February 2010 - AMSAT-BB - mailman.amsat.org

AO-51 Signal Strength Post Flip
by John Papay 10 Feb '10

10 Feb '10

It has been about a month now since AO-51 was commanded back to its normal orientation. But many are reporting that they are having more trouble hearing it now than they did before the first re-orientation. It does seem to me that some stations that usually hear very well are not hearing that well now. This morning's pass (9Feb2010 1045z) of AO-51 seemed to bear that out. AF6RF, KB1RVT, KE3LB, WD0X?, KJ4CBC, K5QXJ, WB2IOL and YF6BFE were on the pass and with a few exceptions, all were not able to hear at some point during the pass. There are also a few noisy uplink transmissions as well. The recording can be downloaded at: http://www.papays.com/AO-51_09Feb2010_104452za.mp3 (there are no signals in the first minute of the recording) Is anyone else having trouble hearing AO-51 as well as they heard it before the flip experiment? 73, John K8YSE

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Office Closed
by Martha 10 Feb '10

10 Feb '10

Due to blizzard conditions today, the AMSAT office is closed. -- 73- Martha

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Down East Microwave 2355LYK 1.2GHz 55 elements loop antenna
by Juan Antonio Fernandez 10 Feb '10

10 Feb '10

Have anyboy worked with this 55 elements loop antena for 1.2 GHz. What about its mechanical and electric features? Juan Antonio EA4CYQ

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Good Night, Loran
by Howie DeFelice 10 Feb '10

10 Feb '10

Minor clarification, Loran-A was used from WW-2 until it was turned off in the 1980's I believe. The current system, Loran-C was in commercial use starting in the late 70's. When Loran-C was used for returning to a previously stored waypoint, it's accuracy was almost as good as current GPS and better than the early "dithered" commercial GPS service. Howie AB2S _________________________________________________________________ Your E-mail and More On-the-Go. Get Windows Live Hotmail Free. http://clk.atdmt.com/GBL/go/201469229/direct/01/

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Re: New Lindy's QRV
by Clint Bradford 09 Feb '10

09 Feb '10

I read that article, and when I got to the last of it and he mentioned that he was using a pre-amp for working the FM birds, I wondered out loud: "Why???" We're working '27, '50, and '51 with HTs and meager antenna improvements. Better yet, build a tape measure Yagi - you can realize great gain with about six bucks of parts. Note that I haven't mentioned, "Buy a pre-amp" anywhere. I was considering building one of those antennas mentioned in QST last month - until I read that he was using a pre-amp. I'll just stick with what works for me ... home-brew or commercial Yagis ... a log periodic every now and then ... and no pre-amp anywhere. Clint, K6LCS http://www.work-sat.com

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Re: New Lindy's QRV
by Clint Bradford 09 Feb '10

09 Feb '10

>> ... Does it -matter- if he uses a preamp on FM, SSB, or freaking two cans and a string? Absolutely not. It has just been my "mantra" the past four years advising folks that you do not need 100 Watts of TX power, expensive Yagis on the roof, and a rotator under computer control to get into working the FM satellites. Now, then, if I lived in Drew's neighborhood, all that equipment sounds pretty appealing ... working the birds while adding fire to the fireplace with a hot toddy (or three) at hand. Clint, K6LCS

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Good Night, Loran
by Clint BRADFORD 09 Feb '10

09 Feb '10

In a series of small ceremonies, the U.S. Coast Guard on Monday shut down Loran-C, a navigation and timing system that has guided mariners and aviators since World War II. The death blow came last May when President Obama called the system obsolete, saying it is no longer needed in an age in which Global Positioning System devices are nearly ubiquitous in cars, planes and boats. Killing Loran-C will save the government $190 million over five years, Obama said. But supporters of Loran -- including the man known as "the father of GPS" -- say the nation's increasing reliance on GPS paradoxically has increased the importance of maintaining Loran as a backup. At 3 p.m. Monday, the U.S. Coast Guard turned off Loran signals at 19 of the 24 Loran stations. Signals remain at five stations because of agreements with Russia and Canada, but the Coast Guard expects those stations to be decommissioned by June after the United States receives verification that those countries have been notified of the change. The five stations that temporarily remain on line are at Attu, in Alaska's Aleutian Islands, and Caribou, Maine; Nantucket, Massachusetts; Shoal Cove, Alaska; and George, Washington. - from CNN/Reuters Clint Bradford, K6LCS

