{"id":49,"date":"2019-04-05T18:52:49","date_gmt":"2019-04-06T02:52:49","guid":{"rendered":"https:\/\/no1pc.org\/blog\/?p=49"},"modified":"2019-04-05T18:58:51","modified_gmt":"2019-04-06T02:58:51","slug":"the-dilemma-of-digital","status":"publish","type":"post","link":"https:\/\/no1pc.org\/blog\/2019\/04\/05\/the-dilemma-of-digital\/","title":{"rendered":"The Dilemma of Digital"},"content":{"rendered":"\n<p><strong>The Dilemma of Digital<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Spectrum Efficiency or Threat\/Risk? de Jim\nAspinwall, No1PC<\/li><\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">Preface<\/h1>\n\n\n\n<p>This is NOT a piece critiquing specific technologies \u2013 one\n\u2018better\u2019 or \u2018worse\u2019 than another \u2013 but about contributing and challenging\nfactors of working across both legacy systems and the various divergent new\nsystems, and the perceived state of ham radio\/repeaters\/spectrum \u2018climate\u2019 at\nVHF and UHF.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Introduction<\/h1>\n\n\n\n<p>I\u2019ve been involved in amateur and two-way radio systems for about 50 years.\u00a0 That\u2019s not a brag or challenge nor contest, but it speaks to a LOT of exposure to radio systems and the purposes they serve.\u00a0 I\u2019ve also been part of various repeater coordination, technical planning and problem-solving situations.  As Technical Committee chair and variously Board member for the Northern Amateur Relay Council of California, this issue has come up in the past, remains unresolved, and will no doubt come up again, but the community at-large needs to ask it to be addressed among any and all involved. No single entity can just drop an idea on the larger community and hope it goes well. <br> <br> I\u2019ve worked with many hams and professionals who have more exposure, but I don\u2019t think it\u2019s about quantity but \u2018quality\u2019 \u2013 of how much of what we\u2019ve seen, engaged in, and are often called to reconcile \u2013 that provides the perspectives and opens up the considerations we face today.<\/p>\n\n\n\n<p>Drawing attention to some of the proclaimed features and\nbenefits of amateur radio \u2013 technically and practically as basis for much of\nthis discussion\u2026<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Experimentation<\/li><li>Education<\/li><li>\u201csomething for \u2018everyone\u2019\u201d<\/li><li>\u201cself-enforcing\u201d<\/li><li>innovation<\/li><li>Public service<\/li><li>\u201cwhen all else fails\u2026\u201d<\/li><li>Resiliency<\/li><li>Reliability<\/li><li>Availability<\/li><li>Accessibility<\/li><li>Local and global scope<\/li><\/ul>\n\n\n\n<p>\u2026 interesting perspectives of common daily amateur radio use\nhave emerged in the past decade or so, and standout:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u201cthere\u2019s very little traffic on most local\nrepeaters\u201d<\/li><li>Radio-over-IP systems and applications \u2013\nEchoLink, IRLP, AllStar, DMR, D-Star, Fusion, P25\u2026<\/li><li>the proliferation of personal digital hotspots<\/li><li>work the world with an inexpensive radio,\ninstead of \u201cbig repeaters\u201d and \u201cexpensive setups\u201d<\/li><li>\u201cI\u2019m not very technical but want to enjoy the\nhobby\u2026\u201d<\/li><li>\u201cit\u2019s *just* ham radio, no need to get picky\nabout technical knowledge\u2026\u201d<\/li><li>\u201cwe need more spectrum\u2026\u201d\/\u201dwe need to better use\nspectrum\u201d\u2026 for digital, narrow-band, etc.<\/li><\/ul>\n\n\n\n<p>Participation Dynamics<\/p>\n\n\n\n<p>The points listed above may inspire any number of\nconversations about the state of at least the VHF and UHF segments of amateur\nradio.&nbsp; Any one or several of them\ncoincide or may be in conflict with any other aspect of amateur radio, or the\nwhole of it.&nbsp; <\/p>\n\n\n\n<p>That said \u2013 amateur radio has always been and always will be\na mostly \u201ctechnical hobby\u201d at some level. While amateur radio has made many\ncontributions to communications technology, we also have to draw from the fact\nof science that makes it possible.&nbsp; One\njust needs to accept that, and recognize at what levels attention to technology\ndetail is essential &#8211; which is almost all of them in the implementation phases.&nbsp; Use cases vary widely. &nbsp;Technology, not just what you want to do with\nit as a user, has impact.