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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: Well, i find it not strange at all that it works. The discussed antennas are just impedance converters. The input impedance is in the range of 1 MOhm and the output impdeance is lower. Did you never see a (small) voltage on an oscilloscope when a simple probe is connected, while transmitting on LF/MF? The scope has an input impedance of 1 MOhm (and some pF). Now take an oscilloscope with battery supply, connect the probe and put it into a Helium balloon and let the probe hang down. Then let the stuff rise to near your TX antenna and see the signal on the scope. It would also work without a ground! (Then see all the stuff crashing down in your neighbours swimming pool). [...] Content analysis details: (-2.6 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [129.206.210.211 listed in list.dnswl.org] -0.3 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Scan-Signature: 0b2d339ae1d48966556dfb6ad64e2bce Subject: Re: R: Re: Fwd: Re: LF: VK1OD's analysis of the MiniWhip antenna Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit 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 Status: O X-Status: X-Keywords: X-UID: 3458 Well, i find it not strange at all that it works. The discussed antennas are just impedance converters. The input impedance is in the range of 1 MOhm and the output impdeance is lower. Did you never see a (small) voltage on an oscilloscope when a simple probe is connected, while transmitting on LF/MF? The scope has an input impedance of 1 MOhm (and some pF). Now take an oscilloscope with battery supply, connect the probe and put it into a Helium balloon and let the probe hang down. Then let the stuff rise to near your TX antenna and see the signal on the scope. It would also work without a ground! (Then see all the stuff crashing down in your neighbours swimming pool). Compared to the scope, the discussed antennas just have to be more sensitive, minimizing all that noise stuff, while my scope starts at 5mV/div. And 1 mV signal level would be a BIG signal for the RX! :-) 73, Stefan/DK7FC