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Re: John's take on AO-51
by Robert Smith 09 Feb '10

09 Feb '10

Aloha All In general, Hawaii is a very quiet place. Most passes of AO-51 fly by with no usage. Accordingly, signal strength and quality are usually quite discernable (assuming no anomalous QRM) when QSOs do occur. The initial reorientation of AO-51 was very apparent here. In general, the bird appeared to have less signal strength and more fades. It was, SO-50 like. Since reorientation, it is my impression that the signal strength has improved significantly but there remain some fades; especially at lower elevations. In discussions with KG6NUB and others, the feeling is that the bird is still in some kind of "recovery mode." To me, "51" now seems like its old "self." Fades are becoming less prevalent. Finally, my knowledge regarding orientation, reliability and stability of OSCAR satellites is extremely limited. The concept of "recovery" may not even be applicable. Perhaps the AO-51 team can shed some light on the results of the overall experiment. 73 and Aloha to all. Respectfully, robert NH7WN, Honolulu

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Re: New Lindy's QRV
by Bill Dzurilla 09 Feb '10

09 Feb '10

Dave, I would be suspicious of the construction. I can get a few minutes of good copy from AO-51 on a high pass with just a rubber duck on an HT. If you do get a preamp, the run between the antenna and the preamp is critical, so if possible keep it short and use good coax. Ed seems to be having success with 4' of RG-58U, but generally the use of any RG-58U at 70cm is not a good idea. Here's a quick summary of my results with various antennas: * HT and rubber duck or other antenna mounted directly on the HT - success only at high elevations * HT and Arrow or Elk antenna, no preamp - success from horizon to horizon, if no trees or other obstructions * base rig and dual band omnidirectional ground plane, no preamp, 40' of RG-213U - success on most birds only when elevation is above 25-35 degrees * base rig and dual band omnidirectional ground plane, ARR preamp, 40' of RG-213U - success on most birds when elevation is above 15 degrees * base rig and Elk antenna on 12' pole at 15 degrees fixed elevation, azimuth rotation with old TV antenna rotor, ARR preamp, 70' coax run (my current setup) - full success from horizon to horizon on all birds, except in directions where blocked by trees or roof. The Elk is $135 shipped and the used rotor was $25, and this combo is by far the most effective I have used. My community has antenna restrictions, but so far no one has complained about the little 2' long Elk. The Elk could be replaced with a homebrew Cheap Yagi or tape measure yagi, which can be built for $10. I am not aware of anyone who is able to work the sats at low elevations with any type of omnidirectional antenna, even with the best preamp. You can have plenty of fun working the birds at higher elevations, but you will be able to work more passes and better DX (e.g., Europe on AO-7) if you can catch them at lower elevations. 73, Bill NZ5N > Date: Mon, 08 Feb 2010 17:26:11 -0700 > From: David Ek <dave(a)eksfiles.net> > Subject: [amsat-bb] Re: New Lindy's QRV > To: amsat-bb(a)amsat.org > Message-ID: <4B70ABA3.9090908(a)eksfiles.net> > Content-Type: text/plain; charset=ISO-8859-1; > format=flowed > > Question for anyone out there: I just built the parasitic > Lindy from the > Feb 2010 QST. What kind of performance (on receive) should > I expect from > it during, say, an AO-51 pass (max EL 83 deg)? I had my > Kenwood TH-F6a > HT connected directly to it (only a few feet of RG-8X coax > to the > antenna) with no preamp, and I only had good copy for a > moment here and > there. Just wondering if I need a preamp or if I need to be > suspicious > of my construction. > > tnx & 73, > > Dave NK0E > > ----------------- > > Edward Cole wrote: > I forgot to add that these are patterned after Tony, AA2TX, > designs > (UHF version is in Feb. 2010 QST). > My variation was to use pvc sched-40 plastic pipe (white). > > The preamp is one of the older DEMI designs that uses a > mgf-1302 > GasFet with about 0.7 dBNF. I see about one s-unit of > noise when I > turn it on. There is 4-feet of RG-58 to the UHF Lindy > and 60-feet to > the FT-847 from the preamp. The VHF Lindy has no > preamp and is fed > with 60-feet of RG-213. > > The VHF Lindy brings up repeaters 70-miles away with 50w, > and the UHF > Lindy hears repeaters that far away. So actually can > make a nice > general purpose antenna. > > 73, Ed >

