Return-Path: Received: from mtain-mj07.r1000.mx.aol.com (mtain-mj07.r1000.mail.aol.com [172.21.164.91]) by air-de07.mail.aol.com (v129.4) with ESMTP id MAILINDE074-5ebd4c578184e3; Mon, 02 Aug 2010 22:40:04 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mj07.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2F075380000BD; Mon, 2 Aug 2010 22:40:02 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Og7OY-0003pw-Ph for rs_out_1@blacksheep.org; Tue, 03 Aug 2010 03:38:22 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Og7OX-0003pn-Tx for rsgb_lf_group@blacksheep.org; Tue, 03 Aug 2010 03:38:21 +0100 Received: from blu0-omc1-s3.blu0.hotmail.com ([65.55.116.14]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Og7OW-00038r-Or for rsgb_lf_group@blacksheep.org; Tue, 03 Aug 2010 03:38:21 +0100 Received: from BLU146-W16 ([65.55.116.7]) by blu0-omc1-s3.blu0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Mon, 2 Aug 2010 19:38:11 -0700 Message-ID: X-Originating-IP: [67.60.204.92] From: Laurence KL7UK To: Date: Mon, 2 Aug 2010 18:38:12 -0800 Importance: Normal In-Reply-To: <359364.83864.qm@web86701.mail.ird.yahoo.com> References: ,<359364.83864.qm@web86701.mail.ird.yahoo.com> MIME-Version: 1.0 X-OriginalArrivalTime: 03 Aug 2010 02:38:11.0931 (UTC) FILETIME=[EA763AB0:01CB32B4] X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Content-Type: multipart/alternative; boundary="_45cbc498-070b-40c4-b84e-8aa4e12e4e9b_" Subject: RE: LF: Noise R75 - rs232 from smpsu - X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=FORGED_HOTMAIL_RCVD,HTML_20_30, 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: 3039400c89ae4c5781822a8d X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --_45cbc498-070b-40c4-b84e-8aa4e12e4e9b_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dave - can you enlighten me on the filter values both on the X and Y caps= and inductance AC side and filtering on the DC? I have about 5 bricks he= re; some I picked up in a market in Beijing (Beijing Lu akin to the old Ly= le st in london (dont think you spell it like that - that dates me)) - Ive= taken a couple apart and I have some that are 2 wire AC and some 3 wire= - all appear to have pretty good filtering and various screening material= s even the Chinese cheapies. Any values to knock off 137 especially welcom= e - of course each psu has a slightly different osc/pulse freq - some at= 60 some at 300Khz! The opto isolator really helped the AK rx with good/re= asonable signals from Japan every nite so far... =20 Im running out of good Oklahoman LF projects! =20 Laurence =20 Date: Fri, 23 Jul 2010 22:26:06 +0000 From: davepick@btinternet.com To: rsgb_lf_group@blacksheep.org Subject: Re: LF: Noise R75 - rs232 from smpsu - Laurence In my remote station I put the Dell brick in an Eddy box (die-cast box) wi= th a proper mains filter on the input and chokes and feed-through capacito= rs in the DC output lead. Drilled some holes for ventilation. Quiet as a= mouse. A linear PSU should also be fine but quite large. The RS232 is unbalanced of course, but if you run it in screened cable and= use a ferrite common-mode choke dies it not help? Dave G3YXM From: Laurence KL7UK To: lowfer@mailman.qth.net; rsgb_lf_group@blacksheep.org Sent: Friday, 23 July, 2010 21:47:56 Subject: LF: Noise R75 - rs232 from smpsu - =20 Anyone done any common mode noise mitigation from the RS232 port of the R7= 5 Rx> - the noise coming up from the SMPSU/processor from the old Dell put= er - cable is double screened - choking off using J (75) type has seen lit= tle improvement - this is my last hurdle to unimpeded remote rx on 137 -= any pointers appreciated - everythings bonded and Ive tried the on/off ea= rth tricks at various locations -=20 =20 Anyone had any success of powering a Dell D series from a non standard non= switched PSU? (the noise goes away when the DC from the Black Dell brick= is removed but it may also be partially screen/processor noise...) =20 with thanks =20 Laurence Kl7UK The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with= Hotmail. Get busy. =3D --_45cbc498-070b-40c4-b84e-8aa4e12e4e9b_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dave - can you enlighten me on the filter values both on the X= and Y caps and inductance AC side and filtering on the DC?  I have= about 5 bricks here; some I picked up in a market in Beijing (Beijin= g Lu akin to the old Lyle st in london (dont think you spell it= like that - that dates me)) - Ive taken a couple apart and I have some th= at are 2 wire AC and some 3 wire - all appear to have pretty good fil= tering and various screening materials even the Chinese cheapies. Any valu= es to knock off 137 especially welcome - of course each psu has a slightly= different osc/pulse freq - some at 60 some at 300Khz! The opto isola= tor really helped the AK rx with good/reasonable signals from Japan= every nite so far...
 
Im running out of good Oklahoman LF projects!
 
Laurence
 
Date: Fri, 23 Jul 2010 22:26:06 +0000
From: davepick@btinternet.com
= To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: Noise R75 - rs232 fro= m smpsu -

Laurence

In my remote station I put the Dell brick in an Eddy= box (die-cast box) with a proper mains filter on the input and chokes and= feed-through capacitors in the DC output lead. Drilled some holes for ven= tilation. Quiet as a mouse.
A linear PSU should also be fine but quite= large.
The RS232 is unbalanced of course, but if you run it in screene= d cable and use a ferrite common-mode choke dies it not help?

Dave= G3YXM

From: Laurence KL7UK <h= ellozerohellozero@hotmail.com>
= To: lowfer@mailman.qth.net; rsgb_lf_group@blacksheep.org
= Sent: Friday, 23 July, 2010= 21:47:56
Subject: LF:= Noise R75 - rs232 from smpsu -

 
Anyone done any common mode noise mitigation from the RS232 port= of the R75 Rx> - the noise coming up from the SMPSU/processor from the= old Dell puter - cable is double screened - choking off using J (75)= type has seen little improvement - this is my last hurdle to unimpeded re= mote rx on 137 - any pointers appreciated - everythings bonded and Ive tri= ed the on/off earth tricks at various locations -
 
Anyone had= any success of powering a Dell D series from a non standard non switched= PSU? (the noise goes away when the DC from the Black Dell brick is remove= d but it may also be partially screen/processor noise...)
 
wit= h thanks
 
Laurence Kl7UK

The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with= Hotmail. Get busy.
= =3D --_45cbc498-070b-40c4-b84e-8aa4e12e4e9b_--