Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id w5TG1EOY029739 for ; Fri, 29 Jun 2018 18:01:15 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1fYvck-0004Uj-PH for rs_out_1@blacksheep.org; Fri, 29 Jun 2018 16:47:50 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1fYvci-0004Ua-45 for rsgb_lf_group@blacksheep.org; Fri, 29 Jun 2018 16:47:48 +0100 Received: from smtp-out-5.talktalk.net ([62.24.135.69]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91_59-0488984) (envelope-from ) id 1fYvcf-0003Xp-0Q for rsgb_lf_group@blacksheep.org; Fri, 29 Jun 2018 16:47:46 +0100 Received: from mal ([2.98.120.233]) by smtp.talktalk.net with SMTP id YvccfJ45SdJAeYvccf0chY; Fri, 29 Jun 2018 16:47:44 +0100 X-DKIM-Result: Domain=talktalk.net Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=talktalk.net; s=cmr1711; t=1530287264; bh=V0A/yNUIziBbK7brv5GhLILwy4TRvWaNMxcb9ms3x9Q=; h=From:To:References:In-Reply-To:Subject:Date; b=DjLnGx6mcx48CYsJTHR3fPtKYlzR/uaRwdgPplkSYm81DxnHzUUlmwAo8wil8x48j BLZ247jjNCue0IIZGZE2HL/JUKF8Bu0SHkNGMN+IRQfieIktjRem1EflbSdyfTd7tp JVAvdJAUjOuJMbbG7sxA4HROhmUkgYTCedL44bzg= X-Originating-IP: [2.98.120.233] X-Spam: 0 X-OAuthority: v=2.3 cv=V8BTL9vi c=1 sm=1 tr=0 a=D6bIHr++jcLTNa5lydkfVQ==:117 a=D6bIHr++jcLTNa5lydkfVQ==:17 a=r77TgQKjGQsHNAKrUKIA:9 a=wV9FcBFsAAAA:8 a=nN7BH9HXAAAA:8 a=pGLkceISAAAA:8 a=cQf-JB_omLvXrWRbq-EA:9 a=QEXdDO2ut3YA:10 a=F3M5lZpKAAAA:8 a=6U50XVj74ko8ybKQkh0A:9 a=RDjsCkQwyBc37gS2:21 a=_W_S_7VecoQA:10 a=S9tSBiJD-_FMqjcyfT7e:22 a=slCku8JSH3TyizEDQ3pD:22 Message-ID: From: To: References: <319563372.20180628161811@gmail.com> <5B3512D8.7080006@posteo.de> <8410734267.20180628200411@gmail.com> <062AA646-1868-4A2E-8974-0B22C24248CB@talktalk.net> In-Reply-To: Date: Fri, 29 Jun 2018 16:47:42 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 16.4.3528.331 X-MimeOLE: Produced By Microsoft MimeOLE V16.4.3528.331 X-CMAE-Envelope: MS4wfFOgNwYCosqceFxeFpwRl9byzvA+dFo1yv7ukgafx2yNRjUTUbMf3UFECfHTUwj0umISCRiKezHU04sqpNFlGOjgJ04g4IzBavJ3+PWw73+4KoZTO/qP NU2w3TRo9INprTYlm2pEThm2J2PFnRLVhJIKSDnvqb09Zdc84AqlyI1G X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: If you cannot hear or see the signals on the band of interest you cannot communicate, therefore it is important also to have an efficient RECEIVE system An efficient Antenna system is very important for both TX and RX especially with low level amateur radio signals . I would adopt a different approach if I wanted to listen on two separate receivers simultaneously to two different amateur bands. I would use two separate Antennas each one resonated on the band of interest, in fact I do this for MF/160 and MF/630 g3kev [...] 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 [62.24.135.69 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 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: c7a664e36c9ca637ce420897bb72a08a Subject: LF: Re: Can I match 2 frequencies with one loading coil? Content-Type: multipart/alternative; boundary="----=_NextPart_000_001F_01D40FC8.E60BDD00" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.4 required=5.0 tests=HTML_30_40, HTML_FONTCOLOR_UNSAFE,HTML_FONT_BIG,HTML_MESSAGE,MISSING_OUTLOOK_NAME, 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 This is a multi-part message in MIME format. ------=_NextPart_000_001F_01D40FC8.E60BDD00 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable If you cannot hear or see the signals on the band of interest you cannot = communicate, therefore it is important also to have an efficient = RECEIVE system An efficient Antenna system is very important for both TX and RX = especially with low level amateur radio signals . I would adopt a different approach if I wanted to listen on two separate = receivers simultaneously to two different amateur bands. I would use two separate Antennas each one resonated on the band of = interest, in fact I do this for MF/160 and MF/630=20 g3kev =20 From: Andy Talbot=20 Sent: Friday, June 29, 2018 6:53 AM To: LineOne=20 Subject: Re: LF: Can I match 2 frequencies with one loading coil? Mal ... Did you not read the requirement properly? It was for RECEIVE only. So loss is of no consequence AND he wants to listen on two receivers simultaneously, so switching is not = an option. Andy=20 www.g4jnt.com On 28 June 2018 at 22:16, Mal Hamilton wrote: Andy Your method too lossy and complicated, interaction etc Use one coil for each band and switch between them for the desired=20 Band=20 G3KEV On 28 Jun 2018, at 20:32, Andy Talbot wrote: Try this, but you'll have to adjust iteratively:=20 Bands referred to as LF and MF First make your LF loading coil so it resonates the antenna as it = stands. Now make an MF loading coil. The problem is that t=3Dwhen = both are connected to the antenna teh lower value MF one shunts teh LF. = So add series C to the MF one to make a series tuned circuit, increasing = the L to keep the system at resonance. The net effect now, at LF will = be an increased value of X shunting it. As your additional C reduces = and L increases, the residual at LF across the LF coil goes up. Now = adjust teh LF colil to bring it to resonance, then go back and redo the = MF L or C. Iterating between teh two until they both go. I'ts a complicated setup, with two frequencies and three variables to = play with - so an infinite set of values to end up with, but if I were = doing it, I'd make up a spreadsheet and play around with values until a = workable solution that resonated both antennas was found and looked OK. = Once resonated you can bring them to a match if needed. But on Rx just = resonating them ought to suffice Or use a circuit analysis prog. =20 Andy=20 www.g4jnt.com On 28 June 2018 at 20:04, Chris Wilson wrote: Hello Mal, Thanks Mal and Stefan, but Mal, I want to listen to and decode both = bands at the same time on 2 different receivers, sharing the one antenna. = I tried shorting out the loading coil but LF reception is much = poorer. Not sure how much of an effect no loading coil has at MF ,but = suspect a loading coil to resonate would be pretty helpful? Thursday, June 28, 2018, 7:55:55 PM, you wrote: > I use aircore loading and matching > Use 2 coils and SW between them for desired band > G3KEV --=20 Best regards, Chris mailto:dead.fets@gmail.com ------=_NextPart_000_001F_01D40FC8.E60BDD00 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
If you cannot hear or see the signals on the band of = interest=20 you cannot communicate, therefore it is important also to have  an=20 efficient RECEIVE system
An efficient Antenna system is very important for = both TX and=20 RX  especially with low level amateur radio signals .
I would adopt a different approach if I wanted to listen on two = separate=20 receivers simultaneously to two different amateur bands.
I would use two separate Antennas each one resonated on the band of = interest, in fact  I do this for MF/160  and MF/630
g3kev
 
