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[195.171.43.25]) by mx.google.com with ESMTP id p14si2646899wie.14.2013.08.04.08.43.07 for ; Sun, 04 Aug 2013 08:43:07 -0700 (PDT) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1V5zyf-0001Yh-KM for rs_out_1@blacksheep.org; Sun, 04 Aug 2013 16:12:13 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1V5zye-0001YY-Tq for rsgb_lf_group@blacksheep.org; Sun, 04 Aug 2013 16:12:12 +0100 Received: from mta01.eastlink.ca ([24.224.136.30]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1V5zyc-0005dK-99 for rsgb_lf_group@blacksheep.org; Sun, 04 Aug 2013 16:12:11 +0100 Received: from cmgw05.eastlink.ca ([71.7.199.171]) by mta01.eastlink.ca (Oracle Communications Messaging Exchange Server 7u4-21.01 64bit (built Feb 16 2011)) with ESMTP id <0MR000C7N7VSLYK0@mta01.eastlink.ca> for rsgb_lf_group@blacksheep.org; Sun, 04 Aug 2013 12:12:08 -0300 (ADT) Received: from JimPC ([24.224.157.45]) by cmgw05.eastlink.ca with id 8fC61m0020z39E001fC7gN; Sun, 04 Aug 2013 12:12:07 -0300 X-Authority-Analysis: v=2.1 cv=XJAJF2RE c=1 sm=1 tr=0 a=7Vo9aBytTRElHvSpe2g7jw==:117 a=7Vo9aBytTRElHvSpe2g7jw==:17 a=0g5ImgW44TsA:10 a=71nC4Wke_oIA:10 a=r77TgQKjGQsHNAKrUKIA:9 a=9iDbn-4jx3cA:10 a=cKsnjEOsciEA:10 a=i6_WIJnST_-USFn8le4A:9 a=wPNLvfGTeEIA:10 a=pGLkceISAAAA:8 a=F3M5lZpKAAAA:8 a=-lCLr7tfofmWzkCjpuQA:9 a=lN4y9l73i11iyrVe:21 a=_W_S_7VecoQA:10 a=tXsnliwV7b4A:10 a=MSl-tDqOz04A:10 a=wk6s2zzMB60A:10 Message-id: <09E61DED195E43049D9A359EE6958F73@JimPC> From: Jim and Hannelore Fisher To: rsgb_lf_group References: <51FDA127.80500@iup.uni-heidelberg.de> <51FE3D6F.5040001@iup.uni-heidelberg.de> In-reply-to: Date: Sun, 04 Aug 2013 15:12:05 +0000 MIME-version: 1.0 X-Priority: 3 X-MSMail-priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6002.18197 X-MIMEOLE: Produced By Microsoft MimeOLE V6.0.6002.18463 X-Spam-Score: -0.7 (/) 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: At one point in the early 1970s, I as W8KJN was using a balloon-lifted 5/8wl 40M vertical for an RSGB 40M contest (worked really well). I used a war surplus balloon and wire, cutting the wire to 5/8wl and loading it with my tuner on my USAF MARS HT4G (civilian predecessor of BC610). My experience was that the radiating element was somewhat more stable and vertical if the balloon was tethered upwind and the radiating element was nominally vertical. It did sag and bounce a bit in windy conditions. Of course, that requires the space for an upwind anchor site. [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [24.224.136.30 listed in list.dnswl.org] 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: d315c81827f71be07030d900195100c1 Subject: Re: LF: USA issued 68 to 76 kHz band with 10 W ERP Content-type: multipart/alternative; boundary="----=_NextPart_000_09B1_01CE9124.FB352F60" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30,HTML_MESSAGE, MISSING_OUTLOOK_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: 3096 This is a multi-part message in MIME format. ------=_NextPart_000_09B1_01CE9124.FB352F60 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable At one point in the early 1970s, I as W8KJN was using a balloon-lifted = 5/8wl 40M vertical for an RSGB 40M contest (worked really well). I used = a war surplus balloon and wire, cutting the wire to 5/8wl and loading it = with my tuner on my USAF MARS HT4G (civilian predecessor of BC610). My = experience was that the radiating element was somewhat more stable and = vertical if the balloon was tethered upwind and the radiating element = was nominally vertical. It did sag and bounce a bit in windy conditions. = Of course, that requires the space for an upwind anchor site. If I were to try another balloon- or kite-supported antenna I would = repeat that approach. A neighbour's son came by while I was adjusting things and inquired what = I was doing. I replied I was fishing for flying fish (we were by an = inland lake). The neighbour was a ham and came over for the evening and, = with my wife and me, enjoyed a sip by the the glow of the final and the = mercury vapour rectifiers and the lights on the HT4G and R-390A. 73, Jim, VE1JF ----- Original Message -----=20 From: Warren Ziegler=20 To: rsgb_lf_group=20 Sent: Sunday, August 04, 2013 2:02 PM Subject: Re: LF: USA issued 68 to 76 kHz band with 10 W ERP Markus, Stefan, LF, Please keep in mind that 10W represents an upper limit, we are = free to run anything below that! About Quadcopters - the limitation is the life of the battery - = which is on the order of 15 minutes, even if it could lift enough = weight, it wouldn't last long! (The more weight it must lift the higher = the battery drain!) A better solution might be a remote controlled airship (zeppelin) = where the helium supplies the lift and motors provide steering only. 73 Warren K2ORS =20 On Sun, Aug 4, 2013 at 7:39 AM, Stefan Sch=E4fer = wrote: Hi Markus,=20 Am 04.08.2013 09:46, schrieb Markus Vester:=20 Stefan, 10 W ERP is not that hard - anyone who can radiate 80 W = ERP on 136 will be able to do 10 W on half the frequency ;-)) Oh yes indeed. The radiation resistance of the wire is about 1/4 and = the needed L is about 4x, so the coil losses will be 4x higher too. The = ground losses may drop a bit. Then it depends on the ratio of coil = losses to ground losses. So 80W is realistic :-) I don't know anything about LF propagation on that band. Is it much = different to 2200m? And what are the distance records?=20 Yesterday night a friend showed me his new GPS-stabilized = quadrocopter. It's stunning how it could just about be parked in midair, = despite some lateral winds. Seems that would make a great antenna = carrier! Not all of the neighbour's seemed to enjoy it as much as we = did...=20 MOST interesting! Did you ask him what the weight can be lifted? And = will it still be stable then? Is it expensive? Do you fear some EMC = problems? (The topic should be discussed in a new subject then) 73, Stefan/DK7FC Best 73, Markus (DF6NM) --=20 73 Warren K2ORS WD2XGJ=20 WD2XSH/23 WE2XEB/2 WE2XGR/1 ------=_NextPart_000_09B1_01CE9124.FB352F60 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
At one point in the early 1970s, I as = W8KJN was=20 using a balloon-lifted 5/8wl 40M vertical for an RSGB 40M contest = (worked really=20 well). I used a war surplus balloon and wire, cutting the wire to 5/8wl = and=20 loading it with my tuner on my USAF MARS HT4G (civilian = predecessor of=20 BC610). My experience was that the radiating element was somewhat more = stable=20 and vertical if the balloon was tethered upwind and the radiating = element was=20 nominally vertical. It did sag and bounce a bit in windy = conditions. Of=20 course, that requires the space for an upwind anchor site.
 
