Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-di03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1C736380000D1; Tue, 6 Nov 2012 18:29:55 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1TVsZv-00046R-Ab for rs_out_1@blacksheep.org; Tue, 06 Nov 2012 23:29:07 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1TVsZu-00046I-Nt for rsgb_lf_group@blacksheep.org; Tue, 06 Nov 2012 23:29:06 +0000 Received: from smtpout3.wanadoo.co.uk ([80.12.242.59] helo=smtpout.wanadoo.co.uk) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1TVsZr-0004ec-Sl for rsgb_lf_group@blacksheep.org; Tue, 06 Nov 2012 23:29:05 +0000 Received: from AGB ([2.26.46.164]) by mwinf5d43 with ME id LPV21k0043YYEey03PV2z5; Wed, 07 Nov 2012 00:29:02 +0100 Message-ID: From: "Graham" To: References: <002901cdbc3e$193684d0$0501a8c0@xphd97xgq27nyf> <1352239007.87220.YahooMailNeo@web133201.mail.ir2.yahoo.com> In-Reply-To: <1352239007.87220.YahooMailNeo@web133201.mail.ir2.yahoo.com> Date: Tue, 6 Nov 2012 23:28:59 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. 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: LOL Well I work on a 1:400 efficiency for my Mf Ae , so to radiate 1 watt erp , that's 400 watts carrier power to the Ae, I can do the same on 7 meg with 500 mW to the same Ae .... dont forget 'we' had to change the reported wspr power level to 'erp' as the Ae feed powers where so big , until then it was Ae feed power , which made very little sense , but this was a long time ago, before everyone had (except me ) has class e/d amps [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [80.12.242.59 listed in list.dnswl.org] 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: da503d40de1d15ba476c143c8a26a457 Subject: Re: LF: TRANSVERTERS Content-Type: multipart/alternative; boundary="----=_NextPart_000_014B_01CDBC76.7F5A7590" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_40_50,HTML_MESSAGE, 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-sid: 3039ac1da60750999d731826 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ------=_NextPart_000_014B_01CDBC76.7F5A7590 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable LOL Well I work on a 1:400 efficiency for my Mf Ae , so to = radiate 1 watt erp , that's 400 watts carrier power to the = Ae, I can do the same on 7 meg with 500 mW to the same Ae .... = dont forget 'we' had to change the reported wspr power level = to 'erp' as the Ae feed powers where so big , until then it = was Ae feed power , which made very little sense , but this was = a long time ago, before everyone had (except me ) has class e/d = amps=20 It all stems from the race to dB's , as you can see now Gus = has a decode at -20 dB across the pond , where Stefan, just a = new boy to 500 has only -23 dB , but I know Gus was building = a new washing machine size PA over the summer , looks like its = running on Half load ;--)=20 73 -G.. I From: M0FMT=20 Sent: Tuesday, November 06, 2012 9:56 PM To: rsgb_lf_group@blacksheep.org=20 Subject: Re: LF: TRANSVERTERS Hi Graham Thought that WSPR stuff was supposed to be ultra low power? How come its blowing rigs up? Could it be that the Wisper is really a = blooming great shout and we have a misnomer which is an advertising = euphemism. Just pile on the power and be heard at all costs? Well it's = an ill wind...... ! 73 es GL Pete M0FMT IO91UX From: Graham To: rsgb_lf_group@blacksheep.org=20 Sent: Tuesday, 6 November 2012, 18:57 Subject: Re: LF: TRANSVERTERS But what are you sending with the reduced power rig ? SSB ... Normal CW Opera all have low duty cycles and = result in low heat build up But if you running at 100% key down sending qrss and the = like , then , yes the rig will heat up , in the early days I = always though wspr should of been named Icarus , with the = number of thermal run a ways caused by 100% duty over 120 seconds = ( not a problem at Hf where power levels are low, but down here = at 1:400 efficiency's =3D a lot of heat) The rig will have a class AB1 or similar PA with high = standing bias to reduce cross over distortion =3D splatter on ssb = , so standing dissipation will be high ..not much you can do ... = add a fan to cool the heat sink , but be careful of the thermal = gradients , out side cold , wont mean inside is also at the right = temp ..may still be very hot , if parasitic 'ambient' cooling = is part of the equation and the fan is only cooling the last = part of the heat path .. 73 -G.. From: mal hamilton=20 Sent: Tuesday, November 06, 2012 4:45 PM To: rsgb=20 Subject: LF: TRANSVERTERS RIG/TRANSVERTER HEAT I have noticed when running a Transceiver at low power for Transverter = or other use the Transceiver PA gets very HOT so it would appear that = this is an inefficient approach except the Transceiver has a dedicated = low power output. I was wondering what system was used to reduce this power. It would be = better to disable the PA and take the output from the driver stage. It is vy noticeable on an IC-706 de G3KEV ------=_NextPart_000_014B_01CDBC76.7F5A7590 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
LOL  Well  I work  on  a   = 1:400 =20 efficiency  for  my   Mf Ae  ,  so  = to =20 radiate   1 watt  erp  , that's   400 = watts =20 carrier  power to  the  Ae,  I can do the  = same  on 7 meg  with  500 mW to the  same  = Ae ....=20 dont  forget  'we' had to  change the  =20 reported   wspr  power  level  to  = 'erp' =20 as  the Ae feed powers   where  so  big  , = until  then   it was Ae  feed  power , = which =20 made  very little  sense  , but this   = was  a=20 long  time  ago, before  everyone  had  (except = me=20 )  has  class  e/d  amps
 