Sent: Friday, June 29, 2018 6:53 AM
To: LineOne =
Subject: Re: LF: Can I match 2 frequencies with one loading=20 coil?
 
Mal ...
 
Did you not read the requirement properly?
 
It was for RECEIVE only.  So loss is of no consequence
AND
he wants to listen on two receivers simultaneously, so switching is = not an=20 option.
 
 
 
 
Andy=20
 
 
On 28 June 2018 at 22:16, Mal Hamilton <g3kevmal@talktalk.net> = wrote:
Andy
Your method too lossy and complicated, interaction etc
Use one coil for each band and switch  between them for the = desired=20
Band
G3KEV
 

On 28 Jun 2018, at 20:32, Andy Talbot <andy.g4jnt@gmail.com> wrote:

Try this, but you'll have to adjust iteratively:=20
Bands referred to as LF and MF
 
First make your LF loading coil so it resonates the antenna as it = stands.    Now make an MF loading coil.  The = problem is=20 that t=3Dwhen both are connected to the antenna teh lower value MF one = shunts=20 teh LF.  So add series C to the MF one to make a series tuned = circuit,=20 increasing the L to keep the system at resonance.   The net = effect=20 now, at LF will be an increased value of X shunting it.  As your=20 additional C reduces and L increases, the residual at LF across the LF = coil=20 goes up.    Now adjust teh LF colil to bring it to = resonance,=20 then go back and redo the MF L or C.  Iterating between teh two = until=20 they both go.
 
I'ts a complicated setup, with two frequencies and three = variables to=20 play with - so an infinite set of values to end up with, but if I were = doing=20 it, I'd make up a spreadsheet and play around with values until a = workable=20 solution that resonated both antennas was found and looked OK.  = Once=20 resonated you can bring them to a match if needed.   But on = Rx just=20 resonating them ought to suffice
 
Or use a circuit analysis prog.     =
 
Andy=20 =
 
 
On 28 June 2018 at 20:04, Chris Wilson <dead.fets@gmail.com> = wrote:


Hello=20 Mal,

Thanks Mal and Stefan, but Mal, I want to listen to and = decode=20 both bands
at the same time on 2 different receivers, sharing the = one=20 antenna. I
tried  shorting out the loading coil but LF = reception is=20 much poorer.
Not  sure how much of an effect no loading coil = has at=20 MF ,but suspect
a loading coil to resonate would be pretty=20 helpful?

Thursday, June 28, 2018, 7:55:55 PM, you = wrote:

>=20 I use aircore loading and matching
> Use 2 coils and SW = between them=20 for desired band
> G3KEV







--
Best=20 = regards,
Chris         &n= bsp;           &nb= sp;     =20 mailto:dead.fets@gmail.com


 
 
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