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GET /hyperkitty/api/list/[email protected]/email/2Y56W5HCRMTPQ6ZWD3ZVUJ2PJUOPDSN3/?format=api
{ "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/2Y56W5HCRMTPQ6ZWD3ZVUJ2PJUOPDSN3/?format=api", "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/?format=api", "message_id": "[email protected]", "message_id_hash": "2Y56W5HCRMTPQ6ZWD3ZVUJ2PJUOPDSN3", "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/JQ6BU22IYP4PVZI5X4MCII4USJY7ENAU/?format=api", "sender": { "address": "bryan (a) kl7cn.net", "mailman_id": "4060a44f8976432582122ef012353229", "emails": "https://mailman.amsat.org/hyperkitty/api/sender/4060a44f8976432582122ef012353229/emails/?format=api" }, "sender_name": "Bryan KL7CN", "subject": "Re: [amsat-bb] ANS 321 AMSAT NEWS SERVICE SPECIAL BULLETIN - AO-85\tCommissioned, Handed Over To AMSAT-NA Operations", "date": "2015-11-18T23:48:03Z", "parent": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/GIEI3XF76W4USTYCMFG3OEWZUPJSFOQC/?format=api", "children": [], "votes": { "likes": 0, "dislikes": 0, "status": "neutral" }, "content": "Phil, I don't dispute your expertise in this opinion -- you're right when you say:\n\n> It's past time for AMSAT to move into the all-digital era.\n\nBut, the appeal of using a pair of HTs or other simple radios with an Arrow sure is strong -- especially for truly neophyte operators.\n\nWhat would replace this entry level equipment? A laptop and an Arduino and a radio?\n\nReally curious what you think; I expect you have a very learned opinion.\n\n-- bag\n\nBryan KL7CN/W6\n\nOn Nov 18, 2015, at 15:28, Phil Karn <[email protected]> wrote:\n\n\n> AMSAT NEWS SERVICE SPECIAL BULLETIN\n> ANS-321\n\n> Downlink audio is 5 kHz deviation, as expected. Many will perceive\n> that the audio is \"low.\" This is an effect of the filtering below 300\n> Hz, which provides for the DUV telemetry, coupled with any noise on\n> the uplink signal resulting from lack of full quieting or being off\n> frequency. That makes for less fidelity than a typical receiver in\n> terms of audio frequencies passed.\n[...]\n\n> It is important to remember that science is the reason behind the\n> Fox-1 satellites. Not only does science help with the launch cost, it\n> provides a great amount of educational value both from the science\n> payload and in amateur radio itself. The data-under-voice (DUV)\n> telemetry is an excellent way to provide the science without\n> sacrificing the use of the satellite for communications, which would\n> be the case if higher speed downlinks were needed. DUV provides\n> constant science as long as the repeater is in use, which in turn\n> provides more downlink data for the science - a mutually beneficial\n> combination.\n\nI designed the DUV telemetry system on Fox-1, with an important\nsuggestion (use 8b10b coding for spectral shaping) from Tony, AA2TX.\nIt's important to remember the severe design compromises imposed by the\nrequirement that the satellite itself be an analog FM repeater,\nconfining the telemetry to modulating frequencies below 300 Hz.\n\nThese design compromises would have been unnecessary with a fully\ndigital communications payload, like those on every non-amateur\nsatellite launched in at least the past decade or two. I've made it\nclear that this is my last telemetry design for an analog spacecraft.\nIt's past time for AMSAT to move into the all-digital era.\n\n--Phil, KA9Q\n_______________________________________________\nSent via [email protected]. AMSAT-NA makes this open forum available\nto all interested persons worldwide without requiring membership. Opinions expressed\nare solely those of the author, and do not reflect the official views of AMSAT-NA.\nNot an AMSAT-NA member? Join now to support the amateur satellite program!\nSubscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb\n\n", "attachments": [] }