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Tracking - End-stop Problem
by Clive Wallis 09 Feb '10

09 Feb '10

Hi, A problem that I've had for many years is how to track when the satellite's azimuth crosses across the rotator's end-stop, ie. when the azimuth changes from 0 to 359 degrees. My rotator turns between 0 and 450 degrees, so it should be possible to use angles between 360 and 450 to overcome a sudden transition from 0 to 360 degrees. As the pass data is available within the tracking program, it should be feasible to deal with the problem in the program. Do any tracking programs include this feature? A possible solution would be to use a small PIC between the computer and tracker, which could modify the commanded azimuth. I'm using a Yaseu 5500, LVB tracker, Sat_Explorer tracking program and WinXP. Any help, suggestions or comments would be most welcome. 73 Clive G3CWV Hitchin, North Hertfordshire, UK

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Re: New Lindy's QRV
by Clint Bradford 09 Feb '10

09 Feb '10

>> ... (Alaska ... a little inclement weather) ... The preamp makes the UHF Lindy work nearly equal with the high-price stuff...and much simpler ... I obviously didn't take your inclement weather conditions into account! A little spoiled down here in Southern California when it comes to weather ... (grin) Clint, K6LCS

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ND9M Road Trip Update #6
by claryco＠aol.com 09 Feb '10

09 Feb '10

The snowfall we received in southern Colorado last night wasn't as bad as what was predicted; we had about 4 inches overall instead of 10. Assuming southeastern New Mexico is in good "snow shape" tomorrow, we should be able to get to the DM84 / DM85 line for the AO27 pass which rises at 09/1937Z. From there, we'll head a bit southeast and be in DM74 for the next AO27 pass at 09/2116Z. Finally, AO51 should find us on the DM73 / DM83 line when it comes up at 09/2336Z. Wednesday, 10 Feb, will be a short grid day for us as we'll pull into Carlsbad, but I'll be on the DM72 / DM82 line at least for the AO27 pass at 10/2047Z; not sure about the AO51 passes later that afternoon. We expect to be in Carlsbad until Friday morning. 73, Jim, ND9M / VQ9JC Santa Rosa, NM / DM74

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FT-847 - relating dbm to S units
by Phil 08 Feb '10

08 Feb '10

Thank you for reading this. I'm still trying to determine if the aerial I have is working correctly or not. If -120 dbm for a 12 db SINAD is considered the minimum usable signal, what is the likely signal level required to indicate an S1 reading (at 435 MHz) on an FT-847 with the internal pre-amplifier turned on? The Yaesu manual quotes 0.2 micro volts for a 12 db SINAD. How many S points is likely to be? -- Regards, Phil

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Re: New Lindy's QRV
by David Ek 08 Feb '10

08 Feb '10

Well, each to their own, obviously. I've worked the birds using the Arrow antenna and an HT, and that works okay, but I secretly dream about working them from the shack instead of sitting in the back yard, and big pointable antennas are a no-no in my neighborhood. I can get away with something more discrete, like the Lindy. 73, Dave NK0E ------------------ Clint wrote: I read that article, and when I got to the last of it and he mentioned that he was using a pre-amp for working the FM birds, I wondered out loud: "Why???" We're working '27, '50, and '51 with HTs and meager antenna improvements. Better yet, build a tape measure Yagi - you can realize great gain with about six bucks of parts. Note that I haven't mentioned, "Buy a pre-amp" anywhere. I was considering building one of those antennas mentioned in QST last month - until I read that he was using a pre-amp. I'll just stick with what works for me ... home-brew or commercial Yagis ... a log periodic every now and then ... and no pre-amp anywhere. Clint, K6LCS

