Return-Path: Received: (qmail 29309 invoked from network); 27 Apr 2000 11:56:51 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by redlabel.core.plus.net.uk with SMTP; 27 Apr 2000 11:56:51 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12kmos-0000Xn-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 27 Apr 2000 12:50:58 +0100 Content-Transfer-Encoding: 8bit Received: from bob.dera.gov.uk ([192.5.29.90]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12kmoo-0000Xi-00 for rsgb_lf_group@blacksheep.org; Thu, 27 Apr 2000 12:50:54 +0100 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id MAA16048; Thu, 27 Apr 2000 12:53:43 +0100 (BST) X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 16138 invoked from network); 27 Apr 2000 12:47:17 -0000 Received: from gauntlet.mail.dera.gov.uk (172.16.9.10) by baton.dera.gov.uk with SMTP; 27 Apr 2000 12:47:17 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: by gauntlet.mail.dera.gov.uk; id LAA09728; Thu, 27 Apr 2000 11:36:45 GMT Received: from unknown(146.80.11.40) by gauntlet.mail.dera.gov.uk via smap (3.2) id xma009687; Thu, 27 Apr 00 11:36:31 GMT Received: from frn-gold-1.dera.gov.uk (unverified) by mailguard.dera.gov.uk (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Thu, 27 Apr 2000 12:54:35 +0100 Received: by FRN-GOLD-1 with Internet Mail Service (5.0.1460.8) id <2J0999HP>; Thu, 27 Apr 2000 12:48:55 +0100 Message-ID: <3617AC3245C2D1118A840000F805359C0175289F@pdw-mercury-1.dera.gov.uk> From: "Talbot Andrew" To: rsgb_lf_group@blacksheep.org Subject: LF: RE: High stability drive sources Date: Thu, 27 Apr 2000 12:48:52 +0100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.0.1460.8) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: > Are more of these becoming available ? A lot have been bought up by > microwave operators recently. > > The best way to use these it take out the oscillator module which runs > off 12 Volts and use that individually, then throw the rest away. A > bit wastefull perhaps, but the rest of the electronics is specific to > providing a source for a single UHF frequency and not very adaptable. > > > The Toyo oscillator itself is very good but does not have voltage > control of fine trimming. I published a modification to allow this in > a Microwave newsletter some years ago when these units first appeared. > Don't know the Racal unit, but believe it does already have varicap > fine tuning. > > Andy G4JNT > > > > ---------- > From: Alan Melia[SMTP:Alan.Melia@btinternet.com] > Reply To: rsgb_lf_group@blacksheep.org > Sent: 2000-04-26 21:08 > To: rsgb_lf_group > Subject: LF: High frequency-stability drive sources > > Hi there has been some discussion about stable drive sources for > narrow band > modes. One possible source that sometimes becomes available these days > is a > Pye/Philips unit which used to be used as the frequency source for > quasi-synchronous radio communication systems, like the wide area > coverage > systems of the emergency and utility services. The unit model number > is > HS400 and it contains circuitry to lock a crystal to a 5MHz ovened > standard > oscillator (2 types with either a Toyo or a Racal unit). The stability > available is a few parts in 10^9. I think these units are now obsolete > so > may become more easily available. They are a little large being 19in > rack-mount units. If anyone does find one I have the technical > details. > > 73 de Alan G3NYK > Alan.Melia@btinternet.com > > > > > -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.