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

Re: actuator
by Edward Cole 28 May '07

28 May '07

At 01:45 AM 5/28/2007, w7lrd(a)comcast.net wrote: >Hello >Has anyone tried an actuator for an elevation? I have checked out- >http://www.qsl.net/sv1bsx/actuator/actuator.html >I want to add a four foot primestar to what I already have (2M 70M >and a 36x30 primestar dish. With all this hardware I will be over >working my g5400. I would probably have to replace the split >fiberglass boom with a longer metal one. Then we get into the old >metal vs insulated boom.I have some old 'C' band receivers that have >actuator controls in them. > Bob, Actuators are in common use for elevation with eme antennas (yagi arrays and dishes). I use an actuator for elevation of my four M2-xpol-20 x-yagis (each 21-foot long booms), plus I have two 12-foot 1296 and one 7-foot 902 loop-yagis mounted inside the array. The H-frame is 3" diam. 12-foot long cross-boom with 12-foot long 1.5" riser masts with fiberglass tips. The elevation bracket weighs 70-lbs. Total weight is probably well over 100-lbs. and the actuator handles it easily. Lots of wind area in this 12x12x 21 foot mess. On my satellite setup I use a 6-foot aluminum cross-boom (2m KLM-22C; 70cm 435CP42) plus a 33-inch offset feed dish for 2.4 GHz. No problems with use of metal cross-boom with antennas mounted in the "X" configuration (and feedline tied tight to boom and cross-boom). I would eliminate the elevation part of the G5400 if you decide on an actuator. In fact, before I got my B5400 I was using an used actuator arm on my satellite antennas (2m&70cm x-yagis). Only caveat is that the actuator moves slowly and may not be fast enough to track Leos in overhead passes (I haven't actually made any calculation on this, though). 73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa(a)hotmail.com ======================================

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Thanks
by w3vvp 28 May '07

28 May '07

Thanks to everyone who replied to my last email on no help. For over 50 years I repaired radios mine and other peoples. Now due to age and a handicap I have to ask for help.SRI if I offened any one with my last post.George W3VVP

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actuator
by w7lrd＠comcast.net 28 May '07

28 May '07

Hello Has anyone tried an actuator for an elevation? I have checked out- http://www.qsl.net/sv1bsx/actuator/actuator.html I want to add a four foot primestar to what I already have (2M 70M and a 36x30 primestar dish. With all this hardware I will be over working my g5400. I would probably have to replace the split fiberglass boom with a longer metal one. Then we get into the old metal vs insulated boom.I have some old 'C' band receivers that have actuator controls in them. -- 73 Bob W7LRD AMSAT member 28498 Seattle

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CP4 return 5 min. interval
by Mineo Wakita 28 May '07

28 May '07

CP4 returned to 5 minutes interval. de JE9PEL, Mineo Wakita

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2M1EUB/P
by paul robinson 28 May '07

28 May '07

2M1EUB/P NOW QRV FROM IO87RJ ON ALL SATS! FOR 7 DAYS. --------------------------------- Yahoo! Answers - Got a question? Someone out there knows the answer. Tryit now.

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No Help
by w3vvp 28 May '07

28 May '07

What has happened to amateur radio? A week ago I put out a request for help for my 736R which I use for satellite work. As of this date I have received zilch,0,nothing in reply. Are there no more ham repair people out there or is everybody an appliance operator???? George W3VVP

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RAFT Fence Doppler Plot Posted
by Robert Bruninga 28 May '07

28 May '07

RAFT-REENTRY CAMPAING web page now has a Doppler Plot against TIME: http://www.ew.usna.edu/~bruninga/craft/save-raft.html To our surprise, the RAFT XP-217 radar receiver hears the Radar sidelobes as long as it is above the horizon! I guess that makes sense for a 700 KW transmitter. Even if we are not in the 80 Meggawatt main beam, the radar receiver does still hear it (even though its RX sensitivity was intentially only designed to be only - 40 dBm? or so)... Now, is there anyone on the AMSAT-BB that would like to analyze this portion of the Doppler Plot and prove the timing. The only thing I'd like to confirm is the added inflection point at the start (probably due to the bistatic radar situation) which makes this different than the usual "S" plot with only a 3rd order curve. Bob WB4APR > -----Original Message----- > From: Robert Bruninga [mailto:[email protected]] > Sent: Monday, May 28, 2007 12:26 AM > To: bruninga(a)usna.edu; rx217(a)alum.WPI.EDU; 'Matt Bennett' > Cc: 'Lauret & Henk'; 'Ron Hashiro'; 'Dieter Schliemann'; > mail(a)mike-rupprecht.de; iana(a)kcbbs.gen.nz; > k.swaggart(a)charter.net; jf1aje(a)aprs.xii.jp; > veillet(a)cfht.hawaii.edu; tanimoto(a)hawaii.rr.com; > ah6gr(a)arrl.net; dquagliana(a)aol.com; hhm_74115(a)cox.net; > walterh(a)k5wh.net; crabtrej(a)erau.edu; wa6lie(a)msn.com; > ea4ekh(a)telefonica.net; zl2cia(a)amsat.org; > geoff.clark(a)clear.net.nz; matsu(a)aje.jpn.org; ei7m-wkt(a)asahi-net.or.jp > Subject: RAFT Voice may notebe fully set? > > I blew my pass. > > It arrived about on schedule (Keps dated 27th at 1313z.) > At first I got no response to my LOGGON attempt. SO I assumed > that the southern stations attempts had locked me out. So I > forced a disconnect so that I could reconnect to RAFT and at > least check out the voice. > > That was successful, but then I saw the earlier password > challenge coming back. At this time I was no longer connected > and didn't have time to re-sequencce everyting. > > SO my commaindng was a failure due to cockpit error. > > BUT when I CONNECTed RAFT, the VOICE came up just fine, but did > NOT speak any packets sent to it. So I wonder if all settings > are correct. Maybe the European or other command stations not > in the footprint of the Southern USA FENCE could logon and SET > these settings: > > MYAPRS TALK > MXMIT ON > > It is clear that the others ARE set OK, since CONNECTing RAFT > does bring up the voice transponder. SO these are OK and do not > need to be confirmed. > > CTR A OFF > CONOK ON > CMSG OFF > > But if MYAPRS TALK is not set or if MXMIT ON is not on, then the > voice module will not speak APRS messages... > > Bob, WB4APR > >

