I need it! Gary Jim Wilhite <[EMAIL PROTECTED]> wrote: Hello All:
Does anyone need a manual copy of a Heath SB 620? I have a copy of most of it. The manual covers the 455 KC IF frequency complete with diagrams and build information. This is a good clear copy for cost of 5 bucks mailed in the US. First person to email me gets it. 73 Jim W5JO ______________________________________________________________ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com From [EMAIL PROTECTED] Mon Nov 22 23:17:59 2004 Return-Path: <[EMAIL PROTECTED]> Delivered-To: [email protected] Received: from email-out-01.biz.rr.com (email-out-01.biz.rr.com [24.30.203.209]) by mailman.qth.net (Postfix) with ESMTP id 19BC1859C00 for <[email protected]>; Mon, 22 Nov 2004 23:17:58 -0500 (EST) Received: from fep03.biz.rr.com (fep03.biz.rr.com [24.30.203.200]) by email-out-01.biz.rr.com (8.12.10/8.12.10) with ESMTP id iAN4Bn9N020093; Mon, 22 Nov 2004 23:11:49 -0500 (EST) Received: from home1 ([66.142.141.22]) by fep03.biz.rr.com with ESMTP id <[EMAIL PROTECTED]>; Mon, 22 Nov 2004 23:11:48 -0500 From: "John Coleman, ARS WA5BXO" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]>, "'Discussion of AM Radio'" <[email protected]> Subject: RE: [AMRadio] AM Usage with Linear AMPS Date: Mon, 22 Nov 2004 22:11:49 -0600 Message-ID: <[EMAIL PROTECTED]> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.3416 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 In-reply-to: <[EMAIL PROTECTED]> Importance: Normal Cc: X-BeenThere: [email protected] X-Mailman-Version: 2.1.4 Precedence: list Reply-To: Discussion of AM Radio <[email protected]> List-Id: Discussion of AM Radio <amradio.mailman.qth.net> List-Unsubscribe: <http://mailman.qth.net/mailman/listinfo/amradio>, <mailto:[EMAIL PROTECTED]> List-Archive: <http://mailman.qth.net/mailman/private/amradio> List-Post: <mailto:[email protected]> List-Help: <mailto:[EMAIL PROTECTED]> List-Subscribe: <http://mailman.qth.net/mailman/listinfo/amradio>, <mailto:[EMAIL PROTECTED]> X-List-Received-Date: Tue, 23 Nov 2004 04:17:59 -0000 My experience (which is very little when it come to these sweep tube rigs) is they or rated for a belch or some thing short and don't hold up to a fix channel field day adventure with out tube replacement. I had a DuaoBander mobile for a while rated a 400 watts PEP input I never saw more than 150 watts output while whistling in the mike. It was in perfect condition and would light a 50 watt bulb with normal speech. I thought it would have blown it out. I was very disappointed. Yet, it was one of the most heard radios all over the country by many AMers in the late 80s. John, WA5BXO -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Brian Carling Sent: Monday, November 22, 2004 9:55 PM To: Discussion of AM Radio Subject: RE: [AMRadio] AM Usage with Linear AMPS Aren't there a lot of commercially built amateur radio linear amplifiers and RF finals that exceeded he manufacturers MAX Pdiss rathings over the years, by adding a COOLING FAN to take away the extra heat? One thinks of MANY sweep tubes rated for so-called Pdiss of 16 watts and 20 watts that are regularly run at hundreds of watts of RF! The tubes don't seem to melt. I think of the ubiquitous 6JS6C with a rating of 30 watts. Yaesu ran a pair of these at 260 watts input in their FT101 series. Many guys ran them at 260 watts p.e.p. on SSB and 260 watts CW. Assuming 65% efficiency, you have 35% of 260 watts going into the plates. That is to say 91 watts split between the two tubes. UH oh - POP! But no, they didn't. Then when you throttle that FT-101 back to 40 watts input on AM and go to your 30% efficiency (if it is) then you are actually putting only 20 watts carrier per tube which is SAFER. Is that correct? How about some of the othre rigs that rated their 2 sweep tube finals for 560 Watts or even 800 watts!? Then youhave peak Pdisses of 140 to 200 watts between the two sweep tubes, most of which are rated for no more than 40 watts.