&nbsp; <br>\n<br>\nTechnology is at the heart of any past changes in this hobby, and will be at\nthe heart of any changes to come \u2013 by coincidence or necessity. You may not \u201cbe\ntechnical\u201d, so you need to let others be technical to facilitate what you want\nbut cannot do yourself.<\/p>\n\n\n\n<p>We don\u2019t know for sure, but can probably surmise some\nreasons for the apparent decline in conventional repeater use, which is used as\na reason to favor alternatives (digital.) I submit at least:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Cost of joining a \u201crepeater club\u201d<\/li><li>Suggestion\/\u2018requirement\u2019 of joining a \u201crepeater\nclub\u201d<\/li><li>X-particular repeater is mostly used by\nY-age\/-affinity of users<\/li><li>Those \u2018Y\u2019 users belittle or don\u2019t help new users<\/li><li>Maybe those \u2018Y\u2019 users *can\u2019t* help themselves \u2013\nthere is a lot of \u201cjunk ham science\u201d out there<\/li><li>\u201cI want to build my own repeater but cannot\n\u2018find\u2019 or no one will \u2018give\u2019 me a pair\u201d<\/li><li>\u201cThe site I want to put my repeater on won\u2019t\nallow the equipment I have on their property\u201d<\/li><li>\u201cThe site I want to put my repeater on would\nmake me pay rent and have insurance\u201d<\/li><li>\u201cI\u2019m not technical, I just want to talk on the\nradio\u201d<\/li><li>Former analog or new system owners transition to\ndigital because:<ul><li>Digital is \u2018cooler\u2019<\/li><\/ul><ul><li>The virtue of \u201cspectrum efficiency\u201d<\/li><\/ul><ul><li>More capable\/less complex (?)<\/li><\/ul><\/li><li>Many new users gravitate first to some variant\nof:<ul><li>DMR\/D-Star\/Fusion \u201dwork the world\u201d<\/li><\/ul><ul><li>personal hotspots<\/li><\/ul><ul><li>digital is \u2018cooler\u2019\/the future<\/li><\/ul><\/li><li>Cell phones<\/li><li>Life changes<ul><li>Active during pre-family, less active with\nfamily, renewed activity as family grows up<\/li><\/ul><ul><li>Work, retirement, RV-ing, travel<\/li><\/ul><\/li><\/ul>\n\n\n\n<p>Technical aspects are involved in at least half of the\nabove.&nbsp; We\u2019ve otherwise always been free\nand able to choose and provide for \u201cspecial interests\u201d be they technical or\non-air operations of purpose or topic. &nbsp;If\nwe don\u2019t find something to our liking we might try to grow our own affinity\ngroup\/system.<br>\n<br>\nThe dues\/cost aspects of joining a \u201crepeater club\u201d and participating is\nbasically no different for a non-repeater ham club. Members get the benefit of\nassets\/activities of the club \u2013 Field Day, special DX stations, club picnic,\nthe ARES van, training, for fair contribution to any costs.&nbsp; Yes there are extremes of\nclosed\/private\/dedicated repeaters, as well as \u2018open\u2019 systems with no specific\ndirection where you may or may not find conversations to your liking.&nbsp;&nbsp; Remember these as we move along here.<\/p>\n\n\n\n<p>Cause and Effect<\/p>\n\n\n\n<p>Whatever the cumulative sum of the above items looks like \u2013\nwhether \u2018DMR\u2019 or other took or distracted traffic\/use from most legacy\/analog\nsystems for whatever reasons or the foibles of various analog systems drove\npeople to \u2018DMR\u2019 or other digital systems, there have been and are some not\ninsignificant effects:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Digital modes do not provide any \u2018visibility\u2019\ninto various on-air characteristics \u2013 whether they be inbound noise or legit\nsignals to the digital repeater receiver or other users the digital repeater\u2019s\ntransmitter affects \u2013 there is no \u201copen the squelch to hear what\u2019s out there\u201d \u2013\nthis is where technical on-air experience is essential vs \u201cbuy a box, unwrap,\nplug-in, tah-dah!\u201d<\/li><li>As many digital system implementers may not have\nbeen able to identify and coordinate and cooperate with existing local systems,\nthey are not \u2018registered\u2019 with or otherwise publicly known through \u2018normal\u2019\nrepeater-listing resources.