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{
    "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/F4QFRWX5BOJRMWJFYKXP7JG3AKM5M52M/?format=api",
    "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/?format=api",
    "message_id": "CANq+eyWZFaJex+-22KLPXOVORBCP=fNL1CEnwHOr4L7xWuqpaw@mail.gmail.com",
    "message_id_hash": "F4QFRWX5BOJRMWJFYKXP7JG3AKM5M52M",
    "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/S7WU3SRI65LBIOBWGV6ASH7U4WTJ4QAJ/?format=api",
    "sender": {
        "address": "dave (a) druidnetworks.com",
        "mailman_id": "3b01b396750a47f287ea0c65babd40ea",
        "emails": "https://mailman.amsat.org/hyperkitty/api/sender/3b01b396750a47f287ea0c65babd40ea/emails/?format=api"
    },
    "sender_name": "David Swanson",
    "subject": "Re: [amsat-bb] WSJT-X FT8 QSO confirmed between W2JAZ and W5RKN on\tFO-29",
    "date": "2017-10-17T04:03:06Z",
    "parent": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/S7WU3SRI65LBIOBWGV6ASH7U4WTJ4QAJ/?format=api",
    "children": [
        "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/DGY7XPVKUVOBH2WXI4HLOQ32ACFSYHW6/?format=api"
    ],
    "votes": {
        "likes": 0,
        "dislikes": 0,
        "status": "neutral"
    },
    "content": "On the FO29 pass at 0155z this evening, I noticed a very hard time getting\ninto the transponder. The pass was nearly overhead, and the 3w-4w that is\nnormally sufficient was barely cutting it. I also noticed it was 'up and\ndown' alot, whereas some moments it was easy to get in, then it would be\nnearly impossible. There were also pockets of 'noise' all over the\ntransponder, that sounded somewhat digital, but I just couldn't place them.\nI found W5PFG in the passband (who was portable in a rare grid in western\nTexas) and he commented on the difficulty of working an otherwise easier\nbird tonight as well. I checked the screen, and no other birds were\nobviously in range, so I started scanning around the passband to see what I\ncould hear. Up around 435.870 I found (or rather heard) what I was looking\nfor. I fired up my recorder and captured this:\n\nhttps://drive.google.com/open?id=0B8W_KstbAsD_VF9NbGR3ZXlicUE\n\nFor those not familiar, that is the telltale sound of MSK144. I work a fair\namount of Meteor Scatter in addition to operating satellites, and the noise\nis unmistakable. Since my shack PC has wsjt-x installed, I quickly fired it\nup and went to the msk144 mode and after some quick tweaking started\ndecoding the signal. This is a screenshot of what I saw:\n\nhttp://druidnetworks.com/w5rkn-msk144-fo29.jpg\n\nThis signal continued for at least 8 minutes (that I recorded) in a 5\nsecond T/R cycle while FO29 was passing high over North America. Every 5\nsecond the digital signal would get transmitted, and all other SSB qsos\nwould start to fail. You might call this an experiment, but I call it\nintentional QRM.\n\n*For the record* You are not the first person to play with wsjt-x modes on\nthe linear satellites. Some months ago during the late night hours on the\nXW's and FO29 when the footprint was primarily over the desert southwest\nand south pacific, I to \"experimented\" with FT8 and MSK144. I purposely ran\nmy transmitted signal thru over 100ft of low grade coax to attenuate my\nuplink to ~1.5w ERP. I made sure the entire transponder was empty before\nstarting, announcing myself, then started the transmission. I decoded\nmyself successfully, said \"Well that was dumb\" and never did it again. I\npurposely didn't announce what I had done to the world because I knew\nsomeone would think they were being cool too, and would fire up a 2700hz\nwide 50% duty cycle mode on a high US pass and QRM people trying to make\nQSOs out of existence, because said individual would lack even basic\nsituational awareness and courtesy to others. What is extra hilarious about\nthe fact that it is you being the responsible party for destroying a pass,\nis your constant whining to this mailing list