If I were to try another balloon- or = kite-supported=20 antenna I would repeat that approach.
 
A neighbour's son came by while I was = adjusting=20 things and inquired what I was doing. I replied I was fishing for flying = fish=20 (we were by an inland lake). The neighbour was a ham and came over for = the=20 evening and, with my wife and me, enjoyed a sip by the the glow of = the=20 final and the mercury vapour rectifiers and the lights on the HT4G and=20 R-390A.
 
73,
 
Jim, VE1JF
----- Original Message -----
From:=20 Warren = Ziegler=20
Sent: Sunday, August 04, 2013 = 2:02=20 PM
Subject: Re: LF: USA issued 68 = to 76 kHz=20 band with 10 W ERP

Markus, Stefan, LF,

      Please keep in mind that 10W represents an = upper=20 limit, we are free to run anything below that!

     About Quadcopters - the limitation is the = life of the=20 battery - which is on the order of 15 minutes, even if it could lift = enough=20 weight, it wouldn't last long! (The more weight it must lift the = higher the=20 battery drain!)

     A better solution might be a remote = controlled=20 airship (zeppelin) where the helium supplies the lift and motors = provide=20 steering only.


73 Warren K2ORS

  


On Sun, Aug 4, 2013 at 7:39 AM, Stefan = Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de> = wrote:
Hi Markus,

Am = 04.08.2013=20 09:46, schrieb Markus Vester:=20
 
Stefan, 10 W ERP is not that hard - anyone = who can=20 radiate 80 W ERP on 136 will be able to do 10 W on half the = frequency=20 ;-))
Oh yes indeed. The radiation = resistance=20 of the wire is about 1/4 and the needed L is about 4x, so the coil = losses=20 will be 4x higher too. The ground losses may drop a bit. Then it = depends on=20 the ratio of coil losses to ground losses. So 80W is realistic = :-)

I=20 don't know anything about LF propagation on that band. Is it much = different=20 to 2200m? And what are the distance records?

Yesterday night a friend showed = me his new=20 GPS-stabilized quadrocopter. It's stunning how it could just = about be=20 parked in midair, despite some lateral winds. Seems that would = make a=20 great antenna carrier! Not all of the neighbour's seemed=20 to enjoy it as much as we did...=20
MOST interesting! Did you ask him = what the=20 weight can be lifted? And will it still be stable then? Is it = expensive? Do=20 you fear some EMC problems? (The topic should be discussed in a new = subject=20 then)

73, Stefan/DK7FC

 
Best 73,
Markus=20 (DF6NM)



--
73 Warren K2ORS
        =  =20       WD2XGJ
          =  =20     WD2XSH/23
            =  =20   WE2XEB/2
              =  =20 WE2XGR/1

 
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