Return-Path: X-Spam-DCC: paranoid 1181; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE,RATWARE_GECKO_BUILD autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id t8UDcFXx013262 for ; Wed, 30 Sep 2015 15:38:15 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ZhHWy-0004Gp-M2 for rs_out_1@blacksheep.org; Wed, 30 Sep 2015 14:34:48 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ZhHWy-0004Gg-6M for rsgb_lf_group@blacksheep.org; Wed, 30 Sep 2015 14:34:48 +0100 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.86) (envelope-from ) id 1ZhHVt-0000AY-Tq for rsgb_lf_group@blacksheep.org; Wed, 30 Sep 2015 14:34:47 +0100 Received: from dovecot03.posteo.de (dovecot03.posteo.de [172.16.0.13]) by mout01.posteo.de (Postfix) with ESMTPS id A35932095F for ; Wed, 30 Sep 2015 15:33:28 +0200 (CEST) Received: from mail.posteo.de (localhost [127.0.0.1]) by dovecot03.posteo.de (Postfix) with ESMTPSA id 3nQz7D2hgGz5vN7 for ; Wed, 30 Sep 2015 15:33:28 +0200 (CEST) Message-ID: <560BE4A7.1010905@posteo.de> Date: Wed, 30 Sep 2015 15:33:27 +0200 From: DK7FC User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <579355A36AEE9D4FA555C45D556003AB1B2153E8@servigilant.vigilant.local> In-Reply-To: <579355A36AEE9D4FA555C45D556003AB1B2153E8@servigilant.vigilant.local> X-Scan-Signature: 5888f019f789bb7da964f45b5f85ee04 Subject: Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 dB1489.0 Hz Content-Type: multipart/alternative; boundary="------------040903040608030105050200" 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-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 4225 This is a multi-part message in MIME format. --------------040903040608030105050200 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Hi Luis, Am 30.09.2015 14:44, schrieb VIGILANT Luis Fernández: > Hi Stefan, MF > I have been calculating the loop area with the help of Google Earth. > Not a regular shape but counting on the known perimeter > and measures it can be estimated as 224 m2 > I detect the RF current with this circuit from G4HUP but have not > calibrated it > http://g4hup.com/RFC/RF%20Current%20Meter%20Kit%20V2_0.pdf > I don't use the meter and R3, VR1, VR2 and directly wire down the > shack the output from rectifier diode and use an analog > voltmeter. The transformer is made in the same way with a ferrite > clamp over loop wire and 10 turns as secondary > The 2x100R load was using 1/2w resistors and burned out when using the > PA. So changed them to 2x5W resistors > On the volmeter I can get 60V dc when the antenna is tuned (minimum PA > DC current). The 5W resistors still stand ! Minimum PA DC current? Not maximum? 60V DC at 50 Ohm across 2x 5W resistors? I think i do misunderstand something. Hm, maybe it's better to use 40 turns secondary instead of 10. No need to waste power :-) In a loop there are of course much higher currents then in a vertical antenna... > I'm using 800pF fixed caps and 490pF variable at about mid value to > resonate the loop. Bandwith is sharp but lets me work > WSPR and Opera. So lets assume 3KHz > Have changed some parameters in Andy's Excel. Sized it down as a 17m > diameter loop to match 224m2 loop area > Power down to 75W which is what I get with PA under 50ohm. Conductor > diameter 5mm, not 6mm (great difference) > And it reports 1dBW ERP with 11A and 2904V > Can it be that high ? No. 1 dBW is 1.26 W. This is not possible with such a loop and 75W. And this is why i personally prefer to avoid simulations and do measurements instead, during transmitting at that time. :-) 73, Stefan > Probably less due to mismatch in the feeding transformer > Nice ERP but in the wrong