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Re: New Lindy's QRV
by David Ek 08 Feb '10

08 Feb '10

Question for anyone out there: I just built the parasitic Lindy from the Feb 2010 QST. What kind of performance (on receive) should I expect from it during, say, an AO-51 pass (max EL 83 deg)? I had my Kenwood TH-F6a HT connected directly to it (only a few feet of RG-8X coax to the antenna) with no preamp, and I only had good copy for a moment here and there. Just wondering if I need a preamp or if I need to be suspicious of my construction. tnx & 73, Dave NK0E ----------------- Edward Cole wrote: I forgot to add that these are patterned after Tony, AA2TX, designs (UHF version is in Feb. 2010 QST). My variation was to use pvc sched-40 plastic pipe (white). The preamp is one of the older DEMI designs that uses a mgf-1302 GasFet with about 0.7 dBNF. I see about one s-unit of noise when I turn it on. There is 4-feet of RG-58 to the UHF Lindy and 60-feet to the FT-847 from the preamp. The VHF Lindy has no preamp and is fed with 60-feet of RG-213. The VHF Lindy brings up repeaters 70-miles away with 50w, and the UHF Lindy hears repeaters that far away. So actually can make a nice general purpose antenna. 73, Ed

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Identify AO-51 Payload
by Clint Bradford 08 Feb '10

08 Feb '10

In that famous photo of the entire payload of satellites that included AO-51 (where AO-51 is at about at the 6:30 position - with that largee Italian engineering bird to its left), there's another satellite at about 02:30 that looks exactly like AO-51 (size and visible panels are alike). Whose satellite is that? Clint Bradford, K6LCS 909-241-7666

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HO68 Pass
by Edward Cole 08 Feb '10

08 Feb '10

I copied two stations on SSB at 435.733 for the second half of pass #732, 10:30-10:50 utc. They did not pass call signs while I listened. I hadn't reprogrammed he FT-847 for SSB so my uplink was on the wrong freq. but Rx signals were "arm-chair" until elevation < 10 deg. Not too bad for omni-directional antennas. I looked up the freq. info after the pass and discovered why I didn't hear my self (uplinking at 145.825). I now have a separate satellite memory setup for the SSB freq. of HO68 (435.740Rx/145.950Tx). The next pass is for 0020-0105, Feb. 9. My window will be 0052-0109utc when HO-38 is mainly over arctic Canada and no footprint for lower-48. It is a ascending pass so I will have about ten min of coverage (0055-0105). Look for me on SSB. 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com 500-KHz/CW, 144-MHz EME, 1296-MHz EME DUBUS Magazine USA Rep dubususa(a)hotmail.com ======================================

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FS: TAPR EVM
by Bob DeVarney W1ICW 08 Feb '10

08 Feb '10

For sale, TAPR EVM DSP-based modem, complete and assembled, with all documentation and cables, plus a cdrom with all pertinent software. In excellent condition, was in regular use until my interests changed. Asking $300.00 plus shipping and insurance. Please contact me off-list if interested. 73, Bob W1ICW we1u(a)nospam.myfairpoint.net ( remove the nospam )

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Looking for 440 preamp
by Sebastian 08 Feb '10

08 Feb '10

I'm looking for a used but good 440 preamp, one that can handle at least 50 watts or so. Please reply off list with make, model, etc. 73 de W4AS

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Re: HO-68 Schedule - 07-21 Feb 2010
by Henk, PA3GUO 08 Feb '10

08 Feb '10

Thanks Alan ! Will again be a lot of fun and experimenting ! Henk, PA3GUO http://www.youtube.com/watch?v=o6oDgUTHCwg

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Shuttle Launch
by Clint Bradford 08 Feb '10

08 Feb '10

In case you missed it, here's a link to a HD video of this morning's launch of the Endeavour. http://tinyurl.com/y8uhdhj The Endeavour is carrying a lot to the ISS, including the last module - Tranquility - the 21-foot-long, 14-foot-wide module that will be mounted to Unity, facing Earth. Tranquility includes an attachment called Cupola - a huge viewing port with seven windows (six on the sides, and one on top). Clint, K6LCS