&nbsp; <\/li><li>Users may be quite unfamiliar with the other\nuses\/applications and spectrum reservations for weak signal, satellite, ATV,\npacket, etc. thus \u2018many\u2019 hotspots, though many are just 10-100mW with small\nlocal antennas, some do leverage higher power and external antennas \u2013 resulting\nin unknown\/undisciplined RF presence issues<\/li><li>Various digital systems making up \u2018innovative\u2019\nrepeater pairs amid existing band plans:<ul><li>\u2018cramming\u2019 between known analog channels and\ncompromising the necessary guard-band between \u2018channels\u2019, <\/li><\/ul><ul><li>occupying simplex and\/or packet channels, <\/li><\/ul><ul><li>operating in allocated experimental, satellite\nand weak-signal \u2018space\u2019<\/li><\/ul><\/li><\/ul>\n\n\n\n<p>Both the \u201cParticipation Dynamics\u201d and the above \u2018behaviors\u2019 leave\nus with various potential negative effects. Without the discipline of\n\u2018coordination\u2019 and consistent registration of various \u2018garage\u2019 and \u2018hotspot\u2019\nrepeaters&nbsp; we have VERY little idea how\nmany systems actually exist, their potential impact, and thus the claim of\n\u201cspectrum efficiency\u201d cannot be specifically found much less realized\u2026<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Likely there is more RF \u2018consumption\u2019 than\nless\/better<\/li><li>If the new user\/implementer base is unfamiliar\nwith, or deliberately chooses to ignore existing \u201crepeater coordination\u201d\ndisciplines, interference is more likely, and worse, potentially FCC violation\nfor not monitoring before transmitting<\/li><li>Whatever spectrum is being used is random,\nunpredictable, unreliable<\/li><li>It can be challenging to locate and identify the\nvarious sources of real\/potential interference, especially with hotspots that\ncome on- and off-line or are mobile<\/li><\/ul>\n\n\n\n<p>Many ambiguous and troubling things come from this:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>The apparent lack of use of legacy analog\nsystems may be a false negative signal that:<ul><li>Ham radio is dying<\/li><\/ul><ul><li>We aren\u2019t \u2018adequately\u2019 using the spectrum we\nhave<\/li><\/ul><ul><li>Worse, we don\u2019t need the spectrum we have (which\ngives some false \u2018hope\u2019 to DoD, PAVE-PAWS, etc.)<\/li><\/ul><\/li><li>The lack of awareness of how many and what types\nof digital systems are either intruding on established analog system space, or\nrandomly occupying \u2018experimental\u2019 or link or other space (e.g. 420-430,\n430-440) may similar leave the same negative perceptions above<\/li><\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">A Cautionary Tale<\/h1>\n\n\n\n<p>In 2013-2014 the conditions of \u2018digital\u2019 interests imposed\nthemselves by hijacking agreed-upon simplex frequencies, some packet\nfrequencies, and imposing mid-\u2018channel\u2019 splits producing and subject to\nguard-band spillover reached a near-fever-pitch in Northern California.&nbsp; There was a cry\/demand for the coordination\nbody to re-farm VHF and UHF to create more pairs for digital interests, or\nperhaps kick less-active analog systems off-the-air so \u2018better\u2019 digital systems\ncould exist.<\/p>\n\n\n\n<p>Amid that cry were some crazy and some very casual unrefined\n\u2018plans\u2019 to accommodate channel\/frequency shifting:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>radios with synthesizers could \u201csimply be re-programmed\u201d,\n<em>EXCEPT<\/em> that not all of them were\ncapable of the various frequency shift increments that would be required;<\/li><li>for repeaters with crystals you could \u201cjust\ntweak it up or down a kilohertz or two as needed\u201d<\/li><li>most of the \u201cdigital folks\u201d didn\u2019t understand\nthe basic concepts of guard-band and interference mitigation as they\u2019ve \u201cnever\nheard interference on their digital radios\u201d \u2013 of COURSE NOT\u2026 interference\ndoesn\u2019t pass through the digital decoders, etc.<\/li><\/ul>\n\n\n\n<p>None of that accounted for figuring out which way any one of\nthe 100+ repeaters would move up or down, and when, to make room for the new\nchannels.&nbsp; Such a logistics and technical\nnightmare had only \u2018recently\u2019\/previously been done moving Southern California\naway from 25 KHz to 20 KHz spacing at UHF.&nbsp;\nWhat had been hoped to take only a year took more than 3 painful years\nfor their community.<\/p>\n\n\n\n<p>NONE of that accounted for the fact that probably 99% of the\nradios in use by the 70,000 hams in California, 40,000 in NorCal, nor any of\nthe hundreds (thousands?) of visitors to California would ever be able to be\nprogrammed for many\/any of the \u201cnew frequencies\u201d that might be \u2018created\u2019 in\nsuch a desperate, radical scheme.<\/p>\n\n\n\n<p>Ultimately, countless repeater systems might have to be\nrebuilt or replaced.&nbsp; Countless user\nradios would have to be replaced \u2013 with, if and ONLY if enough ham gear\nmanufacturers had suitable replacement models to purchase.