April 2019 - AMSAT-BB - mailman.amsat.org

Tutorial on Working APRS Contacts on Kenwood TM-D710
by Clayton Coleman W5PFG 15 Apr '19

15 Apr '19

Like many topics in the amateur radio world, there is a mix of what is prescribed in protocol versus how it's applied in the real world. Bob's right here. There are excess packets created by using APRS messaging vs a simple "one time" packet being sent as a UI. The weakness in using the built-in APRS functions of Kenwood, Yaesu, or other traditionally-terrestrial messaging systems is the load of 'waste' packets generated vs using a simple UI packet. The APRS messaging functions will often continue to transmit until they receive an acknowledgement. This can be problematic in a short-duration LEO satellite pass, especially when one station tries to message everyone in their HEARD list! Many people who operate solely with a radio such a Kenwood are oblivious to 'waste' packets being digipeated (repeat ACK's, REJ's, etc.) Unless you're sitting at a terminal and viewing all the packets, your view of what is passing by is extremely limited; not just by the tiny display of your radio. For fun, I suggest running a terminal attached to your radio and monitor all packets at Field Day. I've observed passes when 10-15 stations were able to exchange packets and I've observed other passes when 2-3 struggled because one or two other stations were over-beaconing and sending messages repeatedly. It's like the many new stations incorrectly assuming the best way to be digipeated is to keep pressing BCON on their Kenwood radio until the glorious "MY POS" flashes and they hear a beep! OUCH. Those are typically people on omni antennas or in their car that have no idea they've been digipeated every time but their station is not hearing. Not everyone has the luxury of sitting in their shack to operate a packet/APRS-capable satellite. At home, I use UISS. By default UISS does not request acknowledgement or require it. It will only transmit a message or position packet upon pressing the appropriate function key. This helps limit the amount of "rapid-firing" typically employed by many of the folks using transceivers with built-in packet/APRS capabilities. Occasionally I like to make contacts via ISS or other satellites with packet digipeaters using either one of my Kenwood mobile or HT transceivers. Do I use the status text method? No. I use the MSG function like others on this thread have described. I keep it short and sweet. Do you want to strictly adhere to terrestrial protocol rules for acknowledging messages, often resulting in the logjam of packets, or do you want to increase efficiency and send the minimal frames necessary to get a clean exchange via satellite with another station? I leave that up to the operator. Have fun. 73 Clayton W5PFG P.S. I think the unattended beacons remain my favorite nit-pick of packet/APRS satellites' use. :-)

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Roving DM58
by Bob Keating 15 Apr '19

15 Apr '19

Greetings All, I’m going mountain biking this morning. Should be back in time to work the 18:50 UTC pass of AO-91 and 19:00 pass of SO-50 from DM58. Not sure if I’ll make the 1747 pass of AO-92. Hope to hear you. Will be working as N6REK/7. 73, Bob. Sent from my iPhone

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JY1-sat dashboard
by Kevin 15 Apr '19

15 Apr '19

Hi All, Is anyone else noticing any issues with the JY1-sat dashboard? I can start it with the sat present and it will instantly lock and track, next pass it will ignore the signal, kill it and restart it and bam instant lock. 73 Kevin WA7FWF

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(no subject)
by Frank Staffa Jr. 15 Apr '19

15 Apr '19

Greetings everyone. Question.....Since the LVB interface isn't available anylonger, what is everyone using for a computer interface to move their rotators to automatically follow the sats? I have a Yaesu g-5500 Alt/Az and im getting tired of manually nudging it every 15 seconds or so.Thanks and 73 Sent from Yahoo Mail on Android

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First Ever L-Band QSO
by Les Rayburn 14 Apr '19

14 Apr '19

Thanks to Kevin, KK4YEL in EL98 for my first-ever L-Band QSO tonight through AO-92. The loop Yagi seemed to work well, as my downlink was loud into the satellite. Experienced deep fades as the satellite tumbled. Limited by the fixed polarization of my mounted 2 Meter Arrow antenna. Gotta think about a circularly polarized 2 Meter antenna for the attic. Big fun! 73, Les Rayburn, N1LF Maylene, AL EM63nf AMSAT #38965, ARRL Life Member, CVHS Life Member, SVHF Member

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WD9EWK road trip in southeastern Arizona on 3-4 May 2019
by Patrick STODDARD (WD9EWK/VA7EWK) 14 Apr '19

14 Apr '19

Hi! I previously posted that I will be at the hamfest in Sierra Vista AZ on 4 May 2019: https://amsat.org/pipermail/amsat-bb/2019-April/072609.html On the day before the hamfest (Friday, 3 May 2019), I will have time to visit one - or maybe both of the rarely-heard grid boundaries in that part of Arizona: 1. DM51/DM52 line, south of Willcox AZ near US-191 in Cochise County AZ 2. DM52/DM53 line, northwest of Safford AZ along US-70 in Graham County AZ Adding in the afternoon/evening following the hamfest, I might be able to make a stop in one of those places, if I'm not able to visit both before the hamfest. I have been to both of these locations in the past few months; I visited DM51/DM52 a couple of weekends ago, and was at DM52/DM53 in late December 2018. It always seems like someone is looking for these grids, whenever I visit this part of Arizona. If you have a preference on where I could stop during this road trip, please e-mail me directly. There is a possibility that between the Friday (3 May) and the Saturday afternoon (4 May) after the hamfest I could visit both of these boundaries. I will try to post an update to this list when I settle on my drive on 3 May, as well as post updates on my @WD9EWK Twitter feed. My travels that weekend should be visible on APRS as WD9EWK-9: http://aprs.fi/WD9EWK-9 Thanks, and 73! Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK or http://twitter.com/WD9EWK