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Re: Horizontal Polarized Antenna
by Sion Chow Q. C. (9W2QC) 27 May '07

27 May '07

Dear All, Thank you for all the replies regarding this subject. By mounting the antennas horizontally will save me a lot of trouble, so I guess this is the way I will go. Once again, thank you for all the replies, it is really appreciated and my apologies for not getting back to each message individually. 73, Sion Chow Q. C., 9W2QC. > -----Original Message----- > From: Jim Jerzycke [mailto:[email protected]] > Sent: Friday, May 25, 2007 11:42 PM > To: Sion Chow Q. C. (9W2QC) > Subject: Re: [amsat-bb] Horizontal Polarized Antenna > > I use my "terrestrial" horizontal 2M/70cm antennas and > my FT-847 to work the satellites and the ISS, and > other than not being able to use the higher elevation > passes, they work fine. I have an M2 7 element 2M, and > an M2 11 element 70 cm antenna on a 5' tripod, mount > to the roof of a large 2 story commercial building. I > have a clear view over 360*, and if I can hear the > satellite, I can get in to it. > Jim KQ6EA > > --- "Sion Chow Q. C. (9W2QC)" <9w2qc(a)9w2qc.net> wrote: > > > Dear All, > > > > Currently for my satellite station I am using double > > stacked vertical > > polarized yagi antennas for 2M and 70 CM. > > > > However, due to mounting constrains, I would like to > > mount them in a H > > configuration instead, on the G-5500 rotator, with > > the 2M antenna on one > > side and the 70 cm antenna on the other. A yagi for > > L and S band will be > > mounted in between the two antennas on the > > horizontal boom. > > > > This would mean that I will require the antenna to > > be horizontally polarized > > instead of vertically polarized unless I use a > > non-metallic boom. Before I > > perform this, I would like to know what are the > > differences with using > > horizontal instead of vertical polarization when > > operation the LEOs such as > > AO-51, SO-50 and etc. Also, what are the effects of > > using a horizontal > > polarization with the ISS on 2M? > > > > Sorry if this has been asked before, but was just > > trying to be sure before I > > perform any major modifications. Thank you very > > much in advance. > > > > 73, > > Sion Chow Q. C., > > 9W2QC. > > > > > > > > _______________________________________________ > > 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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PCSAT coming back first half of June?
by Joe Veldhuis 27 May '07

27 May '07

According to my tracker, PCSAT will be in full sunlight from June 2 to June 16, based on the latest keps from Spacetrack. As I understand it, the batteries on this satellite are very weak, and will not hold enough charge to support transmitting if it's eclipsed for too long, but given enough sun it is usable. This is an excellent bird when it's operational, every bit as easy to work as the ISS digipeater was, so I'm looking forward to filling in a few grids with it over the next few weeks using my modest ground station. -Joe, N8FQ Grand Haven, Michigan EN62wx

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SUCCESSFUL RAFT Transponder Activation!
by Matt Bennett 27 May '07

27 May '07

Hi All, On the 0600 UTC western pass this morning (5/27), the UCISAT ground station crew successfully activated RAFT's radar transponder as it approached the Texas radar fence! After several days of unsuccessful attempts, the success of this pass was largely attributed to NORAD obtaining a fresh set of Keps for RAFT's degrading orbit just before the pass started. The epoch of the elset was less than 3 hours, so our pointing was much more accurate than in previous low EL passes. I threw together a simple website with the audio recording files and audio spectrum analysis of the transponder tone from the successful pass. The site also has tips and tricks for operators who want to help record the transmission within the footprint: http://ucisat.eng.uci.edu/RAFT.php According to Bob Bruninga (WB4APR), the audio recording on the website is in fact the transponder picking up the ground radar signal. However, he pointed out that we did not catch the narrow beam of the radar which would have sounded like a bird chirp in the middle of an open FM carrier. He believes this could be because RAFT may have been too far west of the radar station and only catching side lobes, or because the transponder was activated a bit too early (difficult to tell due to a last minute configuration change at our station to accommodate the new elset). Because of this uncertainty, we absolutely need additional operators within the eastern and western pass footprints to help record the transponder audio!! For the next couple of days, two command stations will activate the transponder just before the radar fence penetration on the eastern and western passes around 0400 and 0530 UTC respectively. These times are MUCH earlier than they were at the beginning of last week because of the orbit decay (no longer 2-4 AM). Plus, all you have to do is record the audio! If you're interested, a procedure for recording stations willing to volunteer on the website above. For specific info on RAFT and its mission/operations, please see their website at http://www.ew.usna.edu/~bruninga/craft/save-raft.html Please feel free reply with questions if you're interested in helping with the recording in the next few days and one of us will get back to you. Thanks again to all for your reports and support throughout this week! 73, Matt Bennett KF6RTB ____________________________________________________________________________________Need a vacation? Get great deals to amazing places on Yahoo! Travel. http://travel.yahoo.com/

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