&nbsp; Since many of us have more than one VHF\nand\/or UHF radio \u2013 let\u2019s just guess that we\u2019re talking about at LEAST 80,000\nmobile rigs at $200-400 each would have to be acquired over some 1-3 year\nperiod of time. That\u2019s $16M-32M of new ham gear.&nbsp; Who knows if Alinco, Icom, Kenwood and\/or\nYaesu separately or combined could meet that production level.<\/p>\n\n\n\n<p>Rather than living up to a mantra of \u201cspectrum efficient\u201d,\nthey over-stepped into being spectrum ignorant and arrogant. When presented\nwith the fact and reality of spectrum management, they claimed it was being\nmade too complicated, difficult and not timely enough to satisfy them.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Conserving, or Mis-using Spectrum?<\/h1>\n\n\n\n<p>Before we can even begin to have a conversation about\nspectrum, much less prescribe a solution to wasting it, we need to understand\nwhat spectrum is and how radios present themselves within it, how it is \u2018used\u2019\nor consumed, and why.<\/p>\n\n\n\n<p>MOST of amateur radio voice operation is what is considered\n\u201cwide-band\u201d \u2013 typically at or under +\/- 5KHz spectrum use centered around a\ncarrier frequency \u2013 from the lowest end of \u2018HF\u2019 to the highest reaches\nmicrowave allocations. &nbsp;<br>\n<br>\nThe \u2018spectrum\u2019 we occupy when transmitting voice is recommended, realized, and\nadopted for the most audible, \u2018readable\u2019\/understandable aspects of the human\nvoice \u2013 as was realized by \u201cthe phone company\u201d many decades ago.&nbsp; No need to design and build phone lines for\nthe entire range of human hearing (~20 Hz to ~20 KHz) when most voice\nattributes occupy only from roughly 200-300 Hz up to 2-3 KHz.&nbsp; <br>\n<br>\nThus +\/- 5 Khz is\/was a \u201cgood number\u201d for AM and FM communications, while many\nof us may filter what we receive using SSB to 2.4 KHz, even down to 1.8 KHz if\nthere is too much high-frequency noise or adjacent signals.&nbsp; A variety of FSK and AFSK and digital over HF\nuse similar or less spectrum.<\/p>\n\n\n\n<p>Commercial two-way FM (Part 90 and specific Part 95\nservices) started out using \u2018old\u2019 wide-band of +\/- 15KHz, which sounded really\ngood, but as use increased and technology improved, there was a shift to what\nwas then called narrow-band, is now the new wide-band in the presence of +\/-\n2.5 KHz \u201cnew narrow-band.\u201d&nbsp; Seems\neverything can be re-defined if it feels better to do so.<br>\n<br>\nBand-plans\/spectrum use were built around +\/-5 Khz transmitted signal bandwidth\nPLUS some protective guard-band\/signal-edge margin to account for sideband\nnoise, frequency control tolerances, etc. \u2013 so +\/- 5KHz stations, 10 KHz of\nspectrum use\/occupation, resulted in spacing of 15 KHz between channels\/uses to\nmitigate noise and interference impacting others.<\/p>\n\n\n\n<p>The same considerations exist for \u201cnew narrow-band\u201d &#8211; +\/-\n2.5 KHz or 5 KHz of transmitted signal bandwidth or occupied spectrum is given\nsome guard-band\/edge protection resulting in channel spacings of either 6.25\nKHz or 7.5 KHz depending on the revised band-use planning.<\/p>\n\n\n\n<p>Along with the occupied bandwidth, of course we have to\nensure that transmitters and receivers stay on and within their assigned\nchannels \u2013 so there are prescribed frequency stability factors.&nbsp; For \u2018wide-band\u2019 base stations had to maintain\nstability of 2.5 parts-per-million (ppm) while mobiles and portables only 5\nppm.&nbsp; With the new narrow-band EVERY\nradio must maintain 2.5 ppm stability.<\/p>\n\n\n\n<p>Very real technical factors, stringent implements, exist to\nprotect all users from themselves and each other, lest chaos ensue \u2013 and it\u2019s\nusually the existing analog users who would suffer because they don\u2019t have the\n\u2018benefit\u2019 of digital processing masking the very real world characteristics of\nRF problems.<\/p>\n\n\n\n<p>Much of this is covered in prior paper\/presentations:<\/p>\n\n\n\n<p><a href=\"http:\/\/no1pc.org\/NARCC\/NARCCTechnicalCommittee-02-2014.pdf\">http:\/\/no1pc.org\/NARCC\/NARCCTechnicalCommittee-02-2014.pdf<\/a><\/p>\n\n\n\n<p><a href=\"http:\/\/no1pc.org\/NARCC\/NARCCTechnicalCommittee-04-2013-27.pdf\">http:\/\/no1pc.org\/NARCC\/NARCCTechnicalCommittee-04-2013-27.pdf<\/a><\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Critical Factors<\/h1>\n\n\n\n<p>For decades we have been able to present, leverage, utilize\nand prove ourselves as having some worth\/value to the hobby, the public service,\nto served agencies, because we could and did build very resilient,\nhigh-performing, ubiquitous analog FM voice \u2018systems\u2019 and methods \u2013 both simplex\nand repeaters.