direction, I'm afraid :( > 73 de Luis > EA5DOM > > ------------------------------------------------------------------------ > *De:* owner-rsgb_lf_group@blacksheep.org > [mailto:owner-rsgb_lf_group@blacksheep.org] *En nombre de *DK7FC > *Enviado el:* miércoles, 30 de septiembre de 2015 13:25 > *Para:* rsgb_lf_group@blacksheep.org > *Asunto:* Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 > dB1489.0 Hz > > Hi Luis. > > What is the loop RF current and the loop area? Do you know it? > Is it problematic to match the loop? You just need a C and a ferrite > transformer. If you have such a relatively high perimeter, you > probably need about 1 nF to resonate it? Currents may be in the range > of 10A at 100W? A bandwidth of maybe 3 kHz? > > 73, Stefan > > Am 30.09.2015 11:14, schrieb VIGILANT Luis Fernández: >> Hi MF >> Probably not 2mW ERP Stefan ;-) >> Have to reconfigure my U3 but really don't know which ERP I'm getting >> right now >> The PA outputs 60V RMS under 50Ohm load, but the loop is not an ideal >> load and I can tune it >> to about 80V RMS. When detuned, RMS runs up to >>100V and PA gets >> into problems >> I tried to get loop performance using Andy G4JNT excel and this is >> what I got >> https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/70m%20MF%20Loop%20at%20100W%20.png >> Probably many things wrong there >> What I use is a 70m perimeter loop made from RG59 coax (braid and >> inner shorted on ends) but not a round circle >> The resonate cap is very close to what I need to tuneit. So the >> "equivalent" round loop diameter should be 21m >> Go figure ! :-) >> One detail to mention: >> Yesterday, it rained. Not very usual here and still not tested the >> loop with this Tx power and with wet terrace >> It seems to me that my signals was better than before. Could the wet >> terrace worked as a kind of reflector or >> re-shapped the radiation diagram of the horizontal loop making it >> more efficient for Dx ?? >> The loop is not equidistant from terrace but keeps about 3 to 4 meter >> high, and just 1m on the feeding point >> 73 de Luis >> EA5DOM >> >> ------------------------------------------------------------------------ >> *De:* owner-rsgb_lf_group@blacksheep.org >> [mailto:owner-rsgb_lf_group@blacksheep.org] *En nombre de *DK7FC >> *Enviado el:* miércoles, 30 de septiembre de 2015 10:18 >> *Para:* rsgb_lf_group@blacksheep.org >> *Asunto:* Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 >> dB1489.0 Hz >> >> Hi Luis, >> >> Ooh, very well! I'm glad that i received you the first time! Is it >> really 2 mW ERP? >> Oh and BTW it was in WSPR, the super mode!!!! ;-) >> >> 73, Stefan >> >> Am 30.09.2015 00:17, schrieb VIGILANT Luis Fernández: >>> Even with the loop we are on the way ;-) >>> >>> 2015-09-29 22:00 EA5DOM 0.475611 -27 0 IM98wn 0.002 >>> DK7FC/P JN49ik 1398 27 >>> >>> >>> 73 de Luis >>> EA5DOM >>> ------------------------------------------------------------------------ >>> *De:* owner-rsgb_lf_group@blacksheep.org >>> [owner-rsgb_lf_group@blacksheep.org] en nombre de DK7FC >>> [selberdenken@posteo.de] >>> *Enviado:* lunes, 28 de septiembre de 2015 21:47 >>> *Para:* rsgb_lf_group@blacksheep.org >>> *Asunto:* Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 >>> dB1489.0 Hz >>> >>> >>> Am 28.09.2015 17:02, schrieb VIGILANT Luis Fernández: >>>> [...] >>>> Next in the list is going vertical. Coil and variometer on the way. >>>> Keep tuned ;-) >>>> 73 de Luis >>>> EA5DOM >>>> >>> >>> Oh yes! Do it!!! :-) Looking forward to a QSO :-) >>> >>> 73, Stefan --------------040903040608030105050200 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi Luis,

