December 2017 - AMSAT-BB - mailman.amsat.org

Re: [amsat-bb] A suggestion for Experimenter's Wednesdays on AO-91
by radiomb 15 Dec '17

15 Dec '17

I have only made a few contacts on the FM birds, so a very newbie. Ramping up quickly with my Christmas wish list for linear birds. If SSTV has run its course, please do not stop all together. Maybe can rotate different weeks of the month for experimental day. I have only heard one SSTV picture on the bird a few weeks back but remember it well. Still remember my 1st HF SSTV contact Ivory Coast. I think keeping SSTV some weeks may get a few more people interested in satellites, just like ISS SSTV. Sure wish the US would send as many ISS pictures as the Russians. I do not understand that either. 73 Mike K4MIA

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A suggestion for Experimenter's Wednesdays on AO-91
by Patrick STODDARD (WD9EWK/VA7EWK) 15 Dec '17

15 Dec '17

Hi! Now that AO-91 has been going strong for about 3 weeks, maybe it is time to come up with something for it on Experimenter's Wednesdays, like we have seen with SSTV on AO-85. Although I think the SSTV has run its course and maybe something else should be tried, I'm not suggesting any particular change to AO-85 on Wednesdays. This is only intended as a suggestion for AO-91. After Sean KX9X published his recent document with a list of good operating practices for FM satellites: https://www.amsat.org/fm-satellites-good-operating-practices-for-beginning-… my suggestion would be a way to encourage this, especially focusing on one item. I tweeted a little earlier this afternoon the following: "An AO-91 Experimenter's Wednesday suggestion: 5W or less, ideally using HTs or portable setups & handheld directional antennas or whips/duckies. Let's take full advantage of how well this satellite hears & can be heard on the ground." One comment I received on Twitter questioned having something for Experimenter's Wednesdays on both AO-85 and AO-91, suggesting that another day of the week should be used for AO-91. I disagreed with that, given that it is "Experimenter's Wednesday". Unlike with AO-85 where the focus has been SSTV, my suggestion would still allow for FM voice QSOs on AO-91 - but with a focus on using less power and smaller stations. This would also go directly to the recommendations that were recently published. For those who may be concerned about doing something like this on 2 of the 3 FM satellites, there has been Experimenter's Wednesday SSTV activity for a while now. Most of the time, this has been done when we only had two working FM satellites (AO-85, SO-50). Maybe we could see some coast-to-coast QSOs on AO-91 where both stations are using power levels at 50mW or 100mW, for example. Thanks, and 73! Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK or http://twitter.com/WD9EWK

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Re: [amsat-bb] A suggestion for ... Emergency Comms - 1200 bd 10m uplink.
by Robert Bruninga 15 Dec '17