<\/p>\n\n\n\n<p>Our equipment, be it crystal or synthesizer \u2018controlled\u2019,\nuser radios or repeater systems, were built and implemented following known\nbest practices of commercial and public safety systems.&nbsp; Band plans, simplex allocations and repeater\npairs mostly well-known, ubiquitous.&nbsp;\nJust like commercial and public safety systems \u2013 because that\u2019s mostly where\nVHF and UHF analog FM systems came from.&nbsp;\nChances are 99.99% of hams could go from one end of the country to the\nother and communicate with most\/all others reliably.<\/p>\n\n\n\n<p>Where we installed or preferred to install significant\nrepeater, relay and remote base systems are resilient commercial radio sites\nwith stringent quality, reliability and safety standards.&nbsp; Most of these sites have some level of\nback-up power system and significant interference-mitigation requirements.&nbsp; If we expanded such systems to other\nsites\/regions to increase coverage and flexibility, we did so solely with RF\nlinks working from the same foundation as the primary system.&nbsp; We seldom had access to much less relied on 3<sup>rd<\/sup>-party\ninfrastructure resources (\u201cthe Interwebs\u201d for example.)<br>\n<br>\nWe have recently added secondary \u2018expansion\u2019 and access schemes such as EchoLink,\nIRLP and AllStar, but the core of the system was self-contained and controlled\nRF.<\/p>\n\n\n\n<p>The core of the systems were\/are also based on known,\nrecognized, accepted technical standards and coordination as far as frequency\/channel\nallocations, bandwidth, deviation, access tones, and these were either readily\nassumed and\/or openly coordinated and published for most everyone to know\nabout.<\/p>\n\n\n\n<p>We mimicked and expanded upon known good reliable common\ncommercial and public safety standards that \u2018everyone\u2019 can or could know.&nbsp; Who back in 70s and 80s not find and freely\nuse a 34\/76, 34\/94, 16\/76, 46\/88, or 28\/88 repeater system almost anywhere in\nthe U.S., plus\/minus a \u201cwhistle-up\u201d single-tone activation \u2018code\u2019, easily\nfacilitated multi-PL tone encoder, etc. ??&nbsp;\nYeah \u2013 those days are well behind us, but still\u2026 repeater directories,\nthe Interwebs, and synthesized radios expanded accessibility to the Nth\ndegree.&nbsp; <br>\n<br>\nAs all this evolved and grew, generic band-plans, repeater pairs, and other\nmostly-known accessibility evolved further. Repeater pairs were mostly\nstandardized.&nbsp; Single-tone access went\naway in deference to sub-audible\/PL, and all radios today support just about\nany known, reasonable frequency and access imaginable.<br>\n<br>\nTo some extent we can anticipate and readily adapt to the various \u2018standards\u2019\nof band-planning and repeater pairs, but better and perhaps only if we all \u2018get\u2019\nhow spectrum awareness is available and utilization can be known. As well, no matter\nhow \u2018cool\u2019 or \u201cno advanced knowledge required\u201d might be projected, advanced\nknowledge IS ALWAYS required for things to work properly, reliably, consistently.&nbsp; Hiding real-world science behind a fancy\nweb-interface or \u2018app\u2019 GUI does not mean serious properties at RF levels no\nlonger exist.<\/p>\n\n\n\n<p>A strength of conventional \u201cold world\u201d analog is that it\nnever or rarely depends on 2<sup>nd<\/sup>, 3<sup>rd<\/sup>, 4<sup>th<\/sup> party\ninfrastructure, service or access beyond our control.&nbsp; The converse, weakness, error-prone condition\nof digital \u2018appliances\u2019 is that you can easily be fooled and deprived of\ncritical situation awareness \u2013 both system-wise and beyond. But there is still\nmore equally essential characteristics to how \u2018digital\u2019 radio tries to\ninterject and impose itself on an otherwise ubiquitous well-known user-world.<\/p>\n\n\n\n<p>The fact that the \u2018advantages\u2019 of digital systems frequently\ndepend on the very infrastructure amateur radio is relied upon to displace\/backfill\nwhen it fails, undermine digital\u2019s effectiveness and potential benefits.