Am 30.09.2015 14:44, schrieb VIGILANT Luis Fernández:
Hi Stefan, MF
 
I have been calculating the loop area with the help of Google Earth. Not a regular shape but counting on the known perimeter
and measures it can be estimated as 224 m2
 
I detect the RF current with this circuit from G4HUP but have not calibrated it
I don't use the meter and R3, VR1, VR2 and directly wire down the shack the output from rectifier diode and use an analog
voltmeter. The transformer is made in the same way with a ferrite clamp over loop wire and 10 turns as secondary
The 2x100R load was using 1/2w resistors and burned out when using the PA. So changed them to 2x5W resistors
On the volmeter I can get 60V dc when the antenna is tuned (minimum PA DC current). The 5W resistors still stand !
Minimum PA DC current? Not maximum? 60V DC at 50 Ohm across 2x 5W resistors? I think i do misunderstand something.
Hm, maybe it's better to use 40 turns secondary instead of 10. No need to waste power :-)
In a loop there are of course much higher currents then in a vertical antenna...

 
I'm using 800pF fixed caps and 490pF variable at about mid value to resonate the loop. Bandwith is sharp but lets me work
WSPR and Opera. So lets assume 3KHz
 
Have changed some parameters in Andy's Excel. Sized it down as a 17m diameter loop to match 224m2 loop area
Power down to 75W which is what I get with PA under 50ohm. Conductor diameter 5mm, not 6mm (great difference)
And it reports 1dBW ERP with 11A and 2904V
 
Can it be that high ?
No. 1 dBW is 1.26 W. This is not possible with such a loop and 75W. And this is why i personally prefer to avoid simulations and do measurements instead, during transmitting at that time. :-)

73, Stefan

Probably less due to mismatch in the feeding transformer
 
Nice ERP but in the wrong direction, I'm afraid :(
 
73 de Luis
EA5DOM 

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de DK7FC
Enviado el: miércoles, 30 de septiembre de 2015 13:25
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 dB1489.0 Hz

Hi Luis.

What is the loop RF current and the loop area? Do you know it?
Is it problematic to match the loop? You just need a C and a ferrite transformer. If you have such a relatively high perimeter, you probably need about 1 nF to resonate it? Currents may be in the range of 10A at 100W? A bandwidth of maybe 3 kHz?

73, Stefan

Am 30.09.2015 11:14, schrieb VIGILANT Luis Fernández:
Hi MF
 
Probably not 2mW ERP Stefan ;-)
 
Have to reconfigure my U3 but really don't know which ERP I'm getting right now
The PA outputs 60V RMS under 50Ohm load, but the loop is not an ideal load and I can tune it
to about 80V RMS. When detuned, RMS runs up to >>100V and PA gets into problems
 
I tried to get loop performance using Andy G4JNT excel and this is what I got
 
Probably many things wrong there
What I use is a 70m perimeter loop made from RG59 coax (braid and inner shorted on ends) but not a round circle
The resonate cap is very close to what I need to tuneit. So the "equivalent" round loop diameter should be 21m 
Go figure ! :-)
 
One detail to mention:
Yesterday, it rained. Not very usual here and still not tested the loop with this Tx power and with wet terrace
It seems to me that my signals was better than before. Could the wet terrace worked as a kind of reflector or
re-shapped the radiation diagram of the horizontal loop making it more efficient for Dx ??
 
The loop is not equidistant from terrace but keeps about 3 to 4 meter high, and just 1m on the feeding point
 
73 de Luis
EA5DOM

De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de DK7FC
Enviado el: miércoles, 30 de septiembre de 2015 10:18
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 dB1489.0 Hz

Hi Luis,

Ooh, very well! I'm glad that i received you the first time! Is it really 2 mW ERP?
Oh and BTW it was in WSPR, the super mode!!!! ;-)

73, Stefan

Am 30.09.2015 00:17, schrieb VIGILANT Luis Fernández:
Even with the loop we are on the way ;-)

 2015-09-29 22:00   EA5DOM   0.475611   -27   0   IM98wn   0.002   DK7FC/P   JN49ik   1398   27 

73 de Luis
EA5DOM
De: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] en nombre de DK7FC [selberdenken@posteo.de]
Enviado: lunes, 28 de septiembre de 2015 21:47
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: Re: 23:35 477 EA5DOM de EB3FRN Op8 Deep Search -36 dB1489.0 Hz


Am 28.09.2015 17:02, schrieb VIGILANT Luis Fernández:
[...]
 
Next in the list is going vertical. Coil and variometer on the way. Keep tuned ;-)
 
73 de Luis
EA5DOM


Oh yes! Do it!!! :-) Looking forward to a QSO :-)

73, Stefan
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