August 2007 - AMSAT-BB - mailman.amsat.org

Re: Fw: Re: 70cm Parasitic Lindy
by i8cvs 22 Aug '07

22 Aug '07

----- Original Message ----- From: "Anthony Monteiro" <aa2tx(a)comcast.net> To: "i8cvs" <domenico.i8cvs(a)tin.it> Sent: Wednesday, August 22, 2007 4:46 PM Subject: Re: Fw: [amsat-bb] Re: 70cm Parasitic Lindy > Hello Domenico, > > Nice to hear from you! Unfortunately, I do not understand > Spanish. I could tell that you were commenting about the BALUN > but not enough to really understand it - I am sorry. > > 73, > Tony AA2TX Hi Tony, AA2TX About a simple balun for your Parasitic Lindy I was trying to say you that a balun-bazuka for 435 MHz with a ratio 1/1 can be made as follows: Slip 81 mm of coax braid over the PVC jacket of your feed line and live this braid open and insulated at the point in wich the feed line connects to the open dipole. Cut and remove a small ring of PVC jacket from your feed line at a distance of 81 mm from the studs of the open dipole. Solder the other end of the 81 mm braid all around the ring of the exposed braid of your feed line and protect this soldered point from water using a heat-shrink tubing. The braid slipped over the PVC jacket of your feed line is made 81 mm long because the dielectric constant of PVC II or Vinil Polychlorure is ranging between 4 to 5 depending of the jacket type so that considering an average value of 4.5 for the dielectric constant the velocity factor for PVC is Vf= 1/(SQR 4.5 ) = 0.47 It follow that for 435 MHz a quarter electrical wavelenght balun-bazuka made of a braid slipped as a tubing over the PVC jacket of a coax feed line is long 300/435/4 * 0.47 = 81 mm >From the electrical point of view call I1 the RF current flowing over the inner conductor of your feed line connected to one arm of the open dipole. Without using a balun-bazuka the current I2 flowing over the inner surface of the braid of your feed line as soon arrive to the other arm of the dipole divide itself in two parts. I4 is the current that flow in to the arm of the dipole and I3 is the current that flow back to the generator traveling over the outside surface of the braid of your feed line and is badly radiated by the line itself but in any case I2=I3+I4 Using instead the mentioned quarter wave balun-bazuka the current I3 after flowing back over the outside surface of the braid of the feed line get a short circuit after 81 mm from the dipole and it is completely reflectet back to the dipole so that I3 cannot be radiated by the feed line and the currents flowing in both arms of the dipole are equals and balanced i.e. I1=I2 I am confident that this type of balun-bazuka 1/4 wavelenght long is much better than using ferrite beads slipped directly over the jacket of the coax cable. For more information on this type of balun-bazuka read Walter M. Maxell W2DU book "REFLECTIONS Transmission Lines and Antennas " Best 73" de i8CVS Domenico

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Re: TS-2000 birdie
by Eddy GORA 22 Aug '07

22 Aug '07

I admit I don't knew nothing abt. birdies but I never thought Kenwood can sell this kind of radio for that amount of money. This is disrespect for customers, I paid 2700 EUR few months ago. Actually I don't bought this radio for satellite, just as "best money can buy" compared to all features inside. I use mostly on VHF & up ( so comments are for that part ) and I discovered after using abt. 2 years ( I had several TS-2000 ) many bad implemented functions like SUB-RX, NB function, birdies... I don't say it's bad, but for sure 2700 EUR in YO ( in January 2007 ) are far away from reality for this radio. I consider now, TS-2000 worth only for a very good modulation, very good thermal management and quite good front panel compared to let's say 857 of 897 from Yaesu ( of course, except 7-800 EUR 23cm band module and power increased ). Since I am only interested on VHF&up DX, I really consider to buy a good SW one and a decent transverter. Best regards, 73, YO3HCV Sorry to hear that you found out after you bought the rig. It is a well known problem and Googling "ts 2000 birdie" will find 5 hits. Despite this, I have one and it is still a great rig. Jack Swart Sydney, Australia -- VK2TRF QF56oe P5 or nothing No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.484 / Virus Database: 269.12.1/965 - Release Date: 8/21/2007 4:02 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.484 / Virus Database: 269.12.1/965 - Release Date: 8/21/2007 4:02 PM

