> It turned out a bit different, unless you= see the=20 world as one big town ;-)

Rik, after some theoretical estim= ations=20 done i am absolutely shure
QRSS communications at few 100s km= (may be=20 more) is posible on 9 kHz.
There is lot of problems on TX side= but them=20 to be solvable. Main problem
is high voltage on the TX ANT. I= expect 100=20 - 200 kV is reachable with
some 'tricks' wellknown for power in= geneers.=20 For example one should avoid
free end of a wire with such a vol= tage. On=20 should use 'protecting rings'
on the ends. With voltage abt 100= kV seems=20 to be posible use not too high
antenna. Seems 20-30 m high well= top=20 loaded marconi designed specially for
high voltage is adequate.= Remember=20 effective height of 60m kite antenna
used in DK8KW experiment= was 30m (if=20 wire was absolutelly vertical, does
it was?). With not too high= voltage=20 and not too large ANT capacity 4.5 km
was reached. Another key= problem is=20 noise level on this freq. Now we see
huge discrepancy on the no= ise level=20 got from different sourses. What is
the real noise level is not= obvious=20 now. Can it be much  lower time to
time? Experements to be= usefull.=20 Look at DK8KW web side where 4.5 km
experiment is described. Wa= terfall=20 background is too smooth. Where
spherics are? This is why i exp= ect RX=20 sensetivity was not as
high as posible. One should remember 4.5= km is=20 begining of the wave zone
on 9 kHz. At distanses more then 4.5= km field=20 decreases not too fast with
distance. Another critical distance= is abt=20 100 km where 'waveguide'
propagation starts. At such distances= one shold=20 increase TX ANT voltage
only in 3 times to reach distance 10 ti= mes more.=20 Anyway Stefan's
experiment will be very intesesting. And i hope= it will=20 be not the=20 last
experiment.

Regards,
Alexander/RA9MB


=

------=_NextPart_000_000A_01CAB88F.63873580--