15 Dec '17

Actually, why wait till Experimental Wednesdays. 1200 baud AX.25 packet is legal uplink for PSAT's 28.120 USB uplink and 435.350 downlink (unless I misread the rules). SO I will say that such experiments are welcome on PSAT as long as there is little to no other PSK31 activity in the 1000 to 2400 Hz tones on the air at the time of the experiment. Doppler during a 1 second packet burst will be insignificant.... OOPS, insignificant, but critical. One has to pre-shift your uplink so that your downlink does come down at the standard 1200 baud AFSK tones of 1200,2200 Hz. I guess the key there is to transmit your PSK31 "pilot" signal for a few seconds at say 500 Hz on the uplink, adjust your uplink Transmitter RF to verify you see it at 500 Hz in the downlink and then transmit the packet. I'd love to see this transponder used more. But again, the uplink is shared with terrestrial PSK31, so share the band. You can verify a clear band by looking (or listening) in the downlink if there are ANY PSK31 users in the 1000 to 2400 Hz bandwidth prior to transmitting. Bob, WB4APR -----Original Message----- From: Robert Bruninga [mailto:[email protected]] Sent: Friday, December 15, 2017 10:03 AM To: amsat-bb(a)amsat.org Cc: Robert Bruninga Subject: A suggestion for ... Emergency Comms - APRS... Such a highly compressed method of satellite encoding exists called APRS. >> ... the limiting factor for using LEO satellites as an Emergency >> Response of any scale, would the short amount of time of a given pass >> and the limited number of usable passes a day... > But, us ingenious ham radio operator types perhaps have the basis of > sending compressed data which conveys a lot of information. > Packed into the bytes of telemetry messages ... > How about a predefined disaster status data stream that all shelters... Use the APRS Object for a SHELTER. Just one packet can contain the position, time and date of the report, and up to 47 bytes of useful info such as 1) head count of staff 2) head count of victims 3) electrical power 4)drinking water 5) more supplies needed 6) need critical assistance. > Conversely, if multiple LEO satellites support a disaster-status protocol.. They do. APRS is currently on 3 sateliltes... PSAT, ISS and PCSAT and soon to be QIKCOM2 and PSAT2 and BRICSAT2... And TJHS hicghschool cubesat, etc > We'd need future cubesat missions capable of supporting a disaster telemetry stream. We have it. See the SATT4 single card APRS transponder. We invite every school or university that is contemplating a CUBESAT to consider using this transponder for their command and control which also provides the APRS transponder as well. Cost is under $300 or so. See http://aprs.org/satt4.html Bob, WB4aPR

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AO73/FUNcube-1 Mode
by Graham Shirville 15 Dec '17

15 Dec '17

Hi All, Just to confirm that AO73/FUNcube-1 is now in continuous transponder mode for the weekend as usual. Have FUN 73 Graham G3VZV

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Odd TH-D74 behavior
by Brent Taylor 15 Dec '17

15 Dec '17

Hi everyone, Yesterday (Thursday), while on my whirlwind FN87/77 grid activation trip, I ran into a frustrating thing with my TH-D74. Wanting to use (Bose QC15) noise cancelling headphones for my downlink audio, I used a 2.5mm male to 3.5mm female adapter pigtail to take the "SP" audio off the side of the radio and feed it into the headphones, while using my VX-8GR for full duplex transmit (for AO-91). The problem: every time I plugged the pigtail into the side of the D74, its frequency would change and the ability to QSY back to the intended downlink frequency would be severely limited or even prevented altogether. I wanted to be in VFO mode, for instance, and plugging the pigtail into the speaker jack immediately took me to memory channel recall mode, on an apparently random channel, and then prevent the selection of another memory or a return to VFO mode. So I thought I'd fix that problem by locking the radio with the long press on the "F" key. No change in behaviour. The frequency change still happened every time I plugged in to the speaker jack. The problem sometimes occurred immediately upon plugging in, but sometimes it would work fine on VFO mode for a few seconds before the changeover. I will continue to fiddle with it to set put exact behaviors in varying circumstances. I'm just wondering if anyone else has experienced a similar problem. What I ended up doing was going without headphones altogether and just listening to the D74 out of its own speaker, in the wind, with feedback on the uplink when I transmitted. Sorry about that mess! 73 Brent -- Brent Taylor, VY2HF / W1PJ Stratford, PEI, Canada

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WD9EWK from DM23/DM24 line tomorrow (& maybe a little more...)
by Patrick STODDARD (WD9EWK/VA7EWK) 15 Dec '17