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TS-2000 birdie
by Eddy GORA 22 Aug '07

22 Aug '07

Hi everyone, As I spoke with some friends G0SFR, YO3GCF, I just checked today my TS-2000 for any "birds" on 70cm band. My transceiver it's brand new TS2000X, european version, fabricated in October 2006. Checked in USB mode ( make your corrections for FM ), finest step possible, 50 Ohm dummy load. This are results on claimed frequencies and intensity if applicable : 435.862 - S0 - almost perceptible, but present 436.799 - S9 - very strong, I can't imagine how Kenwood sell this TVCR ! When the SUB receiver it's active, there are several S9+60 signals from each other MAIN-SUB. SUB receiver it's only for talking around, at least on 2m, has a lot of inter-modulations and cross-modulations. In fact, schematic performs quite well, just the design it's bad (watch the SUB FM demodulator and front-end, like an ordinarily PMR radio). 73 de Edi, YO3HCV No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.484 / Virus Database: 269.12.1/965 - Release Date: 8/21/2007 4:02 PM

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70cm Parasitic Lindy
by Anthony Monteiro 21 Aug '07

21 Aug '07

At 05:00 AM 8/19/2007, John Heath wrote: >Hi Tony, > >Thanks for publishing the 2m design for your para lindy. >I will be building one to pair up with my 70cms version. > >I had several e-mail asking where to download the 70cms design. >Is it accesible on the net antwhere? ><http://www.amsat.org>www.amsat.org would be a good place. > >73 John G7HIA Hi John, Ron Porter, K5AI was kind enough to convert it to a pdf and put it on his web site. Anyone who wants it can get it here: http://www.qsl.net/nwlarn/sat/70ParaLindy.pdf This is from the 2006 AMSAT Space Symposium. 73, Tony AA2TX

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SATPC32 Compatibility with TrakBox
by John Kopala 21 Aug '07

21 Aug '07

Does anybody know if SATPC32 supports the terminal interface with a TrakBox for antenna positioning? Thanks, John Kopala N7JK

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Attention - Chris Weaver.
by Dave Aitch 21 Aug '07

21 Aug '07

Need your address to send you the KCT/T please Chris. Tried your direct e-mail address but no replies. Cheers, Dave.

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Re: AO-7 log proposal.
by w7lrd＠comcast.net 21 Aug '07

21 Aug '07

Hello- Many times I'll tell the XYL,"I'll be in lthe ham shack". Four hours later I'll "surface". She'll say, "who did you talk to"? No one I reply, but I had a blast! Activity does not necessarily you hit the PTT switch. 73 Bob W7LRD Seattle -------------- Original message -------------- From: "John Hackett" <archie.hackett(a)hotmail.com> > To whom it may concern, > I propose that the statistics system of > the AO-7 Resource Page log be modified somewhat. > > Namely ... that the scorecard *NOT* give points when no actual QSO takes > place. > > Further ... that the minimum requirement should be an exchange of signal > report and locator for a > 'valid' QSO to be added to the scorecard. > > The reason that I propose this change is that one particular station has > claimed 34 points in the last 7 days without having conducted one single QSO > .... which makes a mockery of the current scorecard system. > > While the log was originally intended as an ACTIVITY log ... there are many > stations who appreciate the scoring system ... thereby adding to the > 'challenge' ... and increasing their awareness of the need for good > operating proceedures as well as improving their receiving capabilities. > > It is unfair that these stations be surpassed by others who don't even have > a QSO via the satellite. > > That is why I propose a modification of the scoring system ... ie ... no QSO > = no points. > > Opinions, comments and 'flaming' to me please, preferably on the back of a > $100 note though an e-mail will suffice ... (at a pinch). > > 73 John. AO-7 Resource Page Log Admin: > > > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

