January 2014 - AMSAT-BB - mailman.amsat.org

Re: 145 MHz signal blocking 435 MHz downlink
by kc6uqh＠cox.net 26 Jan '14

26 Jan '14

Greg, I had a problem with 70cm jamming 2401 down link many years ago. The problem turned out to be corrosion between the coax connector shell and the aluminum antenna element. Cleaning up the connection solved the problem. The corrosion acts like a diode and will make enough 3 order products to trash any receiver. Use liquid electrical tape or non-corrosive (doesn't smell like vinegar) silicon seal to keep these connections dry and clean. Art, KC6UQH -----Original Message----- From: amsat-bb-bounces(a)amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of g0mrf(a)aol.com Sent: Monday, January 20, 2014 1:23 AM To: ko6th.greg(a)gmail.com; kq6ea(a)verizon.net; w4tas(a)gte.net; amsat-bb(a)amsat.org Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink Hi Greg. Most decent VHF transmitters will already have a pretty good LPF on the output to reduce the harmonics. However, receivers these days tend to be DC-Daylight, so frequently need a filter to prevent 'blocking' by unwanted high level signals. In that case preventing the VHF coming into the UHF receiver can be important Thanks David -----Original Message----- From: Greg D <ko6th.greg(a)gmail.com> To: Jim Jerzycke <kq6ea(a)verizon.net>; w4tas <w4tas(a)gte.net>; 'AMSAT Mailing List' <amsat-bb(a)amsat.org> Sent: Mon, 20 Jan 2014 3:47 Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink I know this has been answered before, but I forget. Given one Diplexer, is it better to put it on the Tx side to limit the 3rd harmionic going out, or better on the Rx side to limit the VHF fundamental coming in? Tony's diagram shows the later; I would have thought the former would be more effective (hitting the problem at its source). Greg KO6TH Jim Jerzycke wrote: > Yep, been using one of those for years! > > I have a Sinclair Labs unit that provides 100dB rejection outside of > the 2 Meter band. > > Jim KQ6EA > > > On 01/19/2014 07:32 PM, w4tas wrote: >> I would also suggest a low pass filter on the two meter transmitter. >> A diplexer will work well for this also. >> This will reduce the third harmonic which is causing your problem. >> >> Good luck, >> >> >> >> >> -----Original Message----- From: Jim Jerzycke >> Sent: Sunday, January 19, 2014 2:09 PM >> To: amsat-bb(a)amsat.org >> Subject: [amsat-bb] Re: 145 MHz signal blocking 435 MHz downlink >> >> Buy a diplexer, and connect it as shown in the linked article: >> >> >> http://www.amsat.org/amsat-new/articles/Mode-J/ >> >> I also tilt both of my Yagis so they're 45* to the boom, which makes >> them 90* to each other. >> >> Yes, I lose some signal on terrestrial use, but ti helped cut the >> coupling, and desense, down quite a bit. >> >> 73, Jim KQ6EA >> >> On 01/19/2014 06:56 PM, Gabriel - EA6VQ wrote: >>> Hi all, >>> >>> I have a coupling problem in my station when trying to work FO-29. >>> My 2m >>> signal is completely blocking the 435 MHz downlink, and so I can't >>> hear my signal off the satellite. I guess it must be something >>> related to the distance between the two yagis. (I use the >>> terrestrial horizontal yagis you can see at >>> http://www.dxmaps.com/jm19hn.html ). With mode-B satellites there is >>> no problem. I have tried it with two different 435 receivers, and >>> it's exactly the same. >>> >>> Anyone has had this problem o have an idea of the possible reason? >>> And what >>> is more important, of some way to solve it? >>> >>> Thanks for any possible help. >>> >>> 73. Gabriel - EA6VQ >>> _________________________________________________________ >>> Web-Site: HTTP://www.dxmaps.com >>> VQLog 3.1 (build 78): HTTP://www.vqlog.com >>> _________________________________________________________ >>> >>> >>> _______________________________________________ >>> 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 >>> >> >> _______________________________________________ >> 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 >> > > _______________________________________________ > 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 _______________________________________________ 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 _______________________________________________ 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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Re: FunCube observations
by Clint Bradford 26 Jan '14

26 Jan '14

>> ... Most everyone knows about Funcube and how successful it has been. YES - AMSAT-UK knows the value of publicity, marketing, and planning. Their use of several social media programs is fantastic. They KNOW how to throw a "party." Clint Bradford K6LCS

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A quick follow up comment to the " Status" discussion
by Michael 26 Jan '14

26 Jan '14

BTW, What always attracted me to sat operation in the first place was not how "simple" it was but how "complex" it was. I originally took it on because of the challenge involved. A lot of people become bored with things when they become too easy. I think we sometimes do ourselves a disservice with the HT and handheld antenna demos showing everyone how "easy" it is. For example, I had someday hoped to try EME but even that is losing some of it's appeal to me now because it's not as hard as it used to be. Again, just my humble opinion.... 73, Michael, W4HIJ

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status
by John Becker 26 Jan '14

26 Jan '14

Whats the status of a replacement for the likes of AO 40? I know I ask this from time to time but never seem to see anything. I for one would very much like to see this type the a boat load of small FM only type while there is still a place to park one. John, W0JAB

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2014 UK CubeSat Workshop
by M5AKA 26 Jan '14