15 Dec '17

Hi! Tomorrow (Saturday, 16 December) morning, I will head out to western Arizona and operate on the DM23vx/DM24va grid boundary. This spot is north of the AZ-72/AZ-95 junction, north of Quartzsite and southeast of Parker. I plan on being here from mid-morning into the afternoon, working FM, SSB, and - if available - packet passes. Sometime in the mid- to late-afternoon, I am probably going to drive north to Kingman and the DM25/DM35 grid boundary for some passes up there. Ideally, I might be able to get in on some of the XW-2 "train" for the east coast, but would stay there for a couple of hours before returning home. If there is snow in or around Kingman, I will not head this way, and may look at an alternative loop for the drive home (i.e., returning via Yuma AZ and the DM22/DM32 boundary near I-8). For the night owls, I might still be up for at least one AO-91 pass late Saturday evening. For that pass, I might be home at that point, but I will make note of the AO-91 pass times to make sure I don't forget them. While on the road, I'll run APRS from my car as WD9EWK-9. There should be decent coverage for most of my planned road trip on sites like (among a few others) http://aprs.fi/WD9EWK-9 . I will also use my @WD9EWK Twitter account to send updates, and - depending on the mobile data network - pictures from where I am operating. After the road trip, I will upload my log to Logbook of the World. For those that would like to receive a QSL card for a contact with me, please e-mail me directly with the QSO details. If you're in the log, I'll get a card out to you. 73! Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK or http://twitter.com/WD9EWK

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Re: [amsat-bb] Kenwood TH-D72 SAT users
by KG5GJT 15 Dec '17

15 Dec '17

I use the Kenwood D-72 for Sats. I currently use a 2.5 to 3.5 audio cable from the radio to a digital recorder and then plug a set of Sony headphones into the recorder. Be warned you need to follow the following procedure or the radio will "freak out". If you unplug the audio cable after radio is on it affects it as well. 1. Plug everything together 2. Power on recorder 3. Start recorder 4. Power on radio 5. Work pass 6. Power off radio 7. Power off recorder Hope that helps I am attaching a link to the audio cable I use and a picture of my set up below. Hope this helps hope to catch you on a pass! 73, Brian D. Karcher KG5GJT https://www.amazon.com/gp/aw/d/B0185X0CDI/ref=mp_s_a_1_9?ie=UTF8&qid=151335… Sent from my iPhone > On Dec 14, 2017, at 8:33 PM, amsat-bb-request(a)amsat.org wrote: > > [amsat-bb] Kenwood TH-D72 SAT users

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A suggestion for ... Emergency Comms - APRS...
by Robert Bruninga 15 Dec '17

15 Dec '17

Such a highly compressed method of satellite encoding exists called APRS. >> ... the limiting factor for using LEO satellites as an Emergency >> Response of any scale, would the short amount of time of a >> given pass and the limited number of usable passes a day... > But, us ingenious ham radio operator types perhaps have the basis > of sending compressed data which conveys a lot of information. > Packed into the bytes of telemetry messages ... > How about a predefined disaster status data stream that all shelters... Use the APRS Object for a SHELTER. Just one packet can contain the position, time and date of the report, and up to 47 bytes of useful info such as 1) head count of staff 2) head count of victims 3) electrical power 4)drinking water 5) more supplies needed 6) need critical assistance. > Conversely, if multiple LEO satellites support a disaster-status protocol.. They do. APRS is currently on 3 sateliltes... PSAT, ISS and PCSAT and soon to be QIKCOM2 and PSAT2 and BRICSAT2... And TJHS hicghschool cubesat, etc > We'd need future cubesat missions capable of supporting a disaster telemetry stream. We have it. See the SATT4 single card APRS transponder. We invite every school or university that is contemplating a CUBESAT to consider using this transponder for their command and control which also provides the APRS transponder as well. Cost is under $300 or so. See http://aprs.org/satt4.html Bob, WB4aPR

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Re: [amsat-bb] A suggestion for Experimenter's Wednesdays on (PSAT?)
by Robert Bruninga 15 Dec '17