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AO-51.
by John Hackett 21 Aug '07

21 Aug '07

Hello folks, Not having worked an FM satellite for about 10 years I'm wondering if there's any activity over Europe on AO-51. I've worked various analogue satellites every day for the last 17 years but havn't listened to or worked AO-51 "live" ... though I have listened to it while it was over California ... (while connected to N1DID on Echolink). I recently borrowed an IC-E91 D-Star handheld and thought of giving AO-51 a try. My QTH on Frei Island doesn't lend itself to ISS passes but according to InstantTRACK AO-51 does occasionally pass within spitting distance of me .... but do the Europeans work this satellite?. Any comments would be very much appreciated. 73 John. <la2qaa(a)amsat.org>

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LZ/G0SFJ and YO/G0SFJ report
by andy thomas 21 Aug '07

21 Aug '07

As previewed here and on Radio Bulgaria International's DX programme, G0SFJ operated with an Arrow and a FT51-R from LZ and YO these last few days. My records show: >From Belite Brezi (see: http://www.astro-brezi.org, LZ, KN21nn, on 12 and 13/8 on AO51: G7HIA 9H1FF F6CDZ G0VHS PD1DRE SW1IXP OZ1MY DG9YIB >From the European circle (monument) in Herastrau Park, Bucharest,(see: http://bruxelles.mae.ro/pdf/Romanian%20Headlines%20no.%208.pdf paragraph 24) YO, KN34al on 18/8: IW0DTK and in the evening outside Bucharest in a sunflower field, KN34bq ON5SA (mostly) Also I heard G8ATE and GB1PBL and called both Dave and Robert but they were low on my horizon and talking to each other! Observations 1. I found out in the manual that my FT51R reduces tx power when the case gets hot (repeated useage on 5 watts) and I think this was a problem after mid pass. Lesson: do not use up power (and heat!) on the only alligator on the satellite Northbound (you know who you are - on reflection, you probably don't!)! Certainly, temperatures in YO were in the high 30s (Centigrade) for most of the day, and this could mean it would heat up quicker. Maybe I'll fit a small Peltier device to the case? 2 I found it difficult to switch on SO-50 in the mornings and the night passess were after 2300 local and in pitch dark, so I'm afraid I abandoned SO-50. It might be that I was simply on the wrong rx frequency if it is changeing from expected. 2 A pleasure to meet Victor YO3HQN, Eddy YO3HCV and Dragos YO3GCF. I hope at least one of them will appear soon with an Arrow?HT on AO51... All passes tape recorded. I will QSL direct or via bureau and some pictures of the operation will appear in due course on http://www.andythomas.eu 73 and thanks again to the AO51 command crew and G0SFJ ___________________________________________________________ Want ideas for reducing your carbon footprint? Visit Yahoo! For Good http://uk.promotions.yahoo.com/forgood/environment.html

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AO-7 log proposal.
by John Hackett 21 Aug '07

21 Aug '07

To whom it may concern, I propose that the statistics system of the AO-7 Resource Page log be modified somewhat. Namely ... that the scorecard *NOT* give points when no actual QSO takes place. Further ... that the minimum requirement should be an exchange of signal report and locator for a 'valid' QSO to be added to the scorecard. The reason that I propose this change is that one particular station has claimed 34 points in the last 7 days without having conducted one single QSO .... which makes a mockery of the current scorecard system. While the log was originally intended as an ACTIVITY log ... there are many stations who appreciate the scoring system ... thereby adding to the 'challenge' ... and increasing their awareness of the need for good operating proceedures as well as improving their receiving capabilities. It is unfair that these stations be surpassed by others who don't even have a QSO via the satellite. That is why I propose a modification of the scoring system ... ie ... no QSO = no points. Opinions, comments and 'flaming' to me please, preferably on the back of a $100 note though an e-mail will suffice ... (at a pinch). 73 John. <la2qaa(a)amsat.org> AO-7 Resource Page Log Admin:

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