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Similar but Different Constructs, Benefits, Risks<\/h1>\n\n\n\n<p>At a high-level there is generally no difference in the\ncomplexity, range, equipment, cost, responsibility (technical and otherwise)\nbetween a reliable quality, good coverage analog repeater and a digital\none.&nbsp; A typical construct consists of:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Repeater \u2013 analog may be $200-2000, digital may\nbe $500-3000<\/li><li>Controller \u2013 analog may be $150-1000 depending\non complexity, digital it\u2019s part of the repeater<\/li><li>Duplexer &#8211; $500-2000 \u2013 both types need some RF\nfiltering at some level<\/li><li>Feedline &#8211; $500-2000 if you don\u2019t cheap-out on\naluminum-wrapped noise coax<\/li><li>Antenna &#8211; $500-1000 if you don\u2019t cheap-out on\nsome $100 thing you\u2019ll replace annually<\/li><li>Ground\/protective fittings (PolyPhaser, etc.) &#8211;\n$60-100 per feedline<\/li><li>Power supply &#8211; $100-200 if not integrated into\nthe repeater<\/li><li>Sufficient battery backup &#8211; $200-400<\/li><\/ul>\n\n\n\n<p>The costs are variously new\/used values, depending on your\noptions for scrounging gear.&nbsp; If you\ninstall either at a non-commercial location, some cost and \u2018quality\u2019 issues may\nbe over-looked, but should not be. &nbsp;Unless you get a good-friend deal for free\nrent at a commercial site, you might pay $50-150\/month at some commercial\nlocations.&nbsp; You should ALWAYS have\nliability insurance \u2013 through the ARRL affiliated club provider or otherwise.<\/p>\n\n\n\n<p>If you determine to extend the \u2018coverage\u2019\/service of your\nanalog system you may choose the \u2018infrastructure\u2019 option of Internet-linking\n(EchoLink, IRLP, or AllStar) again over AREDN or public Internet, or a\nnon-infrastructure RF-linking.)<br>\n<br>\nIt\u2019s almost unheard of that a \u201cdigital box\u201d will be stand-alone \u2013 at least in\nthe case of DMR, and often D-Star \u2013 so you immediately have an infrastructure\nconcern \u2013 be it AREDN or commercial Internet connection.&nbsp; At that point you probably might have \u201cmore\ncoverage\u201d than a comparable analog system, or not.&nbsp; Where you don\u2019t have RF coverage someone\nmight implement their own hot-spot, which is actually not part of your repeater\nsystem.&nbsp; <br>\n<br>\nFor every system that expands coverage, there is another frequency or pair\nconsumed. This was quite evident in DMR growth in the San Francisco Bay Area,\nwith many claims of exercising \u201cbetter spectrum efficiency\u201d \u2013 yet at least 60\nnew repeaters sprang up on various hilltops and in garages, all on different\nestablished or made-up pairs with no determined frequency\/pair re-use \u2013 and\noften conflicting with known coordinated systems or causing \u2018interference\u2019 to\nthem by not heeding basic technical RF facts.&nbsp;\nBut OF COURSE digital doesn\u2019t get any interference\u2026 that users can\nactually hear behind the magic of the digital \u2018masking\u2019.<\/p>\n\n\n\n<p>Yes, a couple of digital system types are narrow-band but\nthat does not mean they can be crammed in anyplace or amid existing systems.\nImplementation of digital systems is not like buying an iPad or PC and simply\nplugging it in.<\/p>\n\n\n\n<p>Bottom-line so far is that \u2018digital\u2019 has not proven to be\nmore \u201cspectrum efficient\u201d in various ways, and in fact can prove to be more\nproblematic and overall inefficient. But wait\u2026 that\u2019s not the end of the story\nbecause this is where technology and not-technology unravel and present\nsignificant challenges to all.<\/p>\n\n\n\n<p>Other significant risk factors are apparent:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>If your \u201cwide coverage\u201d depends in the same\ninfrastructure we suggest we are better than (\u201cwhen all else fails, ham radio,\nexcept all that networked stuff\u2026\u201d) there is <em>negative\nbenefit<\/em> from the amateur radio, thus \u2018liability.\u2019<\/li><li>Analog FM is still <em>ubiquitous and deliberate<\/em> in public safety, NIFC to be specific,\nthus far easier to establish, maintain and modify communications plan\nimplementation with analog equipment than digital.