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50 Students of Rajkot India enjoyed SSTV Live Demo during Visible pass of ISS
by Rajesh Vagadia - VU2EXP 14 Apr '19

14 Apr '19

To spread awareness of Amateur Radio, Satellites & ARISS activities in the region we conducted interesting event recently. On 12th April 2019 we openly invited students & citizen of Rajkot - Gujarat to be present & witness SSTV Live Demonstration, that too during Visible pass of ISS from terrace of my home. More than 50 students & citizens assembled to my QTH by 18:30 IST (13:00z). We gave printed ISS tracking chart/ISS crew details to all of them, and explained how to use chart. Myself Rajesh Vagadia VU2EXP gave brief talk on Amateur Radio, ISS, OSCAR Satellites, Life of Astronauts, ARISS SSTV event, Student Outreach Program etc for one hour. Small display of radio stuff were also kept. Everybody get excited to learn such new things (for them) happening in Ham Radio world. Good Visible ISS Pass of -3.0 magnitude with elevation of 36° was targeted for Live Demo, calculated for my Grid ML52jh. With my 3 ele Yagi, VHF HT & recording device we started to track ISS at 19:27 IST (13:57z). Within a minute ISS started to appear from NNW direction moving towards SE. Students were requested to control their excitement & to keep silence as we were also recording audio. Soon sstv signal also get heard on 145.800 MHz. SSTV signal for two images were received & recorded. It was exciting experience for all to sighting ISS at the same time getting signals from it, felt like having handshake with ISS crew! After pass, we amplified weak audio in Audacity & decoded two images (though bit noisy) with MMSSTV. Decoded Images were shared with all students as souvenir. It proved great learning experience for all. Had lots of Q&A till late and enjoyed light refreshments at end of the program. As everything was arranged at our home I need to thanks my XYL Kiran, harmonic Snehal VU3WHO, brother Prakash VU3PLJ & nephew Priyesh VU3GLY for extending helping hands. Btw, leading newspaper Divyabhakshar supported this radio experiment & published good articles (though in regional language Gujarati), pse find it's link below. http://tinyurl.com/iss-sstv-demo-news I am thankful to all hams and members of ARISS, AMSAT, ISS Crew, Space agencies, SSTV Award Manager etc involved in such a wonderful educational event offered to the world! Thanks & 73's Rajesh P Vagadia VU2EXP Rajkot - Gujarat (India) Regional Coordinator West India Zone AMSAT-INDIA M: 9898283916 E: vu2exp(a)gmail.com www.qrz.com/db/vu2exp

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Tutorial on Working APRS Contacts on Kenwood TM-D710
by Les Rayburn 14 Apr '19

14 Apr '19

Searching YouTube and Google without a lot of success. I’ve found videos on how to set up the TM-D710 for APRS QSO’s, but nothing that demonstrates the actual steps involved in completing a contact. Should I “beacon” a message that says “CQ DE N1LF EM63 K”? How will I know if I’m getting a response? Do I then transmit pre-programmed user messages? How do I enter the other stations call sign on the fly? How do I switch to the next message? I really need a “for dummies” guide on this…and can’t seem to find it. Can anyone point me towards an article or YouTube video? 73, Les Rayburn, N1LF Maylene, AL EM63nf AMSAT #38965, ARRL Life Member, CVHS Life Member, SVHF Member

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ISS SSTV weekend
by Tom Schuessler 14 Apr '19

14 Apr '19

Quoting the news release promoting the transmissions this weekend. “This event uses a computer in the ISS Russian Segment, which stores images that are then transmitted to Earth using the ARISS amateur radio station located in the Service Module which employs the Kenwood TM D710E transceiver.” Well while trying fruitlessly this morning to decode cleanly, the images from the ISS, I heard the collective scream of hams all over the world, “TURN THAT COMPUTER SOUND CARD OUTPUT VOLUME UP PLEASE!” Next time. Tom, N5HYP

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Operators Active on AO-92 Mode L and APRS ISS/NO-84
by Les Rayburn 14 Apr '19

14 Apr '19

I’m trying to compile a good database of operators who are active on AO-92 Mode L (1.2 Ghz). Also interested in compiling a list of operators who are active in having digital APRS QSO’s through ISS, NO-84, or AISAT-1. Note: I’m looking to hear from operators who are active, not just equipped to work these modes. Once the results are in, I’ll share with anyone interested. You can e-mail me directly at: les(a)highnoonfilm.com so we don’t hog bandwidth from the e-mail list. Thanks. 73, Les Rayburn, N1LF Maylene, AL EM63nf AMSAT #38965, ARRL Life Member, CVHS Life Member, SVHF Member

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