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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: Dear Warren, LF Group, It is possible to add taps to the output transformer for different output powers, although adding the extra bits of wire will tend to increase leakage inductance and make the construction more complicated. Personally I have found varying the DC supply voltage is mare convenient, as G4WGT has done. If you do have a tapped output winding, I would suggest limiting yourself to one or two taps only - how many levels of output power do you really need anyway? If you just require a low power setting for tuning-up purposes, and are stuck with a fixed-voltage PSU, an alternative is a large resistor inserted in series with the DC supply. Although it is inefficient, it does provide inherent current limiting, making it hard to blow up the PA while tuning. [...] Content analysis details: (0.2 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [212.82.108.235 listed in list.dnswl.org] 0.2 STOX_REPLY_TYPE STOX_REPLY_TYPE 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines X-Scan-Signature: 1f795a2ee1ecd56682b47ad11969b3d3 Subject: LF: Re: M0BMU mods to the G0MRF PA Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original 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=0.1 required=5.0 tests=MISSING_OUTLOOK_NAME 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 x-aol-global-disposition: G X-AOL-SCOLL-AUTHENTICATION: mtain-dc02.r1000.mx.aol.com ; domain : btopenworld.com DKIM : fail x-aol-sid: 3039ac1d408250cdd5106d94 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Dear Warren, LF Group, It is possible to add taps to the output transformer for different output powers, although adding the extra bits of wire will tend to increase leakage inductance and make the construction more complicated. Personally I have found varying the DC supply voltage is mare convenient, as G4WGT has done. If you do have a tapped output winding, I would suggest limiting yourself to one or two taps only - how many levels of output power do you really need anyway? If you just require a low power setting for tuning-up purposes, and are stuck with a fixed-voltage PSU, an alternative is a large resistor inserted in series with the DC supply. Although it is inefficient, it does provide inherent current limiting, making it hard to blow up the PA while tuning. Cheers, Jim Moritz 73 de M0BMU