<\/li><li>Analog systems typically have on-air\/over-air\ncontrol features where digital does not<\/li><li>With analog you can know if you have an\ninterference issue which provides for working around it<\/li><li>Digital system, especially hotspot implementers\nmay not be as technically skilled at implementation and remediation of the\nRF-side of the scheme \u2013 another negative benefit under critical conditions<\/li><li>Very few hams have access to or can afford\ndigital-capable test equipment to support any\/all such systems<\/li><\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">Costs \u2013 Expertise, Logistics, Time and Real\nMoney<\/h1>\n\n\n\n<p>I hear arguments both for and against doing things the way commercial\/public\nsafety experts do\u2026 <\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>One \u2018for\u2019 argument is the demand (not NEED) for\n\u2018narrow-band\u2019 and the digital technologies of which P25, \u2018Trbo\u2019\/DMR and of\ncourse NXDN come to mind, but narrow-FM is also viable. Some of this seems more\nlike virtue signaling or innovation arrogance than real benefit,<br>\n<br>\n<\/li><li>The prevailing argument \u2018against\u2019 doing what\/as\nthe commercial people do is \u201c<em>BUT we\u2019re\njust hams, the technical requirements are too strict\/difficult\/expensive.<\/em>\u201d\n\u2013 as-if they get an excuse for taking very real and necessary technical things\nthat can have significant negative impact on others too casually.<\/li><\/ul>\n\n\n\n<p>Unfortunately you cannot get the benefits of the so-called\ncommercial technologies without actually implementing them as-designed &#8211; digital\nor analog.&nbsp; The huge unappreciated\ndifferences between commercial and amateur radio practices reducing bandwidth,\nre-allocating spectrum and replacing equipment are <em>expertise and economics<\/em> \u2013 literally and figuratively.&nbsp;&nbsp; <br>\n<br>\nPlanning and scheduling who moved to which channels and when was huge challenge\nperhaps not unlike multi-dimensional chess. \u201cThe plan\u201d took years of evolution\nto consider and set deadlines \u2013 for manufacturers and users.<br>\n<br>\nObviously displacing thousands of base and mobile radios was going to be VERY\nexpensive.&nbsp; For strictly commercial\nusers, there was enough time passing that most fleets were old and\nunsupportable and due to be replaced anyway.&nbsp;\nFor public safety \u2013 our tax dollars were in play.<\/p>\n\n\n\n<p>If amateur radio is to \u2018enjoy\u2019 the benefits of\nnarrow-banding\/\u201dspectrum efficiency\u201d \u2013 a LOT of time and money needs to be\nspent \u2013 by manufacturers, users and \u201cspectrum planners\u201d \u2013 which presumably\nwould be the ARRL, about 30 \u201crepeater coordination\u201d groups, and 780,000 hams.<br>\n<br>\nBack in the 1960s when relatively few hams ventured into VHF and UHF FM\noperation, the impact and investment was also relatively little in terms of\nequipment replacement and \u201cband-planning.\u201d Maybe 10, 20 repeaters nationwide on\nonly 2-3 \u2018pairs, 200-500 radios in user\u2019s hands (or trunks!)&nbsp; <\/p>\n\n\n\n<p>Today those numbers are probably 500 times greater overall,\nand the economics of perhaps 500,000 brand-name VHF or VHF\/UHF radios @ $300\neach is a staggering amount of money of \u201cnon-compliant\u201d radios going into a\nnarrow-band concept.&nbsp;&nbsp; I\u2019d need to check\nsome numbers but it may not be too far-fetched to think that California might\nhave as many or more repeaters than most of the rest of the country combined!!!!<br>\n<br>\nFor a variety of impractical technical and cost reasons \u2013 it\u2019s essentially\nineffective to imagine much less try to impose better filtering and stability\non originally \u2018wide-band\u2019 radios \u2013 whether or not they cost $2800 or $28. <\/p>\n\n\n\n<p>Making a transition in technology ALWAYS brings cost\/\u2019complexity\u2019\n\u2013 AM to SSB, AM\/SSB to FM, FM to\u2026?<\/p>\n\n\n\n<p>Equipment aside \u2013 no two of the 20-30 \u201crepeater\ncouncil\/coordinating\u201d entities or state\/regional band and frequency\nallocation\/management schemes are the same. If they couldn\u2019t cooperate on the\nexisting \u2018legacy\u2019 plans for over 40 years, I can\u2019t imagine it will be easy\ngetting them into the same book much less the same page today.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Solutions \u2013 The Toughest \u2018Call\u2019 and HUGE\nChallenges<\/h1>\n\n\n\n<p>Change is usually hard \u2013 especially for those that would\nhave to make the changes.&nbsp; The hard part\nfor those who want changes made to accommodate them, is waiting.&nbsp; Another hard part for those who want change\nis realizing what they hoped to escape \u2013 that their technology has to work\nwithin, cooperate with, existing technologies.