Return-Path: Sender: (Marvin Kaye) To: lml@lancaironline.net Date: Sat, 05 Jun 2004 00:22:49 -0400 Message-ID: X-Original-Return-Path: Received: from [66.75.162.134] (HELO ms-smtp-02-eri0.socal.rr.com) by logan.com (CommuniGate Pro SMTP 4.2b4) with ESMTP id 130744 for lml@lancaironline.net; Fri, 04 Jun 2004 21:47:05 -0400 Received: from WALTERXP (cpe-24-161-205-142.bak.rr.com [24.161.205.142]) by ms-smtp-02-eri0.socal.rr.com (8.12.10/8.12.7) with SMTP id i551kVXs016825 for ; Fri, 4 Jun 2004 18:46:32 -0700 (PDT) X-Original-Message-ID: <009901c44a9e$ec756020$0100a8c0@WALTERXP> From: "Walter and Margo Dodson" X-Original-To: "Lancair Mailing List" Subject: HF Antenna Design X-Original-Date: Fri, 4 Jun 2004 18:46:30 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0096_01C44A64.3FC7CBE0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0096_01C44A64.3FC7CBE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable All you electronics guys out there, My work (ASB Avionics LLC, Mojave, CA) has an STC for an HF notch = antenna for the L-382G. It installs as a replacement ventral fin ahead = of the vertical stab. Its operating frequency is from 2k to 30k Hz. = The DC resistance of the notch is .004 Ohm. We are trying to figure the = current into the antenna in amperes. The output power from the coupler = is, I believe (and I must check this figure), 10k watts. I understand = there are variables in the shape of the antenna which may limit us = figuring this out without taking emperical mesurements. We need a = formula, even if it is fitted to empirical data, which will yeild an = input current over that range. I got wind of this today and wonder if anyone out there can help me? = I believe an integral from 2k to 30k of the appropriate formula will = yeild a solution. Trouble is, in my mind, writing that equation. Or, = for that matter, can an equation be written considering the shape of the = skin which acts as the emitter? The reactance of the emitter surface = may not be calculable and a fit to empirical data may be the only way to = write this equation. If any of you guys have antenna experience I would really appreciate a = bang on the pipes off the LML. I am wdodson@bak.rr.com. Thank you, Walter ------=_NextPart_000_0096_01C44A64.3FC7CBE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

All you electronics guys out = there,

My work (ASB Avionics LLC, = Mojave, CA) has=20 an STC for an HF notch antenna for the L-382G. It installs as = a=20 replacement ventral fin ahead of the vertical stab. Its = operating=20 frequency is from 2k to 30k Hz. The DC resistance of the = notch is=20 .004 Ohm. We are trying to figure the current into the = antenna in=20 amperes. The output power from the coupler is, I believe (and = I must=20 check this figure), 10k watts. I understand there are variables in = the=20 shape of the antenna which may limit us figuring this out without taking = emperical mesurements. We need a formula, even if it is fitted to=20 empirical data, which will yeild an input current over that=20 range.

I got wind of this = today and=20 wonder if anyone out there can help me? I believe an integral from = 2k to=20 30k of the appropriate formula will yeild a solution. Trouble is, = in my=20 mind, writing that equation. Or, for that matter, can an = equation be written considering the shape of the skin which = acts as=20 the emitter? The reactance of the emitter surface may not be = calculable=20 and a fit to empirical data may be the only way to write this=20 equation.

If any of you guys have antenna = experience I=20 would really appreciate a bang on the pipes off the LML. I am wdodson@bak.rr.com.

Thank you,

Walter

------=_NextPart_000_0096_01C44A64.3FC7CBE0--