15 Dec '17

An Experiment I would like to see done is experimental DATA and RTTY modes on PSAT's PSK31 Linear transponder. I rarely hear anyone using PSK31 and so it is quite available. It has a linear receiver for any modulation going up on 28.120 MHz and then the demodulated audio comes down on FM on UHF 435.350 MHz. But the uplink is SHARED with terrestrial RTTY and DATA modes (though very rarely are there signals there)... The only catch is that there does need to be at least one PSK31 signal in the passband to cause the transponder to come up. But once up, it is a clean bent pipe for all the rest of the 3 KHz bandwidth. I read Part 97.307(f)4 and 309(a) as saying any digital mode that is less than 1 Khz FSK or under 1200 baud symbol rate can be used? One other catch. (my fault)... It Recycles every 20 seconds. Which means the carrier will drop for a few seconds as the processor is reset and then it waits for the 31 Hz detect to come up again. So time your exchanges in the 20 second repeating windows... Bob -----Original Message----- From: AMSAT-BB [ On Behalf Of E.Mike McCardel Subject: Re: [amsat-bb] A suggestion for Experimenter's Wednesdays on AO-91 It seems to me that the limiting factor for using LEO satellites as an Emergency Response of any scale, would the short amount of time of a given pass and the limited number of usable passes a day over an area needing the response. I’m not sure experimentation would find ways around this limitation. But of course experimentation is just that. Perhaps we need to get out of the box for how Experimenter’s Wednesdays work. What modes can we adapt? Can we incorporate an educational initiative, similar to ISS school contacts? Remote control APRS messaging as Mark Spencer demonstrated with MAREA? I know these seem like we are limiting contacts to just a few people, but they can reach hundreds of students and introduce satellite and radio enthusiasm to another generation of school children and millennial. 73 EMike EMike McCardel, AA8EM Rotating Editor AMSAT News Service Sent from my iPhone > On Dec 15, 2017, at 1:26 AM, Mac A. Cody <maccody(a)att.net> wrote: > I'm embarrassed to say that I've never done anything personally with > NBEMS. What I knowabout it isfrom a presentation at my radio club. > We have had a group that was experimenting with NBEMS on the club > repeater. Don't know whether they are still doing it, though. They > weren't using any special interface between radios and computers - > speaker output to microphone input in both directions. I'd like to > try NBEMS on the FM birds simply as a way of experimenting with using LEO > birds for emergency response. > > As you mentioned, there is a lot of sites out there describing how to > use NBEMS using Fldigi/Flmsg. I have not seen anything specific, yet, > regarding to using NBEMS over a satellite. I'm sure that there are > attendant challenges and opportunities doing so. > Doppler shift and signal quality will be the main challenges. MT65 > appears to be the modulation scheme of choice. Full duplex operation > would be helpful, as you could monitor your own signal to verify its > quality and how well the message got through. > > I'll have to investigate further. > > Mac Cody - AE5PH > >> On 12/14/2017 11:38 PM, Scott wrote: >> I've always been curious about NBEMS as well, Mac. >> >> There is a fair amount of info on the subject online, but could you point >> me to any particular orientation how-to that might be geared to someone >> using it in a more informal setting such as how we might use it via an FM >> satellite? >> >> -Scott, K4KDR ======================== >> -----Original Message----- From: Patrick STODDARD (WD9EWK/VA7EWK) >> Sent: Friday, December 15, 2017 12:29 AM >> Subject: Re: [amsat-bb] Experimenter's Wednesdays on >> AO-91 >> >> Now that's a good idea. Otherwise, Wednesdays on AO-85 could be >> called SSTV Wednesdays, if that's the extent of "Experimenter's >> Wednesdays" for that satellite. I would be inclined to try NBEMS, >> something I've never used. >> >> Patrick WD9EWK/VA7EWK >>> On Thursday, December 14, 2017, Mac A. Cody <maccody(a)att.net> wrote: >>> >>> If, as you stated, SSTV has run its course, maybe Experimenter's >>> Wednesdays on AO-85 could be changed to experiment with EMCOMM using >>> NBEMS, thereby keeping AO-91 as free as possible. Once that has run >>> its course, then move on to another experiment. That would keep >>> things fresh. I think a report on each experiment would be an >>> interesting series of articles in the AMSAT Journal. I think >>> continuous experimentation is a good thing! >>> >>> Mac Cody - AE5PH

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FUNcube Warehouse Outage
by David Johnson 15 Dec '17

15 Dec '17

Hi, Sorry if you experienced a short outage of the display pages, we were fixing up a problem with the channel MinMax values. 73 - Dave

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