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The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: Hello Group, Planning a new single-ended Class E PA for my activities on the Dreamers Band (8.27 kHz) two questions came up - perhaps someone can help me: -  Being interested only in on-off-keying I´m concerned about the capacitor in parallel to the power FET which in my case on VLF will be in the uF range. If the DC supply is on and without gate drive this capacitor is charged to the DC supply voltage. At the first positive gate pulse it discharges via the drain-source-path, the current being limited only by parasitc impedances - a poorly defined condition which usually has to be avoided. Does this mean that I have to apply drive continously and key the DC power supply only, perhaps synchronously to the next positive drive pulse? [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 8a92398c4d799328418d0bdb7e7fa4f8 Subject: LF: Class E PA Content-Type: multipart/alternative; boundary="------------7559FF72431D71E07F12D648" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=HTML_MESSAGE 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 This is a multi-part message in MIME format. --------------7559FF72431D71E07F12D648 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by smtp.kabelmail.de id w97HmNUA012584 Hello Group, Planning a new single-ended Class E PA for my activities on the Dreamers=20 Band (8.27 kHz) two questions came up - perhaps someone can help me: -=C2=A0 Being interested only in on-off-keying I=C2=B4m concerned about t= he=20 capacitor in parallel to the power FET which in my case on VLF will be=20 in the uF range. If the DC supply is on and without gate drive this=20 capacitor is charged to the DC supply voltage. At the first positive=20 gate pulse it discharges via the drain-source-path, the current being=20 limited only by parasitc impedances - a poorly defined condition which=20 usually has to be avoided. Does this mean that I have to apply drive=20 continously and key the DC power supply only, perhaps synchronously to=20 the next positive drive pulse? - Is there any rule of thumb for the inductance of the rf choke in the=20 drain-power supply path? Thanks for any idea! 73, Tom, DK1IS www.qrz.com/db/dk1is --------------7559FF72431D71E07F12D648 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by smtp.kabelmail.de id w97HmNUA012584

Hello Group,

Planning a new single-ended Class E PA for my activities on the Dreamers Band (8.27 kHz) two questions came up - perhaps someone can help me:

-=C2=A0 Being interested only in on-off-keying I=C2=B4m concerned about the capac= itor in parallel to the power FET which in my case on VLF will be in the uF range. If the DC supply is on and without gate drive this capacitor is charged to the DC supply voltage. At the first positive gate pulse it discharges via the drain-source-path, the current being =C2=A0lim= ited only by parasitc impedances - a poorly defined condition which usually has to be avoided. Does this mean that I have to apply drive continously and key the DC power supply only, perhaps synchronously to the next positive drive pulse?
=C2=A0
-=C2=A0 Is there any rule of thumb for the inductance of the rf choke in the drain-power supply path?

Thanks for any idea!

73,
Tom, DK1IS
www.qrz.com/db/dk1is

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