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Re: [amsat-bb] Satellites with 2.4 GHz
by MICHAEL WILLIAMS 23 May '20

23 May '20

DTUSat-2 at 2401.835 MHz. Object 40030. Sends out CW beacon every 30 seconds. No battery power so operates only in sunlight. Daylight passes are normally from 11:00 to 13:00 every day. Beacon can be a missing, intermittent, full or partial CW message. It has a good signal on 2.4 GHz. As Doppler is extreme, it's best viewed on a SDR waterfall. A picture of DTUSat-2's waterfall signal is on my QRZ page. It's a good signal to test your 2.4 GHz setup and tracking. Most satellites on 2.4 GHz only turn on and down link their data when over the command station. You must be in command station's foot print to hear the signal. GL

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AO-92 interference.
by Tom Schuessler 22 May '20

22 May '20

Yes there are hundreds and thousands of 70 cm repeaters that are coordinated in the northeast US. They are all supposed to be in the proper FM voice range of 440 through 448. The issue here is with what is probably an uncoordinated private repeater with an input, but most likely an output wrongly put in the satellites sub-band on 70 cm. It is well within our rights to attempt to locate the source of this interference and in proper amateur radio style, attempt to convince the owner to move. That is what the volunteer monitoring program run by ARRL is all about, to find interference and help eliminate it. So it doesn’t have to go to the FCC. Their operation is not illegal but it is out of band plan. AMSAT volunteers should reach out to the coordinating groups in all of the north eastern states and bring the situation to their attention. There should also be contact made to the ARRL MONITORING group to make them aware of the problem as well. The more ears listening on these frequencies, the more chance it will be found by somebody on the ground. Tom N5HYP

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Re: [amsat-bb] PSK retransmission on PSAT-2 (now SSTV?)
by Robert Bruninga 22 May '20

22 May '20

Using translate.google.com it appears that Roland captured his PSK31 two-way PSK31 via the HF to UHF transponder (just what PSAT2 is designed to do via the Brno transponder).. What I'd like to see is another station transmitting SSTV at the same time to see if we can do a 2-way SSTV via the transponder. My previous emails on the topic were hampered by the need to make sure there was a PSK31 carrier also in the passband at the same time. Which is hard to do from one PC and existing software.. BUT!!! The easiest way is for two stations to make a SKED and one transmit PSK31 and the other transmit SSTV at the same time. That will keep the transponder up. Then they SWAP after the first successfully SSTV relay and the other person sends the PSK31 while receiving the SSTV. Since PSAT2 is full duplex HF up and UHF down, both stations can TX and RX at the same time and it is easy! No special hardware or software required! A sked would go like this. The first person simply brings up PSK31 software and sends CQ SSTV, CQ SSTV continuously asking for an SSTV contact. Another station, hearing the transponder come up, then Transmits his SSTV image on the same 10m uplink and both stations can see and hear in real time both signals. When the SSTV receiving station (who is TXing the CQ SSTV message) gets an image, then he changes his MSG to QSL and then he waits for the other station to drop his SSTV tones and come up on PSK31. This will now hold up the transponder for the original station to now drop his PSK31 and switch to transmit his SSTV! With 40 seconds per image, this will need a good 1.5 minute mutual pass... for a 2-way SSTV exchange Bob, WB4APR -----Original Message----- From: AMSAT-BB <amsat-bb-bounces(a)amsat.org> On Behalf Of Roland Zurmely via AMSAT-BB Sent: Thursday, May 21, 2020 1:45 PM To: AMSAT <amsat-bb(a)amsat.org> Subject: [amsat-bb] PSK retransmission on PSAT-2 < https://www.qsl.net/py4zbz/psat2.htm#b > 73 de Roland PY4ZBZ

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Re: [amsat-bb] Terrible Repeater QRM on AO-92 at 15:40z
by Roy Dean 22 May '20

22 May '20

> > Yes, terrible QRM during this pass. Have recording as well but no call > signs from repeater chatter. Cal / N3CAL https://youtu.be/4439iHT4vtM --Roy K3RLD

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Satellites with 2.4GHZ
by Pete vk2pet 22 May '20

22 May '20

Good morning everyone, Does anyone know of known good satellites with either telemetry or beacon between 2.400GHZ & 2450GHZ? Been looking on Satnogs without luck yet. 73's Pete VK2PET

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Re: [amsat-bb] Huskysat in "incognito" mode
by Roy Dean 21 May '20

21 May '20

Any dirt on Huskysat-1? Not heard from in over a day. :( --Roy K3RLD

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Terrible Repeater QRM on AO-92 at 15:40z
by Stephen DeVience 21 May '20

21 May '20

I wouldn't mix this together with purposeful QRM, which is a separate problem. >From previous recordings, we think it's the W1GLO repeater causing the trouble ( or someone crossbanding it). It is on echolink and has a live stream: http://caara.net/main/repeaterstream/ Maybe somone can set something up to record the repeater during satellite passes so we can prove or disprove it. This would be a good youtube link to send the W1GLO club as well. -Stephen, N8URE

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Re: [amsat-bb] Terrible Repeater QRM on AO-92
by Brad Smith 21 May '20

21 May '20

<I look at it this way. If all the idiots want to jam the crap out of theFM birds, so be it. That means they are leaving the linear birds alone.> I have been studying the QRM patterns. 92 seems to have the most, but also on Western passes, which would rule out a New England repeater. 91 has it's share. I believe it is done by a few jammers, who have set out to disrupt. Malcontents about something, but with enough power to take the sat. repeater away from someone who is talking. Today, on 92, one person was targeted. Every time she tried to give her call to complete a contact the "open mic" began and blocked her transmission. I finally came after her and gave her call. That must have worked. But its not just the open mic. Its the feedback squeal that can knock your earphones off and it continues for a while. That's intentional. I am hoping that in a couple of years, when the SSB bands get better, the malcontents will go back to SSB. I also believe the whistlers just have a poor setup and are trying to find themselves on the bird. Tonight, there was a whistler on SO-50! Brad KC9UQR

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FS Icom AG-35
by Howard Stephenson 21 May '20

21 May '20

Looking to sell my Icom AG-35 430 MHz preamp $65 shipped in the lower 48 73 Howard Stephenson K6IA Las Vegas

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Terrible Repeater QRM on AO-92 at 15:40z
by Roy Dean 21 May '20

21 May '20

> > Hi Roy What happens when the world ends? You and I and just about everyone > is not > able to control the future. If we all thought about 'what if' we wouldn't > have gotten out of the stone > age and the Wright Brothers wouldn't have flown. All we can do is deal > with the present and the facts we have at hand. I look at it this way. If > all the idiots want to jam the crap out of the > FM birds, so be it. That means they are leaving the linear birds alone. > Mike va3mw Mike, perhaps my use of the term "QRM" is incorrect, or perhaps you didn't listen to the recording? This is not one or more "a-hole" operators intentionally trying to interfere with satellite operators. This is the output of a New England (we think, based on operator accents and 1 area callsigns) repeater that is either on the AO-92 uplink, or has a very strong harmonic accomplishing the same thing. From what I've read, the AMSAT team is working with at least one repeater on a solution, and they have continued to ask for recordings. And again, I stress that somebody putting a repeater output in the same uplink frequency band as any of the linears will cause the EXACT same problem, if not even worse. So we should either nip this in the bud, or face giving up the satellite sub-bands entirely. As far as your "what if" comment, people like the Wright Brothers DID, in fact, think "what if". In less than a week we will have the first purpose designed commercial space flight service.... --Roy K3RLD

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