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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: Hello Dimitris! A lot of interesting info about ferrite rod ants and results, but on Russian language: http://136.su/index.php/topic,119.0.html 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 [37.140.190.203 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rw3adb[at]yandex.ru) 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: ac0f6ff1af52b6036ac1f4fe0c2bd52c Subject: Re: LF: Re: a lot of ferrite Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8 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=none 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 Hello Dimitris! A lot of interesting info about ferrite rod ants and results, but on Russian language: http://136.su/index.php/topic,119.0.html Use translator babelfish or other and use links and schematics. At once - UA3AGC from Minussinsk, East Siberia NO66, nr Krasnoyarsk was received in DM4TR location JO61de - QRB ~5000 km! - and VO1NA also too! UA3AGC DE DM4TR http://136.su/index.php/topic,18.msg7095.html#msg7095 http://136.su/index.php/topic,119.msg7099.html#msg7099 VO1NA DE DM4TR http://136.su/index.php/topic,119.msg13881.html#msg13881 The ferrite rod ant was used on DM4TR grabber in great QRM from local MW broadcast situated in near QTH - ~ 900m! The great RX reports was in that situation! The other great forum topic and results will be interesting for you on the other russian forum: http://www.radioscanner.ru/forum/topic22993.html 73! Roman, RW3ADB > Minor correction, the calculated relative permeability should be about > 500, I made a mistake in the initial calculation. I just discover why > they call it initial permeability (bad joke) :-) > > 73, Dimitris VK2COW > > Στις Σάβ, 12 Ιαν 2019 στις 2:48 μ.μ., ο/η Dimitrios Tsifakis > έγραψε: > >> Hi LF group, >> >> I have managed to acquire a few very large ferrite rods (36 cm x 10 cm >> x 2 cm). The material is unknown but I managed to form a square >> 'toroid' with four of them (they are heavy so gravity was enough to >> keep everything in place for a measurement) and I measured about 15 uH >> for 4 turns at 0.1 MHz, which if I have done the calculations >> correctly implies a relative permeability of about 1000. >> >> The R of the impedance of the square loop was low (<0.2 ohm) at 0.1 >> MHz and it increased fast with frequency (170 ohm at 5 MHz!). >> >> The question is, what LF/VLF experiment would you do if you had half a >> dozen of these rods? >> >> 73, Dimitris VK2COW -- 73! Roman, RW3ADB