Return-Path: Received: from mtain-ma05.r1000.mx.aol.com (mtain-ma05.r1000.mx.aol.com [172.29.96.13]) by air-me02.mail.aol.com (v126.13) with ESMTP id MAILINME022-8ba54b61959e2a0; Thu, 28 Jan 2010 08:48:14 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-ma05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1A17C38000160; Thu, 28 Jan 2010 08:48:12 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NaUhF-0002U7-OW for rs_out_1@blacksheep.org; Thu, 28 Jan 2010 13:46:09 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NaUhF-0002Ty-5c for rsgb_lf_group@blacksheep.org; Thu, 28 Jan 2010 13:46:09 +0000 Received: from fg-out-1718.google.com ([72.14.220.157]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NaUhD-0006hU-E2 for rsgb_lf_group@blacksheep.org; Thu, 28 Jan 2010 13:46:09 +0000 Received: by fg-out-1718.google.com with SMTP id 19so173012fgg.10 for ; Thu, 28 Jan 2010 05:46:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=SWOqE+Viy47hNcrijYyrpInyg/kJxvcH2VF0bjsECX4=; b=EqscU4e7I7wYDdtHqpcf4owxyNjzbvRCToXaRnn52DUAS8pHOf2QtouX6ilkYz0Qpk 7zedOkwjF6IkRqOSJa446WLa4Llyz/Llrh/x3HjE0PqefqsNWM7dz+cUOspaD8CvGnGh jYh2DE78MrYqmyF5LJ0pR36UrI6TTCw0qtqOE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=UlQdAeK5Th2oljwOvq+xZNZwpfY6ZmUuXRb3jmpPIurcpo4MsYLRFEQRjCIO2NNp2n Q1pcYbQUqi4QcdvL2VgYnGKkESv1/s9EljF7atUasVpO4xOe3fi8CM1UjrWj3Iv46hAX nsLnOQiN/QcL/RATJphx7YHdiudM9PZcq67TI= MIME-Version: 1.0 Received: by 10.239.165.72 with SMTP id w8mr1282057hbd.8.1264686365351; Thu, 28 Jan 2010 05:46:05 -0800 (PST) In-Reply-To: <4B614A11.6020509@telia.com> References: <1f0624b91001271133g22391461tfa8dc9a87c8f14d4@mail.gmail.com> <1f0624b91001271303v1eb7094bp659dba8418585e81@mail.gmail.com> <4B614A11.6020509@telia.com> Date: Thu, 28 Jan 2010 13:46:05 +0000 Message-ID: From: Andy Talbot To: rsgb_lf_group@blacksheep.org DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: RE: 500 kHz JT4A Content-Type: multipart/alternative; boundary=001485f90ec08f2140047e39bd10 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 x-aol-global-disposition: G x-aol-sid: 3039ac1d600d4b61959c7481 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --001485f90ec08f2140047e39bd10 Content-Type: text/plain; charset=ISO-8859-1 VERY TRUE.......... One solution for narrow band would them be to filter the output to remove the fundamental (and any other odd order) componets that cause the asymetry Andy www.g4jnt.com This email has been scanned for damaging side-effects by the health and safety police, is guaranteed to contain no substances hazardous to health, but may contribute to dissolving the nether and polar regions On 28 January 2010 08:25, Johan H. Bodin wrote: > Andy, > > such a doubler will work but the flip-flop is not a guarantee for a > perfect 50/50 square wave in this case. The flip-flop will be clocked by > both edges of *one* of the XOR input signals, which one depends on the > clock polarity (rising or falling edge) at the flip-flop input so the > flip-flop output will have the same duty cycle as one of the XOR input > signals. The traditional C.T. transformer will work equally well (or bad). > > 73 > Johan SM6LKM > > ---- > > Andy Talbot wrote: > > I was looking at driving push-pull transmitters from fundamental drive > > signals quite recently. > > > > How about a frequency doubler? The output doesn't have to have 1:1 > > mark-space ratio as it only clocks a flip-flop. And simple doubler can > > consists of a delay line (CR network with around 0.5us time constant) > > followed by a squarer to give a resulting waveform shifted in phase from > > the 500kHz drive signal. Then apply this one, along with the original > > to a two input XOR gate whose output will then consists of a 1MHz train > > suitable for dividing by 2 for a perfect 1:1 squarewave drive. > > > > > > Andy > > www.g4jnt.com > > --001485f90ec08f2140047e39bd10 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
VERY TRUE..........
=A0
One solution for narrow band would them=A0be to filter the output to= remove the fundamental (and any other odd order) componets that cause the= asymetry

Andy
www.g4jnt.= com

This email has been scanned for damaging side-effects by th= e health and safety police, is guaranteed to contain no substances hazardo= us to health, but may contribute to dissolving the nether and polar region= s


On 28 January 2010 08:25, Johan H. Bodin <jh.bodin@telia.com<= /a>> wrote:
Andy,

such a doubler= will work but the flip-flop is not a guarantee for a
perfect 50/50 squ= are wave in this case. The flip-flop will be clocked by
both edges of *one* of the XOR input signals, which one depends on the
= clock polarity (rising or falling edge) at the flip-flop input so the
f= lip-flop output will have the same duty cycle as one of the XOR input
signals. The traditional C.T. transformer will work equally well (or bad).=

73
Johan SM6LKM

----

Andy Talbot wrote:
> I was looking at driving= push-pull transmitters from fundamental drive
> signals quite recen= tly.
>
> How about a frequency doubler? =A0 =A0The output does= n't have to have 1:1
> mark-space ratio as it only clocks a flip-flop. =A0 And simple double= r can
> consists of a delay line (CR network with around 0.5us time= constant)
> followed by a squarer to give a resulting waveform shif= ted in phase from
> the 500kHz drive signal. =A0Then apply this one, =A0along with the or= iginal
> to a two input XOR gate whose output will then consists of= a 1MHz train
> suitable for dividing by 2 for a perfect 1:1 squarew= ave drive.
>
>
> Andy
> www.g4jnt.com <http://www.g4jnt.com>

=
--001485f90ec08f2140047e39bd10--