&nbsp;\nIn the world of RF, \u201cwe\u2019re better\u201d cannot be determined just by the configuration\non a computer screen \u2013 there is still a significant air-interface that MUST be\nregarded.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Risk\/Benefit <\/h2>\n\n\n\n<p>Anything new needs to help itself and others determine how\nto cooperatively work itself in to an existing community-at-large effort, NOT\njust impose new\/better\/shiny digital.&nbsp;\nThere is always demand for new analog systems too. &nbsp;&nbsp;Anything like this is also an opportunity to\nconsider and work with other hams across the country, some of whom have already\ninvested in \u201cnarrow-band re-farming\u201d which may or may not be a workable model\ncompatible with other regions.<\/p>\n\n\n\n<p>Would there be allocated a specific \u201cdigital segment\u201d?&nbsp; Probably not.&nbsp;\nWhy block out spectrum that might not be fully populated and deprive\nother stressed technology needs\/wants?<\/p>\n\n\n\n<p>Who\/what would be served better and how?&nbsp; We\u2019re not all going to \u201cgo digital\u201d \u2013 unless\nit\u2019s a regulatory requirement, and at that we\u2019d need to consider how to\nmitigate infrastructure dependencies and facility additional technical\nexpertise and requisite new test equipment to handle all digital methods.<\/p>\n\n\n\n<p>We have to think bigger and better about this and so far not\nenough are will to acknowledge the issues, just \u2018want\u2019 for their \u2018problem\u2019 to\nbe solved \u2013 by others, at others\u2019 expense.&nbsp;\nGiven an existing realm of ubiquitous and reliable systems, imposing\nsomething new has to help determine a better, fair, comprehensive, informed, respectful\napproach.<br>\n<br>\nWe also have to accomplish any changes without disruption to established\ncritical services may entities and served-agencies have built into their\nplanning based on the \u201cif all else fails\u201d \u2018promise\u2019.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Complete Unconditional Cooperation<\/h2>\n\n\n\n<p>Nothing can, or should change unless\/until all interests,\nexpertise and real-world conditions are openly available, realized, respected,\nconsidered and dealt with \u2013 from the realities of RF \u201cair-interface\u201d, the\nscience of RF whether analog or digital, available equipment, replacement\/conversion\ncosts, logistics and ample timing.&nbsp; Better\nif such cooperation is established at most\/all the national level and resolved\nwith few or no exceptions.<\/p>\n\n\n\n<p>First, everyone has to acknowledge and respect each other.\nSecond everyone has to acknowledge and respect the relevant science. Third,\neveryone has to acknowledge and respect and reconcile the logistics, time\nfactors and costs of change.<\/p>\n\n\n\n<p>Finally, before anything can begin, or will be accomplished,\nthe whole of all local\/state\/regional amateur radio operations in VHF and UHF\nspectrum need to be compelled or voluntarily recognize and determine a means to\nrecognize and begin the formative processes to address recent past and\nanticipated future pressures on popular spectrum, and establish a forum to work\nthrough it.&nbsp; This is long overdue but for\nthe reluctance of both sides to acknowledge each other and accept the\nsignificant challenge to resolve.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The Dilemma of Digital Spectrum Efficiency or Threat\/Risk? de Jim Aspinwall, No1PC Preface This is NOT a piece critiquing specific technologies \u2013 one \u2018better\u2019 or \u2018worse\u2019 than another [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,10,6,7,8],"tags":[],"class_list":["post-49","post","type-post","status-publish","format-standard","hentry","category-band-plans","category-coordination","category-digital","category-dmr","category-repeaters"],"_links":{"self":[{"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/posts\/49"}],"collection":[{"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/comments?post=49"}],"version-history":[{"count":2,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/posts\/49\/revisions"}],"predecessor-version":[{"id":51,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/posts\/49\/revisions\/51"}],"wp:attachment":[{"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/media?parent=49"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/categories?post=49"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/no1pc.org\/blog\/wp-json\/wp\/v2\/tags?post=49"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}