Envelope-to: dave@picks.force9.co.uk Delivery-date: Tue, 05 Jul 2005 20:39:00 +0100 Received: by ptb-mxcore04.plus.net with spam-scanned (PlusNet MXCore v2.00) id 1DptG0-00037G-6F for dave@picks.force9.co.uk; Tue, 05 Jul 2005 20:39:00 +0100 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore04.plus.net with esmtp (PlusNet MXCore v2.00) id 1DptG0-00036U-1S for dave@picks.force9.co.uk; Tue, 05 Jul 2005 20:39:00 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1DptFl-0004Dr-Eb for rs_out_1@blacksheep.org; Tue, 05 Jul 2005 20:38:45 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1DptFk-0004Di-OB for rsgb_lf_group@blacksheep.org; Tue, 05 Jul 2005 20:38:44 +0100 Received: from mk-smarthost-8.mail.uk.tiscali.com ([212.74.114.47]) by relay1.thorcom.net with esmtp (Exim 4.51) id 1DptIg-0004oE-Q4 for rsgb_lf_group@blacksheep.org; Tue, 05 Jul 2005 20:41:48 +0100 Received: from dsl-80-43-47-148.access.as9105.com ([80.43.47.148]:2117 helo=tcs01) by mk-smarthost-8.mail.uk.tiscali.com with smtp (Exim 4.30) id 1DptFd-00090A-Dg for rsgb_lf_group@blacksheep.org; Tue, 05 Jul 2005 19:38:37 +0000 From: "Gary - G4WGT" To: rsgb_lf_group@blacksheep.org Date: Tue, 5 Jul 2005 20:37:49 +0100 Message-ID: MIME-Version: 1.0 X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: <000001c580ea$8c2a1d40$6507a8c0@Main> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 Subject: LF: RE: Re: RE: G0MRF 300w Tx PA mods Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit 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 X-PN-SpamFiltered: by PlusNet MXCore (v2.00) Hi Alan & LF, You (Alan G3NYK) wrote :- "It might be worth sticking a big 50 volt zener across the power unit to clip any transients." That sounds worth a try. And "What sort of PSU is it ??" It is a simple affair using a big toriod transformer, 40V x 40V at 6.3A 500VA with windings in parallel smoothed by 2 x 10,000MFD 100V capacitors (voltage is about 45V before going to transmit state) & a smaller toroid to supply about 28V DC to 24V & 12V 3 leg IC regulators within the transmitter. I am only using the variac at present because I wanted to bring it up gently until I was sure that all is well, I will need to fit some sort of soft start when I am happy with it & know I can run it at max volts, I can then remove the variac. Thanks for your feedback. Regards, Gary - G4WGT - IO83qp Web : http://myweb.tiscali.co.uk/wgtaylor