26 Jan '14

The UK CubeSat Workshop, planned for Tuesday, May 13, 2014, will include presentations on the amateur radio satellites FUNcube-1 and UKube-1, see http://amsat-uk.org/2014/01/26/2014-uk-cubesat-workshop/ ---- 73 Trevor M5AKA AMSAT-UK website http://amsat-uk.org/ Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396 Twitter https://twitter.com/AMSAT_UK ----

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G5400B calibration problems
by Tim Goodrich 26 Jan '14

26 Jan '14

Hello All, I could use some help with the alignment/calibrating of my az/el rotor to my rotor controller. I followed the G5400B manual instructions and set the rotor and antennas to the full south position. The meter indicated full stop at the south position as well. I then depressed the azimuth control to bring the rotor around 360 degrees back to south. The first 5-10 seconds, the antennas moved and the meter needle was not moving. However, when the rotation was complete, although the antennas were pointed south, the meter stopped just a couple degrees away from south, so I used the rear pot adjustment to zero it. I then swung the other way attempting to go back to my starting position. After the meter hit full stop at south in the original position, I looked at the antennas and they were about 45 degrees short of full south. According to the manual, I followed the steps correctly, but no matter what I do, I cannot get the meter to always accurately reflect where the antennas are actually pointing. Can anyone tell me what might be wrong? Thank you, Tim K6TW

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LOL
by Kevin Deane 25 Jan '14

25 Jan '14

HA HA Kevin KF7MYK

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OF40R
by Wyatt Dirks 25 Jan '14

25 Jan '14

Good afternoon Just got off a 4 degree ao7 pass and worked OF40R a special event over in Finland. According to QRZ the event is going to be going on for quite some time yet. Tomi(OH4MS) who was the operator had a very good signal into ao7 and seemed to hear just fine. Most of the time the hearing is the hard part. Grid reported was KP24. He was looking for more calls but only a few takers. 73 Wyatt AC0RA

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Re: AO-73 question
by Todd Bloomingdale 25 Jan '14

25 Jan '14

Ok. Yes Sorry was typing my phone. Yes I was talking about SSB. I have an HF all mode, but don't have 2 meter or 70 cm on that radio. I have a couple FM baofengs HT's. So guess I use them for SO-50. Ive been doing some reading and thinking of getting a USB dongle. Ive been reading on the funcube dongles, but not in my budget right not, but was looking at these cheap dongles. Will they work for AO-73 and other satellites? Todd Bloomingdale- KC9LOX Tomah, WI On Mon, Jan 20, 2014 at 2:38 PM, Patrick STODDARD <patrick(a)wd9ewk.net>wrote: > Todd, > > If you were meaning to type SSB for the type of signals > transmitted from AO-73, then yes - you will need a radio > capable of SSB reception to copy anything from AO-73 - > telemetry or transponder. If you have access to a > Kenwood TH-F6A HT, this radio has an all-mode receiver > which may be sufficient for copying the telemetry and > the transponder from AO-73. For the telemetry, you would > patch the speaker audio from the radio into the mic jack > on a PC running the FUNcube Dashboard software from the > www.funcube.org.uk web site, and set the radio around > 145.935 MHz USB (probably start closer to 145.938 MHz > at the start of a pass, and end up around 145.932 MHz > near the end of the pass). Make sure the radio you use > has small tuning steps, and be ready to tune down during > the pass. > > The daytime passes are the easiest to copy telemetry, as > the transponder is off at that time. The telemetry is still > on at night, but at 1/10 the power level that is used for > the daytime passes (30mW downlink at night, compared to 300mW > in daylight) to allow for the transponder to operate. The > transponder transmits at 300mW across its 20 kHz passband, > betwen 145.950 and 145.970 MHz - use USB for best performance > when listening to the transponder. You can see some slideshow > videos of me working the AO-73 transponder, using different > radios as the receiver, on my YouTube channel: > > http://www.youtube.com/va7ewk > > Hope that helps. 73! > > > > > > Patrick WD9EWK/VA7EWK > http://www.wd9ewk.net/ > > > > > > On Mon, Jan 20, 2014 at 1:11 PM, Todd Bloomingdale < > tbloomingdale(a)gmail.com> wrote: > >> I'm interested in trying to receive the AO-73 telemetry. Currently, I'm >> not >> able to SB, so I know that the transponder is out of question for me. But >> is a SB radio needed for the telemetry? >> >> Todd Bloomingdale- KC9LOX >> Tomah, WI >> _______________________________________________ >> 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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Re: K4AMG on AO-73 today
by Andrew Glasbrenner 25 Jan '14

25 Jan '14

AO-73 is telemetry only during illuminated passes. The transponder is only on when the satellite is eclipsed,at night. 73, Drew KO4MA -----Original Message----- >From: Rich/wa4bue <richard.siff(a)verizon.net> >Sent: Jan 25, 2014 8:40 AM >To: amsat-bb(a)amsat.org >Subject: [amsat-bb] K4AMG on AO-73 today > >If it is a favorable pass K4AMG will be on AO73 this morning at 1420 UTC > >So far only 1 QSO KB3M. Maybe one of you will be on. I will be about >center about .960 freq SSB > >This will complete our test of new antenna system on all linear trasnponder >birds and SO 50. > >God Bless > >Rich W4BUE >K4AMG club > >_______________________________________________ >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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