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FO-29 Telemetry 08-02-2010 19:00 CEST
by PE0SAT 08 Feb '10

08 Feb '10

Here FO-29 Telemtry I received 08-02-2010 19:00 CEST HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 7A 65 9C 9C F0 8C 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 4D 65 9C 9C F0 42 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 3C 66 9C 9C ED 7A 8D 86 83 89 86 HI HI 20 CT 88 D5 00 84 00 00 09 60 01 01 30 6A 98 97 E0 8B 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 32 68 95 94 E2 78 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 43 62 97 96 F0 79 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 75 64 99 99 F1 88 8D 86 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 7C 65 9A 9B F1 77 8D 87 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 7A 65 9B 9B F1 78 8D 87 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 78 65 9C 9C F0 73 8E 87 83 89 86 HI HI 20 C2 88 D5 00 84 00 00 09 60 01 01 76 65 9C 9C F0 7B 8E 87 83 89 86 73 Jan PE0SAT

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Re: LVB Tracker and Kenpro
by n4hy 08 Feb '10

08 Feb '10

Flex is fully aware that the price of the V/U + the 5000 will limit the sales of the V/U. For those already owning the 5000, the V/U together as two sixty watt units with high performance and fully capable of full duplex operation, and is CHEAPER than the same system assembled from DEMI units. Now, you have to already have the 5000 to plug it in so it is limited to the 5000. The Flex equipment is fully capable of supporting external digital programs and CAT. Both of these are supported via "virtual connections". A pseudo sound card is set up and other programs connect to the pseudo sound card to deliver audio to/from the radio. The same thing for CAT control: a pseudo com port pair is set up, one at the radio and one at the controlling program, to support control of the radio via CAT commands. The radio has its own set of commands but implements Kenwood commands as well. I have the USB version of the LVB tracker and the latest model Kenpro (5400A) with the relay control lines brought out to the plug. The LVB plugs into that plug directly. This is good. I should have remembered this because Brooks developed the KCT Tracker and Tuner with the interface to Quiktrak at the beginning of our friendship. I used both to command the Microsat's in the first days, I should have remembered and should have realized that the plugin interface probably became a standard when Kenpro did and Yaesu maintained it in the B model. Thanks Mark! Bob On 2/7/2010 8:33 AM, Mark L. Hammond wrote: > Hi Bob, > > > Really, at the risk of oversimplifying, "all" the LVB tracker does is ground pins, so any rotor hardware/interface that works from that principle is set. > > I'm sure lots of us are interested in real world performance and ease of use reports from the Flex with VHF/UHF. I just wish the blooming thing didn't approach $4-5k. > > Are there any software solutions (or plans) for satellite packet at various speeds, such that a KISS virtual com port is available at different rates? Otherwise, how does one get the data out of the "magic black box?" > > 73, > > At 10:48 PM 2/6/2010 -0500, n4hy wrote: > >> Thanks to all who answered my (incomplete) email. >> >> It is clear to me now that my Kenpro 5400-A, which has an external >> control on the back, can be made to work with the LVB tracker. >> >> After the 2 feet of snow melts, I will be refurbishing the rotator where >> needed. I am hoping this and the antenna deployment coincides with the >> arrival of my U/V full duplex 60w on both bands, transverter block >> arrives from Flex and I get back on satellites again. >> >> 73's to all and thanks again for the answers. >> Bob >> N4HY >> >> -- (Co)Author: DttSP, Quiktrak, PowerSDR, GnuRadio Member: ARRL, AMSAT, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. “Our beds are empty two-thirds of the time. Our living rooms are empty seven-eighths of the time. Our office buildings are empty one-half of the time. It’s time we gave this some thought.” -- R. Buckminster Fuller Active: Facebook,Twitter,LinkedIn

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Office Closed
by Martha 08 Feb '10

08 Feb '10

Due to the Blizzard of 2010, the AMSAT office is closed. I will be in (hopefully) tomorrow. -- 73- Martha

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Endeavour 36394
by JC-Aveni 08 Feb '10

08 Feb '10

Spacetrack Endeavour = NORAD ID 36394 2010-004A 73 Jean-Claude tk5gh

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