Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mc03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2FEA438000086; Sat, 30 Jun 2012 05:24:15 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SkttR-0005R6-4H for rs_out_1@blacksheep.org; Sat, 30 Jun 2012 10:23:05 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SkttQ-0005Qx-Lc for rsgb_lf_group@blacksheep.org; Sat, 30 Jun 2012 10:23:04 +0100 Received: from smtpa1.mediabeam.com ([194.25.41.13] helo=smtpa2.mediabeam.com) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1SkttO-0004ug-Pw for rsgb_lf_group@blacksheep.org; Sat, 30 Jun 2012 10:23:03 +0100 Received: from IMAP1 (balancer7.mediabeam.com [10.100.1.80]) by smtpa2.mediabeam.com (8.13.8/8.13.1) with ESMTP id q5U9MxAZ010298 for ; Sat, 30 Jun 2012 11:22:59 +0200 Received: from [192.168.178.33] (37-4-36-228-dynip.superkabel.de [37.4.36.228] (may be forged)) (authenticated bits=0) by smtpa.mediabeam.com (8.13.8/8.13.1) with ESMTP id q5U9MvhI010279 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sat, 30 Jun 2012 11:22:59 +0200 Message-ID: <4FEEC581.7020804@kabelmail.de> Date: Sat, 30 Jun 2012 11:23:13 +0200 From: DK1IS User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <00a901cd563a$b02b6be0$0200a8c0@boxa> <4FEE2407.3050603@iup.uni-heidelberg.de> In-Reply-To: <4FEE2407.3050603@iup.uni-heidelberg.de> 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: Am 29.06.2012 23:54, schrieb Stefan Schäfer: > MF, > > It becomes better! > > I just realised that this filter is perfect to protect a receiver like > the IC706 when using a BIG antenna as the MF receive antenna. It will > be easy to build a passive circuit out of a transformer 50 Ohm -> 18 > kOhm -->Filter--> 18 kOhm -> 50 Ohm. This can be put in a small box > and then there will be no problems! I remember how the 706 and others > behave on long wires, i.e. multi-band antennas... > > 73, Stefan > Hi Stefan, [...] 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 [194.25.41.13 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: f1498eebf16822c5ea85527a90413169 Subject: Re: LF: RE: Fwd: Help needed, mechanical filters Content-Type: multipart/alternative; boundary="------------090003070508050409060405" 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-SCOLL-SCORE: 0:2:329035136:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d604b4feec5be5b62 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. --------------090003070508050409060405 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by smtpa.mediabeam.com id q5U9MvhI010279 Am 29.06.2012 23:54, schrieb Stefan Sch=E4fer: > MF, > > It becomes better! > > I just realised that this filter is perfect to protect a receiver like=20 > the IC706 when using a BIG antenna as the MF receive antenna. It will=20 > be easy to build a passive circuit out of a transformer 50 Ohm -> 18=20 > kOhm -->Filter--> 18 kOhm -> 50 Ohm. This can be put in a small box=20 > and then there will be no problems! I remember how the 706 and others=20 > behave on long wires, i.e. multi-band antennas... > > 73, Stefan > Hi Stefan, using those filters in the antenna circuit of a rx keep in mind that the=20 maximum input voltage is rather limited due to the high internal Q of=20 the mechanical resonators. Here I have some 200-kHz-units from RFT with=20 maximum input voltage of 2V resp. -10 dB relative to what ever. So be=20 careful when using them with a seperat rx antenna! 73, Tom, DK1IS --------------090003070508050409060405 Content-Type: text/html; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by smtpa.mediabeam.com id q5U9MvhI010279 Am 29.06.2012 23:54, schrieb Stefan Sch=E4fer:
MF,

It becomes better!

I just realised that this filter is perfect to protect a receiver like the IC706 when using a BIG antenna as the MF receive antenna. It will be easy to build a passive circuit out of a transformer 50 Ohm -> 18 kOhm -->Filter--> 18 kOhm -> 50 Ohm. This can be put in a small box and then there will be no problems! I remember how the 706 and others behave on long wires, i.e. multi-band antennas...

73, Stefan

Hi Stefan,

using those filters in the antenna circuit of a rx keep in mind that the maximum input voltage is rather limited due to the high internal Q of the mechanical resonators. Here I have some 200-kHz-units from RFT with maximum input voltage of 2V resp. -10 dB relative to what ever. So be careful when using them with a seperat rx antenna!

73,
Tom, DK1IS
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