It all  stems  from the  race  to  = dB's  , as=20 you  can see  now  Gus  has  a decode  = at =20 -20 dB  across  the  pond , where  Stefan, just = a =20 new  boy to 500   has only  -23  dB  , = but  I=20 know  Gus  was  building  a new  washing =20 machine  size  PA  over the  summer , looks  = like=20 its  running  on  Half load  ;--)
 
73 -G..
 
 
 
I

From: M0FMT
Sent: Tuesday, November 06, 2012 9:56 PM
To: rsgb_lf_group@blacksheep.org= =20
Subject: Re: LF: TRANSVERTERS

Hi Graham
 
Thought that WSPR stuff was supposed to be = ultra low=20 power?
How come its blowing rigs up? Could it be = that the=20 Wisper is really a blooming great shout and we have a misnomer = which is an=20 advertising euphemism. Just pile on the power = and be heard=20 at all costs? Well it's an ill wind...... = !

73 es GL Pete M0FMT = IO91UX
From: Graham <g8fzk@g8fzk.fsnet.co.uk>To: = rsgb_lf_group@blacksheep.org=20
Sent: Tuesday, 6 = November=20 2012, 18:57
Subject: Re: LF:=20 TRANSVERTERS

But what  are  you  sending  with the  = reduced=20 power   rig  ?
 
SSB  ...  Normal  CW    = Opera  =20 all  have   low   duty cycles   = and =20 result  in low  heat  build  up
 
But if  you  running  at   100% = key  =20 down  sending   qrss  and  the  = like =20  , then  , yes the  rig  will  heat  up = , in=20 the  early  days  I always though   = wspr  should=20 of  been   named  Icarus    , with=20 the  number  of thermal  run a ways  caused =20 by   100% duty over  120 seconds   ( = not =20 a  problem at Hf where  power  levels  are  = low,=20 but  down here  at   1:400  = efficiency's  =3D=20 a  lot of heat)
 
The  rig  will  have a  class  AB1  = or  similar   PA  with  high  = standing =20 bias to  reduce  cross over  distortion  =3D = splatter =20 on ssb  , so  standing  dissipation  will  = be =20 high ..not much  you  can  do ...  add  = a  fan=20 to   cool the  heat sink , but  be  careful = of=20 the  thermal  gradients  , out  side  cold , = wont=20 mean inside  is also  at the  right  temp =20 ..may  still  be very  hot , if  parasitic =20 'ambient'  cooling  is  part of the  equation =  and=20 the  fan is only  cooling  the  last  part of = the  heat  path ..
 
 73 -G..
 
 

From: mal hamilton
Sent: Tuesday, November 06, 2012 4:45 PM
To: rsgb
Subject: LF: TRANSVERTERS

   RIG/TRANSVERTER = HEAT
I have noticed when running a Transceiver at = low power=20 for Transverter or other use the Transceiver PA gets very HOT so it = would=20 appear that this is an inefficient approach except the Transceiver has = a=20 dedicated low power output.
I was wondering what system was used to reduce = this=20 power. It would be better to disable the PA and take the output from = the=20 driver stage.
It is vy noticeable on an IC-706
 
de G3KEV
 


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