Return-Path: Received: (qmail 15899 invoked from network); 21 Feb 2001 15:40:29 -0000 Received: from unknown (HELO murphys-inbound.servers.plus.net) (212.159.14.225) by 10.226.25.101 with SMTP; 21 Feb 2001 15:40:29 -0000 Received: (qmail 29240 invoked from network); 21 Feb 2001 15:40:33 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 21 Feb 2001 15:40:33 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14VbGh-0005jg-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 21 Feb 2001 15:33:27 +0000 Received: from mail2.globocabo.com.br ([200.231.181.97] helo=ntweb.globocabo.com.br) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14VbGc-0005jb-00 for rsgb_lf_group@blacksheep.org; Wed, 21 Feb 2001 15:33:23 +0000 Received: from spovdesi1625 (SPOVD-ESI-1625 [5.8.14.13]) by ntweb.globocabo.com.br with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2653.13) id FKWLNQAK; Wed, 21 Feb 2001 12:31:16 -0300 Message-ID: <00e801c09c1b$36aaff00$0d0e0805@globocabo.com.br> From: "PY3CRX PY2PLL" To: "LF Group" Subject: LF: TECH: LF Converters Date: Wed, 21 Feb 2001 12:30:17 -0300 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Hi ... I've been using a MC1496 as a mixer and decided to try those SBLs from Minicircuits. But the models that cover down to few KHz are quite expensive and not available here. Re-reading the Minicircuits book I have (from 1993, 700 pages or so) they say that for some applications we can use the SIG port as output and the the IF port as input when we need to "receive from DC to several MHz". This is the case below 500KHz for cheap SBL1, SRA1, etc or even to an high intercept home made DDBM. The isolation remains more or less the same, so the SWR. I checked this inverting feature on SBL1, SRA1 and TFM2. All units gave the same insertion loss (6.5dB) and produced the same LO attenuation at receiver input (-45dBc). I use a MAV11 as post amp. The performance actually is better than the MC1496 bug (less noise) and 82Hz ZEVS signal still there, so the regular utilities on 16K, 18k2, 18k3, 19k8, 21k4, 24k0 ... and some new ones between 50K and 100K yesterday (rtty/msk). 73 Marcus PY3CRX/PY2PLL S. B. do Campo - GG66rf http://py.qsl.br Active from "DC" to 24GHz