about people using too much\npower on AO-7, when you're one of the worst offenders. On July 16th this\nsummer, I was roving in EM35 and you called me on the 2155z pass of AO7,\nand you got the first 3 letters of your callsign out before you killed the\nbird. I know it was you, because I had already made 3 QSOs right at my AOS\nwith other stations using a reasonable amount of power, and as soon as you\nkey'd up the whole bird started FMing and croaked before you even finished\nyour call. You didn't get that grid that day, and after the stunt you\npulled this evening - you won't be getting any grids from me in the future\neither.\n\n-Dave, KG5CCI\n\n\n\n\n\nOn Sat, Oct 14, 2017 at 2:24 PM, Ronald G. Parsons <[email protected]> wrote:\n\n> Dave,\n>\n> I some sense you are right, but this is a weak signal mode usable only\n> when the satellite is far away so the Doppler shift change each second is\n> very small.  It isn’t the power being transmitted, but the power received\n> at the satellite that matters, and it was being used only when the\n> satellite was near maximum range. There were other signals on the\n> transponder, both SSB and CW, that were so strong they were causing both\n> amplitude changes and “FMing” of my downlink signal. During preliminary\n> testing with the satellite near, I observed no noticeable changes to other\n> signals in the passband when my signal was strong. Strong CW and SSB\n> signals from others, due to their amplitude changes did produce noticeable\n> changes to my downlink. This could be why we were not successful on AO-7,\n> but were successful on our first try on FO-29, which is more tolerant of\n> other strong signals on the passband.\n>\n> Ron W5RKN\n>\n> On Oct 14 14:34:56 UTC 2017, \"Dave Webb KB1PVH\" <kb1pvh at gmail.com>\n> wrote:\n>\n> >Ron,\n> >\n> > I feel your email is a little like \"Do as I say, not as I do\". Aren't you\n> >posting repeatedly asking people to use low power on AO-7, and here you\n> are\n> >attempting a full duty cycle mode on AO-7.\n> >\n> >Dave-KB1PVH\n> >\n> >\n> >Sent from my Galaxy S7\n>\n> On Oct 13, 2017 11:18 PM, \"Ronald G. Parsons\" <w5rkn at w5rkn.com> wrote:\n>\n> > A few days ago, Rick, W2JAZ, asked me if the new, short, weak signal\n> > protocol, FT8, could be used on satellites. I posited it might work near\n> > AOS or LOS where the Doppler corrections are small. FT8 is operationally\n> > similar to the older protocols but four times faster (15-second T/R\n> > sequences) and less sensitive by a few dB.\n> >\n> > So we set out to configure our satellite stations to use WSJT-X with FT8.\n> > With some configuration advice from W0DHB, we each got our systems\n> > configured. Mine (W5RKN) is a Flex-6500 with two DEMI transverters\n> running\n> > SmartSDR, SatPC32, FlexSATPC, and WSJT-X. Rick’s (W2JAZ) is a Flex-5000\n> > with U/V module, running PowerSDR, SatPC32, FlexSATPC, and WSJT-X.\n> >\n> > After a couple runs on AO-7 without success, we tried again tonight on\n> the\n> > 0220Z (14 Oct) pass of FO-29. I started out at my AOS calling CQ W5RKN\n> > EM10. After several transmissions without success, the reply W5RKN W2JAZ\n> > FN29 popped up on the screen. Then followed the usual signal report, RRR\n> > and 73 transmissions.\n> >\n> > As soon as I can figure out the appropriate fields for LoTW, we’ll log\n> the\n> > QSO there.\n> >\n> > I am not aware of other WSJT-X QSOs on the satellites, so I’d be\n> > interested in other’s experiences,\n> >\n> > Ron and Rick\n> _______________________________________________\n> Sent via [email protected]. AMSAT-NA makes this open forum available\n> to all interested persons worldwide without requiring membership. Opinions\n> expressed\n> are solely those of the author, and do not reflect the official views of\n> AMSAT-NA.\n> Not an AMSAT-NA member? Join now to support the amateur satellite program!\n> Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb\n>\n",
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